Sustainable Roofing Technologies Column

When are green roofs really blue?
By Ralph Velasquez, Sustainable Roofing Technologies Editor
September 14, 2008

Dear Readers,

As many of you know, I personally like the term vegetative roofs, since “green roofs” implies the roof's environmental aspect or perhaps its color, but not its primary functional element. I suppose, the illustrious editor of this website may take exception with that, it is after all, www.greenroofs.com! (Publisher's Note: That's why we call them "greenroofs" and not "green roofs" so there is no question in terms of the roof color or use of ecologically friendly materials - a greenroof means a roof with plants on it!)

That said, this month we are going to talk a bit about another “green roof,” one that is often “blue” or perhaps, one could even define them as “yellow” like the sunshine or gray, which many of them are before being coated or even color-less, for the power they generate has no color at all. All this leads me back to green, as in the color of money they can save and cost anyone who installs a solar rooftop system.

Solar roof installations are referred to as Photovoltaic (PV) systems or when incorporated into a building component like a rooftop or a wall, they are known as Building Integrated Photovoltaics (BIPV). We will focus on BIPV, since we are not interested in utility-provided PV, like those cool solar arrays you see on The Discovery Channel or like this one below at left @ Nellis Air Force Base in Nevada.

First a little background for the initiated, without getting too deep. There are several PV technologies to consider. Typically when we are discussing PV panels, whether they are on a rooftop or on the ground, the basic type and the type many people think of first is crystalline silicon based panels. This is considered first generation technology and is the oldest type of PV technology. While this has been around quite sometime, there have been many enhancements to the technology, especially in terms of efficiencies of the panels. When we see a PV panel on the roof tops it looks more like this type of application:

When we move to BIPV, we typically are talking about thin-film technology based on a variety of approaches. Considered first generation is Amorphous Silicon (a-Si) and Cadmium Telluride (CdTe); considered second generation is Copper Indium Gallium di-Selenide (CIGS) and considered third generation or emerging technologies are Dye-Sensitized (DSC), organics or nano-materials. These various materials are now being used in roofing materials, walls, windows and other building components to turn buildings into something that generates power and reduces electrical needs from the electrical grid of the country.

We will take our limited space to review rooftop applications and the use of thin-film in those applications. While Amorphous is considered first generation and is the most mature of the thin-film technologies, there have been many technical breakthroughs that have improved this product and make it a great component to go into roofing materials.

When capturing light from the sun, the better the panel is at accomplishing this, the more efficient in producing power it is, so the idea of slicing the incoming light into its various light spectrums has been introduced. The idea in these single, double or triple junction configurations is to capture various light spectrums and improve the efficiency of the panel. Simply, various layers in the cell are created to catch the light missed by the layer above it, as the color spectrum of the light beam passes through one, two or three “junctions” or “flat plates,” if you will, thereby improving the panel’s output.

What you laminate to is important and more manufacturers are moving from heavier materials like glass to stainless steel or plastic laminates. Lighter is better!

A second “first” generation technology is the CdTe guys, also around from the same time frame as amorphous - the 1970’s - and is well understood. This material has two great advantages, having great potential for high efficiencies and a very low cost for large-scale manufacturing, making it far more desirable for solar farm applications. While there is application for rooftop applications, we will not focus here much other then to mention it as a mature PV technology.

The second-generation material causing some excitement is CIGS technology. CIGs have been the darling of much Wall Street investment and media attention, as it holds promise for many applications. It has demonstrated record levels of efficiency in the lab, but as is true with all published lab results, the field capabilities are far lower then what can be accomplished in lab conditions (typically 50% of lab conditions), so be careful of what you read or hear. Someone may not be intentionally misleading you, as they may just have incomplete facts. CIGS can be attached to rigid or flexible substrates, has high efficiency and exhibits excellent stability over time. This technology is still very new and companies are just beginning to make this stuff in commercial quantities.

The emerging or third generational materials are items like DSC, which seems to have the early lead in this category, or organic materials and nano based technologies. This category has great advantages in low manufacturing costs and relatively inexpensive materials, along with simple processing. Just a bit early to know exactly where and how this will play out in the marketplace.

With those brief introductions, I want to go back to the industry's current workhorse for BIPV, especially as it relates to roofing: amorphous silicone or a-Si. One of the reasons a-SI works well for roofing applications is its ability to maintain conversion efficiency even in low and in-direct light levels. In addition to this advantage, many feel that a-Si will dominate the market for at least the next 5-10 years due to additional advantages such as unlimited feedstock sources, its light weight, roll-to-roll manufacturing processes and continuous improvements. I would think the CIGS and emerging technology folks may take exception to this but only time will tell which “truth” becomes evident.

While there are numerous advantages, there are drawbacks to any technology and a-Si or BIPV as a concept for that matter has some that need to be addressed in the industry. There are concerns around the heat build-up issue that all PV cells generate. If solar energy is not converted into usable power, then heat is thrown off, much like your computer, which if it gets too hot can get fried. Heat build-up limits efficiency and more importantly, what happens to the roof membrane if a constant heat source is applied? We know from traditional roofing technology that heat is an enemy of roof life and so we spend a lot of time and technology to reflect heat and protect the membrane from its ravages.

So what role will heat build-up from thin-film play in the life expectancy of the membrane? Then we have questions like wind uplift, fire ratings of a combined system, maintenance, mechanical damage, hail, foot traffic, wiring, inverters (the mechanical unit that converts DC power to useable AC power for most buildings), etc. I n other words the industry is on the right track but it is still very new and there is as much as we don’t know as we do know about BIPV applications.

So what is a business or homeowner to do? You want to go “solar” but which technology, which approach, which roof can I combine with a vegetative roof, who do I use to install, how do I conduct maintenance, what maintenance, what about warranty, and so on?

The usual good advice for many purchases applies here. First do your homework - there is a lot on the Internet these days. That said, just because it's there doesn’t mean it’s true. Hmmm, that means this article as well…..but I digress. Second, work with reputable people, get references, and check out their capabilities. Third, ask if they can stand behind their offering; will they be in business next year or five years from now, ten, twenty, thirty? Fourth, read the warranty closely. The fine print is fine for a reason. Know what the exclusions are, so many of us don’t. Fifth, there are various trade organizations that reputable companies belong to, so check to see where the company you are considering is a member. Finally, be cautious, even doing due diligence is not always enough in an industry that is changing rapidly. Lots of good people out there but there are always those who are less so, and you want to avoid those.

