SRI Values for Copper Roofing - Old vs. New

A former classmate of mine who is working on a LEED renovation project for Meadors Inc., contacted me recently with two questions. What’s the SRI for copper, and for materials that patina over time do you submit the original SRI value or the aged SRI value for SSc7.2 Heat Island Effect, Roof? I didn't know the answer to either question, but after searching I was able to track down Paul Berdahl of the the Lawrence Berkeley National Laboratory's Heat Island Group, who was kind enough to offer to run tests on a few samples of various ages. You can see how quickly the patina changes in the photo below, where the most recently installed roof is in the background:

Copper Roof Installation - Broad Street, Charleston, SC

Photo Credit: Meadors, Inc.

The results for the samples are as you might expect; the copper has a high SRI when new but quickly loses reflectivity as it patinas with time. Strangely when it gets really old it starts to climb up in SRI value again, though not enough to put you in compliance with LEED's requirements. Here's a table of the results:

DescriptionAppearanceSRISolar ReflectanceThermal Emittance
NewBright Copper690.7580.045
2 Weeks OldBright Copper w/ Slight Smudges620.7290.028
Approx. 1 Year OldBrown w/ Green Flecks20.1760.642
Approx. 5 Years OldBrown40.1900.654
50-75 Years OldBrown w/ Light Green Spots and Streaks140.2450.688

Use the above figures at your own risk (this is in no way an 'official' USGBC accepted set of SRI values), but reason would dictate that most copper roofs would have the same characteristics. The question still remains about which value to use, and that is open to some interpretation.

Credit interpretation rulings for SSc7.2 yielded no inquiries about materials that have a non-stable SRI value. Although this is simple conjecture, given the rapid deterioration in SRI for copper (non-compliant within a year, likely much sooner), I would suggest that this product is not in compliance with the intent of the credit which is to reduce heat islands. Clearly for the majority of the life of the copper roof will help foster heat island issues and not reduce them.

What if there are products that deteriorate more slowly, or even become more reflective over time? If I were to write my own credit interpretation request on the subject, I would propose developing a sort of weighted SRI over the course of the expected life of the product, likely a difficult task. What I mean in simple terms is that if we had a product expected to last ten years with an initial SRI of 100 and an SRI of 0 on year ten then the 'weighted' SRI would be 50 assuming a linear decline (90 after one year, 80 after two, etc.). A product such as copper that has some crazy parabolic arc would probably require an excel spreadsheet (or graphing calculator) to determine the lifetime average, but clearly the number for copper would be so low that it's probably not worth the effort. If you've already been through this situation and gotten an official ruling PLEASE share by leaving a comment!

This post wouldn't have been possible if it weren't for the nice folks at Meadors Inc. agreeing to share the results of these tests with all of you and the guys at LBL for doing the testing in the first place. The projects that spurred this post are two historic renovations in the epicenter of Charleston, SC's historic district, 93 Broad St. and 97 Broad St., hence their restriction to use appropriate copper roofing products. You can view galleries of the projects at the links above. Many thanks!

Commissioning Agent Guarantees LEED Certification


How I Learned to Stop Worrying and Blow Up My Market Share

Yesterday afternoon I received a newsletter from Energy Ace, a commissioning and LEED services firm out of Atlanta, with the headline "LEED Certification, or Your Money Back". Unnecessary comma's aside I found this to be a rather startling claim. Reading further into the release you can actually see the word "guarantee" (gasp!)... Full press release available here. How it works:

"clients must allow Energy Ace to oversee LEED administration, fundamental commissioning and energy modeling for each project -- services that the company provides in-house. After signing a standard service contract, Energy Ace would conduct LEED charettes -- the project phase where sustainability measures are mapped out -- and at that point, if everything looks good and team members are cooperative, the contract would be amended to guarantee certification. If a project misses its LEED target level (like Silver or Gold) or fails to earn certification altogether, Energy Ace would refund its LEED administration fee, which is between 30 percent and 45 percent of its total fees..."

