orlandoicf
New Member
Posts:26
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| 07 Apr 2009 04:17 PM |
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Looking for feedback on those who have experience with LEED-H certification on homes with ICF walls. We are running into a pushback from the LEED commission agent who is only allowing for the R-value of the 6-inch core ICF walls to be calculated at R-22 - this is the R-value of the EPS foam panels only. This value does not take into account the performance value of the wall's thermal resistance which is much higher due to the thermal mass characteristics of the solid concrete. How do you quantify that for the LEED agent? The new home project is in the upper midwest. |
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icf4life
New Member
Posts:20
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| 08 Apr 2009 05:31 PM |
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How many points are they giving you for the ICF? We did an ICF 4-plex in Minneapolis that gained a gold rating |
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JBACC1103
New Member
Posts:28
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| 08 Apr 2009 07:39 PM |
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What credit are you trying to get? There are alot of different credits available. |
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| It ain't easy being green.... |
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Bruce Frey
Basic Member
Posts:429
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| 09 Apr 2009 06:11 AM |
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I'll start by saying I know little about LEED Homes, but I do have the Reference Guide (mostly unread).
Are you pursuing the Prescriptive or Performance path for Energy & Atmosphere (EA) credits? How are you being scored? Are you looking for points in Innovation & Design (ID)?
I am sure there are LEED precedents about ICFs that I don't know about, but I don't think you are going to get much if any "thermal mass" credit. The studies that I have seen do not support thermal mass benefit in cold climates. There are lots of good reasons to use ICF, but for me, thermal mass is behind reduced infiltration, R value and durability.
I doubt you are the first to use ICF with LEED, so have your AP see what precedents exist.
Bruce
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JakeG
New Member
Posts:55
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| 15 Apr 2009 10:07 AM |
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slightly familiar with LEED ICF home in Minnesota. they have almost completed the process.
try contacting the architectural firm perhaps to get some feedback.
www.rkdarch.com re: Green Fin House. I understand they were going for fairly high ranking on this particular project. I think it was built with Durisol. |
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renangle
Basic Member
Posts:304
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| 15 Apr 2009 10:50 AM |
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orlandoicf,
I have come up across this on a LEED for School project very recently. Our research with several professionals seems to show that there is a flaw in the LEED calculation with regards to the R value under the initial energy efficiency calculation for the energy and atmosphere section of LEED.
What we found is that based on the calculation criteria mandated by LEED, you must look at the R value in the ICF as it sits, thus true performance of the wall is not take into consideration. The calculation is performed on the front end when trying to determine how many LEED points will be acheived. It is our position that once the true calculation of the energy efficiency of the building is calculated (after construction) we will be able to increase the number of points available under the Energy and Atmosphere section.
Others may have come across this, but based on our experience that is how we see it. Hopefully those at LEED will change the calculation criteria. |
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stonecaveman
Basic Member
Posts:123
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| 15 Apr 2009 05:50 PM |
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Could you go for the "Exception Energy Performance" and use a HERS rating instead of using the prescriptive EA? And would it help you if you did? |
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Aaron McKinney
New Member
Posts:56
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| 15 Apr 2009 07:18 PM |
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What agency, or company are you using? |
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ZeroEnergy
New Member
Posts:2
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| 15 Apr 2009 07:29 PM |
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Check out the U.S. Oak Ridge National report on DBMS Dynamic Benefit of Massive [wall] Systems. They built two 1500 sq. ft. identical floor plan homes One with wood and one with ICF plus they did hot box modeling and computer analysis for six different U.S. climates and they did six different wall systems. ICF was one, then they fabricated test samples in some unusual arrangements of foam and concrete, in symmetrical and assymmetrical configurations to really nail down and quantify exactly how much better ICF type construction was in all those different U.S. areas. In Denver an asymmetrical ICF performed 185% better than wood and in Minneapolis it tested as 147% better.
The use of these type ICF panels should enable you to get not only the EA credits, but maybe the ID as well, as there are very limitied number of systems that can be fabricated or erected as an asymmetrical panel. Good Luck ! I am on the AZ USGBC Technical Committee, and I am certainly learning a lot ! ! Don |
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| Donald Eyermann<br>President "Eyedestu"<br>EYErmann DEsign STUdio, inc.<br>Zero Energy Lifestyle Systems Integration<br>480-985-5750 Hm; 480-516-6487 Cell; 480-924-9731 Fax.<br>Innovating efficiency in living working spaces and transport systems. |
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TerryJ
New Member
Posts:40
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| 15 Apr 2009 07:53 PM |
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Donald,
Lets be clear - any modern technique performs better than a stick frame wall. But depending on location SIPs or assymetical ICFs perform differently.