Hope our brief journey into BIPV was helpful and started you thinking about another sustainable solution, besides our favorite on this site. By the way, the blue color on most PV panels is from a coating applied to the basic silicone, which is dull gray. So go out and be green, blue, yellow………… oh heck, just be colorful!

See you next month!

Ralph heads up Tremco's program for sustainable roofing, waterproofing and building envelope solutions, including green roofs, photovoltaics (incl. BIPV), cool roofing and bio-based materials. Previously founding his company Integrated Building Technologies (IBT), Ralph has been involved in the roofing industry since 1978 with a wide range of roofing experience serving hospitals, schools, universities, industries, major corporations, non-profit organizations and property management companies.

Tremco Inc., located in Beachwood, OH, is a division of RPM (Republic Powdered Metals), providing "Roofing and Waterproofing Peace of Mind" to their customers since 1928. Tremco has long been a leader in the concept of sustainable roofing, with a historical focus in keeping "good roofs good", thereby improving the life-cycle of the roof assembly, forestalling replacement and reducing landfill burdens. Further promotion of this concept came with the advent of asbestos free materials, low and no VOC products, recycled content, cool roof technologies, Energy Star, LEED, Title 24 (CA) and now increased emphasis in vegetative roofs and Photovoltaic solutions.

As a major corporation with construction related activities around the world, Tremco is committed to providing building envelope solutions that will meet the customers need for value driven sustainable solutions. We are committed to building upon our past sustainable approaches, creating new mechanisms to achieve improved levels of sustainability and value for our customers.

It’s not easy being green!
By Ralph Velasquez, Sustainable Roofing Technologies Editor
August 13, 2008

We all recognize the famous saying from the Muppets kingpin, Kermit the frog. This has been ringing in my head a lot lately as my wife and I have been in the process of building a new sustainable home. We have found out that in Tennessee anyway, this process can be difficult.

A few years ago, we sold our home on the golf course and decided to make a serious personal commitment to a more minimalist and green life style. Now, we already had begun the process of downsizing our lifestyle years earlier and had continued this process when we moved to the golf course in 1999. By today’s standards we had a modest home, a 1,900 sq. ft. condo on the 18th hole. This had been prompted by our desire/need to move closer to our oldest daughter who was having our first grandchild. When we decided to sell this property and move downtown, this was the initial erosion process of my golf game. It wasn’t great to begin with then and today is unmentionable.

We had decided to move into downtown Nashville and get a condo in the city center. This would allow me to move my offices downtown, reduce our need to drive anywhere, making a huge carbon impact reduction on a personal scale, since we could walk most everywhere and further reduce our square footage of living space. We made that move in the spring of 2005, downsizing even more to about 1,000 sq. ft. While adjustment took a little bit of time, it wasn’t really all that long before we adjusted just fine to the small footprint and began to enjoy the city lifestyle. While I enjoyed the city and loved all the time savings, ecological and logistical advantages, I did not enjoy the high-rise style building of our condo. So after a little more than two years, our conversation turned to what else could we do to maintain a minimalist lifestyle and get back into more of a house style of living? We talked many a summer evening on our balcony overlooking the city lights about all our options and finally came to our “Eureka” moment. We would remodel or build a sustainable home in or near the city. This would be our final home; one where I could finish my working career and were we could retire. The idea seemed perfect and green!

After reaching this most critical decision, we first set out to find the perfect property in and around the city where we could rescue or remodel an existing home in a sustainable manner. Over the next several months what we found were homes that were big enough to park airplanes in, which seemed a waste given it is just my wife and I. We also found property that might have worked if we were willing to tolerate the high level of crime and pay prices that were not even close to being in line with what we were willing to pay. Seems the recession was not being felt much in Nashville last summer. So we abandoned the idea of remodeling and decided to look for empty lots and build something new. Again, we were thwarted. Not much that was empty in the city and what was had the same problem of crime or price or both. So with some reluctance we moved farther out to look for the right piece of property.

The property was critical to the design of the house since we had decided that we would push the envelope for Tennessee at least. We decided the house would be 1,000-1,200 sq, ft., with all living space having multiple functions. We would get off the electrical grid entirely, by using building integrated photovoltaics on the garage roof and battery storage. No utility company for us! And, of course, we would install a vegetative roof over most or all the house. This would allow for stormwater capture, energy efficiency, noise reduction and perhaps even a bit of food production in the manner of herbs for Lea’s kitchen.

We would re-capture the remaining stormwater and re-use for gray water needs. We would also install a compost toilet, thereby eliminating the need to tie-in to the sewer infrastructure. All building materials will be evaluated for VOC content or any other negative health related components. We will use highly renewable materials such as bamboo flooring, recycled glass and concrete countertops (with fly ash, of course). As much recycled materials as we could think of would also be incorporated into the design. We would balance the end product with the manufacturing process, trying to make the best overall sustainable decision we can for the site and our home. Finally, we would eliminate a central cooling and heating system, along with the “evil” ductwork my wife has come to loathe. Instead we would design a home that was as naturally cooled and heated as possible, then supplemented by portable room units powered by the solar system on the house. Time and space does not permit me to outline all our ideas but you get the drift of where we are headed. So what could possibly be so hard about this Shangri-La?

We are just in the early phases of design and the property has been found. We chose a 5-acre lot nestled in the woods and adjacent to a pond that will aid in the natural cooling effect needed in the hot, humid Tennessee summers. There is open space for the garage and its photovoltaic system. So what are the early challenges? Try financing!

Seems that building a house this green is a bad thing, according to most banks in middle Tennessee. Because of our credit rating? Nope, we are excellent candidates. Because of our down payment? Nope, good there. High outstanding debt? Nope, don’t have any, that minimalist lifestyle, ya know. It seems, they have several concerns.