First Take: Pros and Cons

On the pro side, theoretically their market share will increase (probably as much for being the first to offer it as for the peace of mind it will give owners... BD&C already scooped this, and you're reading it here). In addition to new clients, one of the clauses is that their firm must perform what is essentially their full suite of LEED related services instead of just CxA, LEED coordination, or modeling. This additional control helps both their bottom line and their ability to ensure that the project is moving along the right track. Also, by ensuring that at least the first phase of design and analysis has taken place, they have the ability to walk away from the promise if things don't look so good. Figuring out where to draw the line is likely going to be an interesting exercise!


Not having seen the contract itself, I suspect (but can't confirm) that there is a clause in this guarantee that limits possible compensation for a missed target to the "LEED adminstration fee, which is between 30 percent and 45 percent of total fees" ONLY. In other words, this guarantee could potentially limit the owner's maximum compensation for a botched certification to the portion of the fee agreed upon. In a situation where missing certification could mean hundreds of thousands of dollars in lost incentives and countless other damages, does this contract actually serve to insulate Energy Ace from paying for these damages? Will owners see the "guarantee" and sign away their rights, or will they recognize it and demand no such clause be included? Again I should point out that I'm only working from a press release here and have no idea about the specifics of the contract. I certainly don't mean to imply that Energy Ace is actively gaming their clients!

The other big issue here is what does this mean for the other parties involved? Does a guarantee from one party, specifically an administrator who is responsible for overseeing and coordinating the LEED documentation process overall, in any way reduce the liability of the architect, engineers, or contractors involved in the project? I suspect not... Due to the fact that the owner may have signed away his right to collect damages beyond the fee from Energy Ace (again... speculation) they may pursue the other parties with additional vigor.

Obviously Energy Ace would not have the ability to really guarantee the certification unless they agreed to offer true design-build service with complete control over every aspect of design, engineering, and construction. No matter their efforts, a mistake from the contractor on SSp1, Construction Activity Pollution Prevention would mean that regardless of the efforts of the LEED administrator, the project would not achieve certification. This firm has worked on nearly 100 LEED projects to date, and I suspect that they're banking on the fact that as an industry we're over-concerned with missing LEED certification targets, an opinion that I'm increasingly leaning towards. Though there will doubtless be projects that miss their mark, my guess is that over the next few years the volume of these projects will be much smaller than many suspect.

If a project doesn't achieve the certification levels the owner desires they're liable to sue everyone anyway, regardless of what the contract says about guarantees. On the other hand claims that would normally be defended by an insurer may now be void, and the company may have to defend itself. I think it goes without saying that such a claim raises the standard of care, probably beyond what an insurance company is willing to tolerate.

Risk Management at it's best!

Is This Wise?

My guess is that the long term result of this for the company will be that yes, they may have to pay back a few fees over the years, but the marketing benefit and requirement for full services will more than offset the loss. At the end of the day I'm still on the fence about whether or not this is a good idea overall. I'm very interested to hear reader comments on this... please don't disappoint!

LEED Platinum Renovation Publishes Full Set of Documentation!

Thanks to a heads-up from Wes Sullens of StopWaste.Org, Real Life LEED is happy to announce another full set LEED NCv2.2 documentation is available online! To see links to other complete sets of documentation just click here.

1537 Webster - StopWaste.Org

Alternate Headline: StopWaste Stops Waste - Mission Accomplished!

Perhaps equally helpful is a well prepared case study that explains some of the process lessons learned and describes the systems used (they even capture the rainwater falling on the solar panels!)... There's also a great online dashboard showing updated utility use and PV generation statistics for the facility.

The only very small issue I have is that on the 6th page they claim that "As of December 2007, we are proud to announce that we're... the first LEED-NCv2.2 Platinum renovation project in the entire nation." Sorry guys, but that honor goes to my hometown outfitter shop Half-Moon Outfitters, who announced their achievement of a LEED-NCv2.2 Platinum Certification on July 16th, 2007. They took an old Piggly Wiggly turned auto-repair shop and turned that into a super-efficient distribution warehouse, maintaining pretty much all the structure.

Though I had to point that out, I don't mean to detract from the accomplishment, and as I'm sure most of you will agree about feeling grateful for these guys helping to make LEED a little easier by sharing their work. Thanks!

Know of a some project documentation online that I may have missed? Please let us know by sharing a comment... it's the only reason I found out about this, so please help out!