http://www.nesea.org/nesea/passive-house-and-buildingenergy-13/?utm_source=rss&utm_medium=rss&utm_campaign=passive-house-and-buildingenergy-13 We Connect Sustainability Professionals to Ideas and Each Other. Tue, 05 Feb 2013 21:06:59 +0000 hourly 1 http://wordpress.org/?v=3.4.1 http://www.nesea.org/nesea/passive-house-and-buildingenergy-13/#comment-619 marty Mon, 04 Feb 2013 05:14:00 +0000 http://www.nesea.org/?p=7726#comment-619 A couple points.As a newcomer to Passive House, I agree that the performance outcomes are desirable, but I question the rigidity with which they need to be achieved to receive certification. Example: We have a ten inch insulated concrete block ( zero thermal bridging within each block, although some bridges in the 6800 sq ft building) with a steady state R-value of about R-14 that heats and cools for twenty cents less per sq ft than an energy model of that same building built to LEED 3.0 standards with R-54 walls. The block features true insulated thermal mass, with a high heat capacity and a thermal lag time of greater than 50 hours. The R-54 wall was modeled with 10" of concrete exterior and 10" of continuous EPS insulation at R-5 per inch on the interior of the building. I am aware that some PH applications in Europe use insulated thermal mass (and unfortunately ICF's, which block the benefits of thermal mass, and create isolated thermal mass) in PH . Here in the US, the PH designers I have talked to favor SIPS for PH. I have been told that the NRG block does not meet PH criteria, although it will deliver PH performance. In climate zone 6, the insulated thermal mass block thermally outperforms an R-54 wall by a large margin (33 cents per sq ft heating and cooling vs. 53 cents per sq ft for heating and cooling) . Further, with the reliance on super-insulated walls, designers seem to overlook the fact that according to energy models, the performance difference between an R-23 wall and an R-54 wall in climate zone 6 is about 2 cents per sq ft in heating and cooling cost. Where is the payback? Is there a pioneering PH designer out there who wants to be the first to prove that insulated thermal mass belongs in PH in the US? I would love to hear from you. Thanks. Marty A couple points.As a newcomer to Passive House, I agree that the performance outcomes are desirable, but I question the rigidity with which they need to be achieved to receive certification.
Example: We have a ten inch insulated concrete block ( zero thermal bridging within each block, although some bridges in the 6800 sq ft building) with a steady state R-value of about R-14 that heats and cools for twenty cents less per sq ft than an energy model of that same building built to LEED 3.0 standards with R-54 walls. The block features true insulated thermal mass, with a high heat capacity and a thermal lag time of greater than 50 hours. The R-54 wall was modeled with 10″ of concrete exterior and 10″ of continuous EPS insulation at R-5 per inch on the interior of the building.
I am aware that some PH applications in Europe use insulated thermal mass (and unfortunately ICF’s, which block the benefits of thermal mass, and create isolated thermal mass) in PH . Here in the US, the PH designers I have talked to favor SIPS for PH. I have been told that the NRG block does not meet PH criteria, although it will deliver PH performance.
In climate zone 6, the insulated thermal mass block thermally outperforms an R-54 wall by a large margin (33 cents per sq ft heating and cooling vs. 53 cents per sq ft for heating and cooling) . Further, with the reliance on super-insulated walls, designers seem to overlook the fact that according to energy models, the performance difference between an R-23 wall and an R-54 wall in climate zone 6 is about 2 cents per sq ft in heating and cooling cost. Where is the payback?
Is there a pioneering PH designer out there who wants to be the first to prove that insulated thermal mass belongs in PH in the US? I would love to hear from you. Thanks. Marty

]]> http://www.nesea.org/nesea/passive-house-and-buildingenergy-13/#comment-617 Passive House and Building Energy 13 | Eco Custom Home's Newsroom Fri, 01 Feb 2013 22:34:54 +0000 http://www.nesea.org/?p=7726#comment-617 [...] January 30, 2013 By Paul Eldrenkamp Leave a Comment [...] [...] January 30, 2013 By Paul Eldrenkamp Leave a Comment [...]

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