Since we are building such a small house, we will be out of whack on the costs per sq. ft. when compared to other “comparable” houses. In fact, building healthier, more efficient homes seems to be a poor financial choice according to the financial institutions. They are worried about risk and what if they have to take back the house and re-sell it. Who would buy it they say? I say pick up a newspaper, magazine or get on the Internet and see where things are heading.

My house will be in demand in the years to come, while those monstrosities that burn high levels of energy will be the ones hard to re-sell. In fact before they are worried about re-sell, they are worried about just how to establish the value of the house to begin with and be able to determine what they will lend on this property. Perhaps they are just a worrisome bunch. They haven’t made very good decisions lately it seems. Perhaps I should re-think using a bank, they are kind of risky, ya know. He he! One ‘green” lender (that’s what their advertisement said), told me that being off the electrical grid is one of my major hurdles in getting financing, so we just might have to hook up to the grid, just to get financing. Seems like a total waste to me.

Then there are the codes. We have just begun to bump up against this process. My architect, who is well versed in what we will need to do, seems to think we will have to put in a separate septic field, even though we will never need to use it, thanks to our composting toilets. Building codes in middle Tennessee have not caught up with technology and those responsible for our public health, cannot conceive of a toilet that does not need a septic field. Well maybe I’m being a bit harsh, they might be able to conceive of such a thing, it’s just not allowed. Again more waste (I mean of money and resources, not the other), having to put in something I don’t need or want because we are behind the times in building techniques.

We have not even begun to touch the many other design considerations that will fly in the face of conventional wisdom. Never mind that is a healthier house for us or better for our environmental future or is energy efficient, it doesn’t fit and so you can’t do it. So what does this personal saga have to do with this column and our monthly topic of sustainability? I think the title says it all. It isn’t easy being green and there are many roadblocks in building a hospital, a school, an office building, a manufacturing facility with green building practices in today’s economy.

While there are many challenges, there are many reasons to persevere; changing the status quo by challenging what is, with what can be. I encourage those of you who are doing something sustainable where you live, in your homes, in your workplace, in your business, to keep up the good fight of faith. Believe in what you are doing, be willing to pay the price, as you must always do if you want to change something worth changing and don’t despair, you will see sustainability become the new norm. There are thousands of things that once were difficult for us to do and today are easy, even the norm. Things like diversity and gender equality, heart surgery, cancer treatment, airplanes, world travel, space travel and freedom. These are just but a few of those things that once were hard and now are most common.

The term sustainability is being heard a lot these days. So what is it really? How do I apply it to my roof? Is it the same as being green? What about “greenwashing?” How do I go about getting more sustainable or green, whichever word I’m suppose to use anyway?

These and many more good questions are being asked each and every day in countless offices, among many individuals and we are all awaking to a new dawning, that to be green or sustainable is challenging at best and downright impossible for many of us. Perhaps we can unravel this a bit for all of us. In my introductory column, I wrote that I had fondly remembered the founder of our company talking about “keeping good roofs good” and how this struck me as being very sustainable, many years before it was fashionable. Many of you know that reuse of old materials sometimes makes great sense or is done because of the necessity of the situation. Either way you are practicing sustainability.

If one is going to tackle the question of sustainability, the first issue on your plate is how far reaching do you want to go? Do you want to measure where the stuff was originally pulled from the earth? How it was it mined or grown? How it was transported? Manufactured? Packaged? How much energy was used in any or all of these processes? How long it lasts? Does it impact the environment during installation or its use? Longevity? How it is handled at the end of its useful life? Does it go to a landfill? Will it be recycled? How much energy does it take to recycle, more then if we produced new goods? If your head is not spinning by now, then we could delve even deeper, but I think you get the idea that there are many ways to measure sustainability, so the first step is for you to think about how far you want to go.

I would contend that any improvement in any one of these areas could be considered sustainable. Some would argue that if improvement is achieved in only one product or approach and that the overall impact is still negative, then what have we achieved? Others would say we need to account for most or all of the categories listed in the previous paragraph. So, while you may already be arguing with me in your head, please note I said, “could be” in my first sentence, not “should be” or “would be”. HA, HA, had to go back and read that again, didn’t you! I would add that any progress is better then no action, yet the danger is that "some" is way short of what we need to do to make a true impact in the built environment. It's kind of like needing to lose 30 lbs. to get healthy and you lose only 5 lbs., stop there, then talk about how you have gotten healthier by losing those 5 lbs. Well…yes and no. Yes, you are better off then having gained 5 lbs. more, but you are being a bit self-delusional if you think you are really healthy. Ouch! I wasn’t talking about you; I’m talking about the other guy.

OK, point made, now what can I do! Well, first make that all-important decision about how far you want or need to go. Second, get educated or enlist someone who is educated on the issues of roof sustainability. Third, set an agenda on the objectives you decided on earlier. Be realistic. Think diet. You didn’t gain all that weight in one day and you won’t lose that way either. Changing sustainable habits will be much the same. Don’t forget to look at what you are currently doing both in process and products; you may already be more sustainable then you think. Capture that data. Fourth, start! Sustainability is like cleaning a messy room - sometimes it looks so overwhelming and we don’t where to start, so we don’t. The secret is to start anywhere and soon, the road will become clearer as you go. Again, capture what you do and document any savings that this action brings to you, your customer or to others. Think broadly; sometimes, there are savings that go unnoticed, simply because you don’t see immediately how your actions have saved time or money. Keep evaluating how you are doing. Make course corrections as need be. When you get where you wanted to go, celebrate, then review and see if you can do more from where you currently stand.

Some practical hints on roofing. Can the roof be saved? Can the life be extended through a maintenance program? What about non-destructive testing methods to find wet insulation, while it is small and before it spreads like cancer through the roof, causing premature replacement and impacting landfills? Wet insulation does not insulate, so keeping the insulation dry saves energy. Could it be retrofitted with a vegetative roof? What about washing those white single ply roofs to make sure they are operating @ peak reflectivity. This will extend life and save energy. Think about green cleaning products and processes if you clean the roof. Can you coat the dark surface with a reflective coating? Saves energy and extends life. Make sure you properly insulate in the first place, as there are many under-insulated roofs out there. Could you use an integrated photovoltaic solution? In some states, this is cost neutral. Can you build with better quality roofs, so they last longer, thereby reducing the use of new virgin materials, lowering impact on landfills, reducing energy use for transport and production?