Assymetrical ICF's (concrete on inside/foam on outside) perform best in warm locations (Phoenix>Miami>Atlanta); but in cold locations like Minneapolis, there is no difference in performance between SIPs & ICFs.
In fact all 6 configurations tested performed equally in a cold location.
I am from Canada so the distinction is important to me! LOL
Terry
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Stillable2think
New Member
Posts:4
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| 21 Apr 2009 12:17 PM |
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There is a subdivision in Lincoln City, Oregon that received the platinum LEEDS certification. They used ICFs (polysteel). I think the developer's name was Teeny. |
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Hoowood
New Member
Posts:78
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| 28 Apr 2009 11:03 AM |
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Hi @ All
LEED and the right credit rating is the next big step that needs to be approved. The more this very innovative group here in GBT is planning to implement something that helps the home owner, the invironment and the state, who is makeing trades with carbon credits, the more we must talk to the many organisations and politicians, to change so that we can. In Germany , when you convince the buyer to build really GREEN, the governmentally owned bank KFW gives you up to 65,000USD for a smaller interest rate of 3,5% and no payment for a period of time.
Only these incentives will start the engine for the market and bring back work to the thousends of companies and workers. As long as LEED is comparing apples and peaches nothing will really change. What sense does it make when a home owner invests $400,000 in a home that, once it is finished, will only be appraised $340,000 as I could read here from another forum member.
"We can't solve problems by using the same kind of thinking we used when we created them."
Albert Einstein |
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markever
New Member
Posts:11
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| 28 Apr 2009 02:18 PM |
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This is from the USGBC web site ...
http://www.usgbc.org/DisplayPage.aspx?CMSPageID=1970
LEED Version 3
The LEED green building certification program’s greatest strength lies in its consensus-based, transparent, ongoing development cycle. The next version of LEED is here! On April 27, 2009, USGBC launched LEED v3. The ability to be flexible allows LEED to evolve, taking advantage of new technologies and advancements in building science while prioritizing energy efficiency and CO2 emissions reductions.
FIGURED YOU GUYS WOULD LIKE TO BE ON TOP OF THE NEWS |
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Bruce Frey
Basic Member
Posts:429
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| 29 Apr 2009 04:37 AM |
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Posted By markever on 04/28/2009 2:18 PM
This is from the USGBC web site ...
http://www.usgbc.org/DisplayPage.aspx?CMSPageID=1970
LEED Version 3
To clarify, LEED V3.0 is for New Construction, Core & Shell, Commercial Interiors, etc. LEED Homes will continue in its current form until probably 2011. Hoowood makes a valid point. The approach in Europe is to mandate stringent code requirements and in some cases to find ways to offset the investment with benefits. An example is that projects that I am working on in Milan MUST have some PV (not much in offsetting benefits, though). LEED is not a code, but a "yardstick" or scale for measuring how "green" a building is, which includes more than just energy. It is a private, voluntary system so some level of consensus is required....which tends to dilute issues. Remember that a camel is really a horse that was designed by a committee. One of the more beneficial things the EU has done is to mandate that all buildings must have an Energy Performance Certificate (EPC)..... like when you buy a major appliance. In my commercial building world, this will have an impact on the sale price of buildings. Another major difference between the USA an Europe is the style of housing. Someone on another thread commented that "no house has only 4 corners." While that statement may be true in the USA, most affordable, single family detached homes in Europe DO have 4 corners, are 2 story and square-ish, i.e., efficient shapes. The facade and roof area vs. floor area is a big factor in construction cost and energy consumption. Bruce |
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wes
Advanced Member
Posts:810
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| 29 Apr 2009 06:16 AM |
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Bruce,
Your last paragraph hit the problem squarely. How do we convence the average American home buyer that a minature mansion resembling a French castle, is not going to be 'green', no matter what materials its built out of. So many times, I hear clients say 'I want to save money, so lets cut the square footage'. When you try to explain that square footage isn't their main problem, they look at me like I'm nuts. The 'square foot' cost is so ingrained in the American psyche that we cannot understand that if a 4000 sf home costs $200 per sf, then why can't you reduce the sf to 3000 and save $200,000.
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| Wes Shelby<br>Design Systems Group<br>Murray KY<br>[email protected] |
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Hoowood
New Member
Posts:78
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| 29 Apr 2009 01:19 PM |
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Maybe the rocky mountain Institute can help here too
http://bet.rmi.org/our-work/awards-and-recognition.html
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