The list could go on but by now you’ve got it! THINK, PLAN, ACT and you will become more sustainable in all your roofing decisions. In fact, THINK, PLAN, ACT is a good formula for a lot of things in life. Just wish I could EXECUTE better then I do.

Have a great 4th!! God bless the USA!

Ralph P. Velasquez
Director, Sustainable Technologies Group
Tremco, Inc.

Now that the light-hearted introductions from last month's article have been completed, it’s time to dive into the real issues of sustainable roofing. The question is what to write about in the first article? What I have chosen for our first chat is the issue of money. Ah, money, the issue that we think more about, save one other topic, which is not appropriate for this column space or audience. OK, stop daydreaming and bring your thoughts back to the issue at hand. We were discussing money or more specifically, the issue of first costs relative to vegetative roofs (VR).

Just a few years ago, VRs were considered and then dropped from the project due to first costs, when the inevitable VE process took control. While money will always be a part of every discussion relative to the built environment, the understanding of how to evaluate a VR project is beginning to be broadened. I noticed just two years ago that when a potential client heard the installed costs, they fell off their collective chairs, regrouped, then cut out the VR from the project design and moved on. But, things are changing!

What the end user and the design professional have begun to understand, is that once the initial shock of the first costs are said out loud, the VR can be a great tool to offset numerous construction and operational costs, making a VR a very attractive, cost effective alternative. How is that possible?

First, we need to consider the issue of stormwater. Can we use the VR to offset the costs of retaining stormwater on site? If we have to reduce the amount of stormwater runoff from the site, then there may be savings from having to dedicate other valuable land space to this effort. Perhaps we can save the costs of below grade water storage. Maybe the land that would be used for stormwater capture could be put to use in income producing activities. Any costs that are mitigated, avoided or reduced from the use of VRs, need to be captured in making the business case for a VR. Those costs need to be set against the delta of a VR versus a conventional roof assembly.

Second, we need to consider the energy savings impact of a VR roof. VRs have biomass, provide shading and evapotranspiration (sweating), to reduce the amount of heat transfer and impact the energy usage of the area in question. How much depends on the VR design, roof to wall ratios, plant choices and maturity of the plants, how many floors, heating and cooling equipment, how efficient they are, whether or not air is being pulled off the roof surfaced, pulling cooler air from the VR, then a conventional roof surface. While numerous studies are in progress and final results yet to be verified, it appears that an extensive VR can produce an “R” factor of 2-10, not counting the roof insulation being used. We need to capture these costs savings in making the business case for VRs.

Next, we need to consider the life extension of the roof membrane. We know that ultra-violet is an enemy of every roof, so if we can bury it and protect it from heat, thermal expansion and contraction forces, mechanical damage such as is experienced from hail, wind, foot traffic or people working on the roof, then we can push out the life cycle of this roof. This life cycle extension can be significant enough to make the initial higher costs of the VR a mute point, often driving the annual cost of ownership below conventional roofing options. Let’s be conservative and just say it adds to the business case for choosing a VR.

Now, let’s consider some of the other benefits that help make the business case for VRs. If we install a VR and can create a public relations or marketing advantage in our particular sector, then this value must be added into the equation. Each business has a marketing cost associated with business, as they compete against others in their marketplace. If my business has better equipment or better service or a better facility and I can take advantage of this in my market space, then this has a value. I believe VRs have this unique market value for anyone that installs a VR, at least during the emerging phase of this technology. How much is that worth? If marketed correctly, it can be significant. Whatever it is, it needs to be captured and applied to the business case for a VR installation.

We can mitigate sound with a VR, so what if we can offset sound damping material in the construction? Again, that costs need to be captured in the business case model. In some applications, we can actually produce an income source from the VR. Whether we produce herbs or other edible produce, produce rentable space or can generate fees for a lawn bowling VR, as is done in Minneapolis on a bar, not to mention the additional libations sold because of this rooftop activity, there are and can be many additional offsets that need to be captured in our business case model. What of the tremendous health and productivity benefits? This can impact a business model incredibly. Just think. What if access to a VR increased productivity by ¼ of 1 percent per annum? What if there are 3,000 employees who have access to this roof, what if their average salaries were $35,000? Simple math would tell me that over $2.6 million dollars of additional productivity might be achieved. At this rate how many years before a ten million dollar VR would pay dividends? Too simple you say? You input the right numbers just input something because this could a real savings to the owner and it needs to be calculated. Oh, by the way this is close to a real life example.

Overall, there are some twenty benefits associated with VRs, some huge, others minor and specialized, but whatever the scale of the benefit, we do ourselves and our clients a disservice, if we do not capture these savings and help them make an informed decision. At the end of the day, if we capture all the costs savings available in a given project, we would find very few poor candidates for a VR installation. Not every roof can and should be fitted with a VR, but more would and should be fitted with one if we think more broadly then we currently do. This thought process does not even begin to touch the macro issues associated with air pollution reduction, heat island reduction due to city scale VR installations, savings on city-wide infrastructure investments for stormwater runoff, water quality improvements of what does runoff, aesthetical value and the list goes on. Boy, I’m just getting rolling and it’s time to stop.

I think you get the idea. To help, a tool has been developed to help you capture these costs. You can access this tool, called the GreenSave calculator provided by Green Roofs for Healthy Cities (funded by Tremco Roofing). Go to www.greenroofs.org or www.tremcoroofing.com to run this tool. It’s a version one software tool, so it has some glitches and needs additional layers of sophistication but hey, what version one software tool did you ever use that was all you wanted it to be? Two more phases are planned to improve the tool and increase its local flavor. If you don’t like it, blame me; I chaired the sub-committee that built it, along with the Athena Institute. Publisher's Note: Download the Press Release of 07.11.07 here.

Oh well, you can’t wait for everything to be perfect before you start; sometimes you just have to wade in and make the best of it. My dad always said it is easier to turn a car if it is moving, then if it is standing still. You know what? That’s not bad advice for living either. See you next month. For now, off on vacation, taking the grandkids for some good old time summer fun in WI.

Ralph P. Velasquez
Director, Sustainable Technologies Group
Tremco, Inc.

Inaugural Sustainable Roofing Technologies Column, April 2008
By Ralph Velasquez, Sustainable Roofing Technologies Editor

Many of you have come to know me as the ASTM Editor on this website for a few years now and I have enjoyed being your ASTM conduit during that time. While that has been true, I have always believed that more needed to be communicated to the market about sustainable roofing and their design. Recently, the Publisher/Editor of Greenroofs.com, Linda Velazquez (no relation) asked if I would be willing to write a more regular column about this very topic, something I have agreed to do. Perhaps Kelly Luckett, who also writes for this website, under the “Roving Exhibitor” column can continue the important task of reporting back to you on our semi-annual ASTM meetings. Kelly is also part of the committee and already writes a great column. Guess I should ask him.

So what is sustainable roof design and why write about it in this forum? Perhaps a little history will help give context. I have been in the roofing industry since 1978, having been mentored by great roofing professionals whose careers reached back into 1940’s. I even had the pleasure of meeting our company’s founder who started my current company (Tremco) back in 1928. Some of what I remember from those early days and from such experienced men, were ideas of roof life extension, durability, adaptive re-use of selected materials and other sustainable practices that are very much back in vogue today.

Based on these well tested ideas, the industry has taken on additional enhancements relative to sustainability, things such as vegetative roofs, building integrated solar membranes, bio-based roofing materials, increased recycled content, increased concepts of material re-use and so many other ideas that in years past would have been considered wacky or not economically viable. Well, the world is changing and our industry is rapidly changing with it.

Over the next several months and for who knows how long, together we will explore the many varied ideas of roof sustainability. This will include of course, vegetative roofing and many of its varied components and concepts. We will also explore solar, building integrated solar, bio-based materials, nano-technology, sustainable practice and procedures, integrated wind design in roofs and building envelopes, “smart” roofs, cool roof technology, sustainable legislation and its impact back to you, living walls, related water management technologies, energy related items or issues, and carbon impact relative to the roof and built environment - or any other issue that the readers want to explore or my small brain, twisted by an insatiable curiosity wanders into.

I hope to educate, learn, enjoy and explore these ideas and concepts with you. I’m sure to express my opinion but also hope to motivate and sometimes infuriate you with my topics and column. I know the columns I enjoy reading the most are the ones that are informative, helping me do what I have to do each and every day but also cause me to smile, chuckle or just mutter under my breath the famous line from “Everyone Loves Raymond,” expressed so eloquently by Debra, Ray’s wife…….“Idiot!” If you like that kind of column, you should enjoy this one. If you like heavy technical articles, you might not like mine so much, since you should learn something when you’re done reading it but it won’t be mistaken for a technical journal.

What I need from you in this little partnership, is your feedback and ideas on what topics you would like more information on and I’ll try to write about that. In the face of little or no input, you’ll have to read to what comes out of my head and from my vantage point. On this, you might want to talk to my wife, Lea, of 31 years +, as she contends this is not always a pretty sight. She tolerates me, even likes me, and I hope you will do likewise.

Here is a thought to ponder until our next time together. Never mind, that’s your boss coming around the corner and you need to get back to work.

Look for my first “real” column next month.

Ralph P. Velasquez
Director, Sustainable Technologies Group
Tremco, Inc.

P.S. My first name is an old Anglo-Saxon name that means wolf-counselor or wise counselor. Yeah, I chuckled too.

Publisher's Note: It bodes well for The Sustainable Roofing Technologies Editor that his new column was inaugurated on Earth Day, 2008!

Dear Readers,

It has been some time since I last wrote an article on the activities of the ASTM task force group (E.06.71.07), relative to green roofs. I missed the last meetings (April) entirely, as I was out and about taking care of customers and making a living. While the ASTM work is important, even critical, it is done on a totally volunteered basis and can take some serious chunks out of your schedule. Enough whining, we all have our time constraints, you just want to know what did we get done and how can you help me? Right.

The “big” thing on the agenda is the work that continues on the Standard Guide for Green Roof Systems and the Standard Practice for the Assessment of Green Roofs (The Guide). The Guide is the first step in creating a document that covers the “whole enchilada,” giving the designer some direction on what to consider as they practice the art of architectural design, relative to green (vegetative) roofs. By the way, I prefer the term vegetative roofs (VR) versus “green,” since green in my mind is something broader. In fact sustainable roofing is even a better term for “green,” since again it better defines the various attributes of what a particular roof design can contribute to the final decision, other then just environmental impacts. Ah, but I digress, back to The Guide.

The Guide covers the roof membrane, accessory components such as drain boards or root barriers, growing media, plants, code issues, etc. We have made progress on the various categories, however, two of the most critical issues that continue to prove to be a sticking point are the issues of fire and wind. As some of you may recall, in a previous article I raised the issue of wind (see below: "What's blowing in the wind?"), as have others within the industry, and we continue the debate.

Since our discourse on this subject, various stakeholders have begun to grapple with these two issues. The National Roofing Contractors Association (NRCA) has taken a position on the issue, pressing for the fledgling green roof industry to comply with existing fire and wind standards for conventional roof systems, even though applicable testing methodology has yet to be built. The NRCA recently submitted this request to the International Code Council (ICC) for inclusion in the mid-term meetings this past fall and the ICC passed the submission for inclusion into the code. The language will be inserted into the 2009 code approvals book, at which time various public bodies will begin to adopt this requirement. In response, folks like ANSI/SPRI (American National Standards Institute and Single Ply Roofing Industry) and the Green Roofs for Healthy Cities (GRHC) have attempted to embrace the issue and find a solution to the challenges this presents. I think more help will be needed, including from our friends @ the NRCA, who by the way have issued their new guide for VR design considerations (see Industry News for more info about the NRCA Green Roof Systems Manual--2007) .

The technical concerns revolve around issues such as wind scouring of the growing media, growing media displacement, attachment of loose-laid components and fire resistance classifications. Challenges include how one tests for fire resistance when the roof design is in constant fluctuation, i.e.: the various states of wetness of growing media or the various types of planting material. Sedums hold water within their structures, while grasses collect biomass over time and could present a fire hazard. Constant changes in the wetness of the growing media, or depth or composition of the blend, coupled with plant type, irrigation, plant maturity and the like make a test method a moving target. Some agencies such as Factory Mutual Global have issued (Sept. 2006) as a document to their customers to follow (FM 1-35), with their perspective of controlling losses. Some of us in the roofing industry have mixed feelings about FM in the conventional roof arena and this carries over to the VR world as well. Still, it is one way to view how to handle the twin issues of fire and wind.

I think what this entire episode has prompted, is for the green roof industry to get very busy finding the needed answers relative to fire and wind, in a specific time frame, so as not to find the industry stymied from a lack of well defined standards and the needed test methodologies that guide us to achieve the standard. That said, I also believe solutions will be forthcoming, since our European brethren have already gone down this path and the industry is thriving, thank you very much. This coupled with the self-interest of all interested stakeholders has and will drive us to needed solutions.

Well, the work continues, as we strive to assist everyone who wants to do the right thing and design VRs that work, and work as advertised. Come join us in ASTM if you dare but be ready for more work on your plate, being unpaid for that work and a satisfaction that comes from making your industry and the world it impacts, just a little bit better each and every time.

ASTM Task Force Updates, 2006 Fall Meetings – What’s blowing in the wind?

Well everyone, another meeting has come and gone with my green roof brethren, as we completed our meetings in late October. While these meetings can be laborious as we mull through the details, they can also be intensively debated if an unusually important subject is on the table. One such lively discussion took place that I would like to bring to your attention and hopefully get some input.

While our industry is moving rapidly forward and we continue to learn, there are issues that need to be addressed to protect the end user and to ensure the industry will continue to prosper. The issue that caused such a lively debate was wind uplift of vegetative systems.

To the best of my knowledge and to the best of our task force collective knowledge, there are no current codes or guides specific to wind uplift as it relates to vegetative roof design in the US. So, if this is true, then how does one properly design and install a vegetative roof that will not blow off or if not blow off, have displacement of the growing media or planting material? How are issues such as building height or building location & orientation dealt with in vegetative design? Does the soil need to be restrained? If so, then how is that best achieved? Is there liability to the building owner if something blows off and there are not codes in place to deal with this issue? What about who installs the soil? If the roofing contractor installs it, is he responsible? Should a landscape firm install it? Can the landscape firm get properly insured in a roofing environment in order to place the soil? What if some of the soil or plant material goes airborne and hits a building, a window, and a pedestrian?

As one can see there are many questions and no firm answers currently. The ASTM task force has and is grappling with numerous issues in this fledgling growth industry, with wind uplift being just one of those issues. So what is the designer or end user to do before standards are built specifically for vegetative roof systems? I would propose a couple of thoughts and expect many others to have the ability to weigh in on the dialogue.

First, there are many standards already in place for roof design relative to wind uplift and these should be followed. Don’t throw out good roof design just because we are putting soil and plants above it. The one area this may cause a problem is with loose-laid roof systems that typically depend on some type of ballast to keep them in place. Since growing media is not like typical roof ballast in many ways, then design criteria for these type of roofs should not follow the standards set for this type of design. Aggregate based soils have different shape, size, weight and wind induced behaviors of the aggregate then natural stone ballast used in typical roof applications. I would encourage some common sense, where we might look to guides set forth in ANSI/SPRI for ballasted applications but not takes these as interchangeable understandings or approaches when designing vegetative roofs.

Second, the designer should think carefully about issues relative to wind uplift, such as wind zone, topography, building orientation, surrounding buildings impact, edge type and detailing, building height, etc.

Third, the designer should consider the type and typical saturation condition of the growing media being used. Wet media is heavier and typically less apt to be displaced, so if the roof is an area that would be dry much of the time and not irrigated, then wind issues might be more of a concern, then the reverse.

Fourth, the designer should consider the use of erosion control mats and how they would impact the project. The use of a biodegradable mat in the first two years might be sufficient to allow the plants to create a more mature root matrix that would be less prone to displacement or blow-off, with an increased ability to absorb moisture, wetting the soil and making it less likely for displacement.

There are many other issues to consider and this brief column was not meant to address all concerns or even to offer the only solutions. All I wanted to do here is raise the issue, let you know we have and for all parts of our industry to take this into their consideration so as to protect the owner and the industry from any future problems related to wind.

So go forth and change the world one vegetative roof at a time, just check which way the wind is blowing!

Ralph P. Velasquez
Sustainable Technologies Specialist
Tremco, Inc.

Greetings to all of you who are interested in green roofs! We are back from Toronto, Canada where the work continues on developing and in some cases already refining existing standards for this emerging technology.

First, if you are unaware, a new standard has been approved by the committee, made it through review and is now available to the public. ASTM standard E2400-06, Standard Guide for Selection, Installation, and Maintenance of Plants for Green Roof Systems, can be downloaded from the ASTM website for $29.00. Nothing is free in this world and neither is this document. That brings to five, in the stable of green roof documents, available to assist end users, designers and other interested parties. Click on the hyperlinks below for a Document Summary of each standard:

E2396-05 Standard Test Method for Saturated Water Permeability of Granular Drainage Media [Falling-Head Method] for Green Roof Systems

E2397-05 Standard Practice for Determination of Dead Loads and Live Loads associated with Green Roof Systems

E2398-05 Standard Test Method for Water Capture and Media Retention of Geocomposite Drain Layers for Green Roof Systems

E2399-05 Standard Test Method for Maximum Media Density for Dead Load Analysis of Green Roof Systems

E2400-06 Standard Guide for Selection, Installation, and Maintenance of Plants for Green Roof Systems

This new standard E2400-06 provides guidance for the selection criteria for plants to be used on Green Roofs. Primary considerations of this standard include: Design Intent, Aesthetics, Climate (both Macroclimate and Microclimate), Plant Characteristics (including rate of establishment, longevity, disease and pest resistance), and growing media composition. The Standard also provides guidance for the installation of plants for Green Roofs. Methods include: Pre-cultivation or direct plantings such as seeds, root cuttings and plugs. Finally, the Standard provides guidance for the maintenance of plants for Green Roofs.

Work continues on the development of the Standard for Assessment of Green Roofs. A lot of progress has been made on this standard in the last year with many undeveloped sections now having first drafts completed. Getting each section to have initial language built out is one of the more difficult parts of the process. It is like trying to write a new book. When you start the process all you have is a lot of blank pages and an idea. Soon an outline appears, the key points hammered out, then, each and every point needs to be fleshed out. Often along the way the outline changes, usually expanding, as you realize there is more that needs definition.

Finally, you have the first complete draft of the standard. This is where we are in the process at this writing. Next, each section will need to be reviewed, revised, rewritten, reviewed again, revised, rewritten and so it goes on and on until we have something we can all agree on. This is a messy and long process that has proven successful over many generations.

There are a number of additional Standards that need to be developed and I will report more on these in my next report to you. You may also be interested in other related Standards and Working Documents related to Sustainability under the E.06.71 sub-committee, such as Environmentally Preferred Products, Terminology, Data Collection or Sustainable Buildings. If you are interested in work being developed in these task Force Groups check the website for published data or better yet, come join us and be part of the process. The next meeting is in Atlanta on October 22nd - 25th, hope to see you there!

Ralph P. Velasquez

Effective July 2006, Ralph Velasquez is in charge of Sustainable Technologies with Tremco, Inc., as the Sustainable Technologies Specialist heading up their new program for sustainable roofing, waterproofing and building envelope solutions, including green roofs, photovoltaics (incl. BIPV), cool roofing and bio-based materials. Previously founding his company Integrated Building Technologies (IBT), Ralph has been involved in the roofing industry since 1978 with a wide range of roofing experience serving hospitals, schools, universities, industries, major corporations, non-profit organizations and property management companies.

Tremco Inc., located in Beachwood, OH, is a division of RPM (Republic Powdered Metals), providing "Roofing and Waterproofing Peace of Mind" to their customers since 1928. Tremco has long been a leader in the concept of sustainable roofing, with a historical focus in keeping "good roofs good", thereby improving the life-cycle of the roof assembly, forestalling replacement and reducing landfill burdens. Further promotion of this concept came with the advent of asbestos free materials, low and no VOC products, recycled content, cool roof technologies, Energy Star, LEED, Title 24 (CA) and now increased emphasis in vegetative roofs and Photovoltaic solutions.

As a major corporation with construction related activities around the world, Tremco is committed to providing building envelope solutions that will meet the customers need for value driven sustainable solutions. We are committed to building upon our past sustainable approaches, creating new mechanisms to achieve improved levels of sustainability and value for our customers. Contact Ralph at: phone 615.251.3055, ASTMEditor@greenroofs.com or rvelasquez@tremcoinc.com.

ASTM Task Force Updates, November 2005

By Ralph Velasquez

Dear Readers,

The fall meetings for ASTM have been concluded and the process continues. Since our last time together the four standards that were passed in committee have now made their way through the executive chain of command of the ASTM organization. The standards have been given a formal designation and are as follows:

E2396-05 Standard Test Method for Saturated Water Permeability of Granular Drainage Media [Falling-Head Method] for Green Roof Systems;

E2397-05 Standard Practice for Determination of Dead and Live Loads associated with Green Roof Systems;

E2398-05 Standard Test Method for Water Capture and Media Retention Geocomposite Drain Layers for Green Roof Systems;

E2499-05 Standard Test Method for Maximum Media Density for Dead Load Analysis of Green Roof Systems.

While these four standards do not a green roof make, they are the first important steps toward building a stable of documents that can used by all interested parties, when specifying a green roof system. I would suggest you purchase these documents and become familiar with them if you are in the green roof business, as they will likely begin to show up in more specifications.

Future work continues on documents that will deal with the practice of the assessment of green roofs and the selection-installation-maintenance of plants for green roof systems. The assessment document is of particular importance, as it has over arching impact on our fledging industry. This work is slow but each time progress has been made.

Right now there in not much else that I can report but I would like to take this opportunity to encourage you to join us the next time in Toronto, CA. We meet April 23-26, 2006 and would welcome your voice.

Best regards,

Ralph P. Velasquez
President, Integrated Building Technologies, LLC

ASTM Task Force Updates, May 2005

By Ralph Velasquez

Dear Readers,

We are back from the “spring” meeting of the ASTM E.06 Committee on the Performance of Buildings. While the calendar said spring, the weather in Reno, NV was cold and snowing. This was great for meetings that lasted all day, since I was not tempted to go exploring anywhere. Also, since I choose to keep my hard earned money safely in my pocket and not “feed the machines,” this also bodes well for keeping one’s nose to the grindstone. Perhaps this was why we made so much progress this time and passed four new standards for green roofs.

The new standards that have been passed through the task force, sub-committee and main committee, will now make their way through the ASTM executive process and should be published for general use in 3-6 months. The four that have passed are as follows:

1) Standard Practice for Determination of Dead Loads and Live Loads Associated with Green Roof Systems.

2) Standard Test Method for Water Capture and Media Retention of Geocomposite Drain Layers for Green Roofs.

3) Standard Test Method for Maximum Density for Dead Load Analysis of Green Roofs.

4) Standard Test Method for Saturated Water Permeability of Granular Drainage Media [Falling-Head Method] for Green Roofs.

A fifth standard, The Standard Guide for Selection, Installation, and Maintenance of Plants for Green Roofs, didn’t make it through balloting and has been taken back to the task force for more revisions. In addition to these five, we are also working on: A) Standard Guide for Use of Expanded Shale, Clay or Slate (ESCS) as a mineral Component in Growing Media for Green Roof Systems and B) Standard Practice for the Assessment of Green Roofs.

Let’s take a look at one of the standards that passed. Let’s take the first one, associated with Dead and Live Loads Relative to Green Roofs. The scope of this practice is to address the weight of Green Roof Systems under two conditions. First, it will address weight under drained conditions after new water additions by rainfall or irrigation have ceased and 2) weight when rainfall or irrigation is actively occurring and the drainage layer is completely filled with water. The first condition is considered the dead load of the green roof system. The difference in weight between the first and second conditions, approximated by the weight of transient water in the drainage layer, is considered a live load. The practice does not address architectural elements that are not essential components of a particular green roof system and will require calculations by the design professional. Terminology is defined within the document for those unfamiliar with green roof system components and a procedure to quantify these weights is outlined within the standard. The significance of this standard will provide information to facilitate the assessment of the performance of one green roof system relative to another, as it pertains to weight factors

While the various documents have passed, there is room for improvements and no doubt once these hit the market, we will begin to work on various tweaks and enhancements. If you have any suggestions on future improvements, we are all ears; let’s just get these into every day use and measure their results and impact. Better yet, join the process, ante up a membership and come join the fray. Your participation in the process will only make the end results better and that is our objective.

The work continues on a regular basis in between each April and October meeting. In between meetings the “donkey” work is done and at the joint meetings we cobble together to review, debate, dismantle and rebuild the work done between meetings. This valuable process keeps the refining pot boiling until the impurities have been drawn off, with the hope that the remaining document is truly the “precious metal” we all desire. An example of this is my next assignment to build into several sections of the Standard Practice for the Assessment of Green Roofs. I will lay the foundation for my assigned sections, as others have already in other parts of the document and submit my feeble attempts for peer review. This will invite the inevitable changes and enhancements, all the time working to keep one humble from the give and take of consensus building, know as the ASTM process.

Until next time, your humble servant,

Ralph P. Velasquez, President
Integrated Building Technologies, LLC

As a member of the American Society for the Testing of Materials (ASTM) green roof task force, I often get asked, What is ASTM working on relative to this emerging technology? In addition, the market-place is asking for guidance and assistance in dealing with a multitude of issues in the design and installation of green roofs. In discussing this with Linda Velazquez (no relation, I spell my last name with a “s,” not a “z”), the publisher of Greenroofs.com one day, she suggested that perhaps a more effective way of “telling the story” would be through the Greenroofs.com website. I thought this was a great idea, so this is the first of a quarterly update on the ASTM greenroof task force.

First, a little background on who and what is the green roof task force in ASTM. The Green Roof task force (E.06.71.07) is part of the sub-committee for Sustainability (E.06.71), which in turn is part of the committee for Performance of Buildings (E.06). The group is comprised of numerous industry related individuals with a general or specific interest in green roof technology. We have been meeting for a couple of years, continuing to increase the number and depth of stake holders involved in the industry. As is true with all ASTM committees, the group has manufacturers, designers, related association representatives, governmental individuals and a varied assortment of hard working people trying to reach a consensus on a host of topical issues. This process can be long, difficult, frustrating, challenging, exhilarating and rewarding, often all in one single session. Sometimes the process is one step forward, two steps back, then forward again. Ultimately, the process is completed and a document is agreed upon by voting members and becomes part of the ASTM stable of documents to be used by the general public.

With that brief background, what are we up to in the green roof task force? There are a number of documents in various stages of development. Some of those currently being worked on include: 1) The Standard Practice for the Assessment of Green Roofs. 2) The Standard Guide for Use of Lightweight Expanded Shale, Clay or Slate as a Mineral Component implanting Media for Green Roofs. 3) Standard Guide for Selection, Installation, and Maintenance of Plants for Green Roofs. 4) Standard Practice for Determination of Dead Load(s) and Live Loads for Green Roof Systems. There are others that address drainage boards, retention components, terminology, green roof membranes, root barriers and similarly related issues. The list seems to grow and becomes more finitely specific as the industry continues to expand, change and respond to the marketplace.

One challenge for the committee is to get an initial stable of documents built, through the peer review process, modified and voted on to become published without waiting for everything to be built at one time. A concern of the committee is that if only one piece of the assembly is passed, that the design community or general public would perceive that this is the only way to build a green roof, when in fact this may be the furthest from the truth. An example of this would be the issue of water retention. There are numerous ways to achieve this, yet the ASTM committee may soon pass a document that deals only with cup type receptacles. What this document will address is: If you choose to use this approach to address your need for retention, then you have a document that will give you guidance in how to objectively achieve your needs. What it doesn’t address is the other perfectly acceptable alternatives available in the marketplace. This approach was worked on early on in the group and has had more time to get through the aforementioned process and reach publication. Nothing more, nothing less!

As the green roof industry starts to really heat up, the pressure is building for some type of standards to be built to help all interested parties. I hope this brief overview will give you, the reader, the first glimpse into what is coming from the ASTM committee that will help address this need in the marketplace. What I did not want to do in this introduction piece was to get into the technical aspects of the various documents and bore you to death, otherwise you might never come back to our little news corner. To the “tech heads” among the readers, hang with me until the next time, when I promise to give you something more to chew on.

If you have something particular you would like to know about the committee’s work drop me a line and I will try to answer that question in my next quarterly update. The ASTM committee next meets in late April, then again in October. I hope to have an update on our work shortly after the April session.

I would love to answer all inquires individually, so if you are the only that one that reads this and emails me I will respond in like kind. However, if there are a lot of you making inquires, don’t forget I need to make a living and I don’t make that living writing free articles for Greenroofs.com, thus the need to address it in the next quarterly posting! Hope you all understand.

Sincerely,

Ralph P. Velasquez, President
Integrated Building Technologies, LLC.

Ralph Velasquez is the founder and president of Integrated Building Technologies (IBT) and has been involved in the roofing industry since 1978 with a wide range of roofing experience serving hospitals, schools, universities, industries, major corporations, non-profit organizations and property management companies.

IBT is an 8(a)/MBE consulting company dedicated to the advancement of the latest roofing and waterproofing technology through correct analysis, proper design, system innovation, and project management excellence. A firm specialty is the promotion of sustainable roof designs, including greenroofs, that deliver an economically sound, environmentally friendly and common sense approach to the rigorous demands of industrial, educational, institutional and commercial roofing. Contact Ralph at: ASTMEditor@greenroofs.com.

The opinions expressed by our Guest Feature writers and editors may not necessarily reflect the beliefs of Greenroofs.com, and are offered to our readers to simply present individual views and experiences and open a dialogue of further discussion, debate and research. Enjoy, and if you have a particular comment, please contact the author or send us an email to: comments@greenroofs.com.