Image Credit: All photos: Construct Ireland
Image Credit: All photos: Construct Ireland The house was inspired by the old stone barns common to the region and features an open, loft-like floor plan. The double-height, lofted ceilings in combination with exposed beams and fully glazed gable create a light-filled effect.
More Green Building News
Reprinted with permission from Construct Ireland, issue 8, volume 5.
By Tomás O’Leary
The passive house standard is now truly a global phenomenon, and this project is the first certified passive house in New York, a climate which presents the double-whammy challenge of very cold winters and scorching humid summers. Similar to a thermos flask, Dennis Wedlick’s design keeps the indoor climate cool in summer and warm in winter.
What I most like about this single family residence is its utter simplicity in form and design, which in turn helped achieve the passive house standard with graceful ease. The structure of the home consists of A-shaped laminated beams externally insulated with SIP panels. The clever detailing required to deliver this construction method resulted in what might possibly be a world-record level of airtightness, at around 0.15 air changes per hour at 50 pascals. [Ed. – Tim O’Donovan’s house in Timoleague achieved 0.11 ACH – as featured in issue two, volume five of Construct Ireland.]
Extensive south-facing glazing
The entire southern façade is glazed but there is no risk of overheating in summer due to the deep overhang. The building is thus a manifest expression of clever solar design, an approach which has a long history in the U.S. The main living space is double height and the lofted ceilings in combination with exposed beams and fully glazed gable create a light-filled effect. External finishes predominantly include the natural materials of roof shingles and rock cladding, which help to integrate the building into its surrounds in this rural part of upstate New York.
We have recently used this building as a case study in our training courses in New York, especially in the application of the Passive House Planning Package. Architecturally, the project is the epitome of simplicity and provides an excellent reference case when faced with achieving sustainable design in both hot and cold climates.
Tomás O’Leary is a Passivhaus certifier and trainer who serves on the board of the Passive House Association of Ireland.
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10 Comments
What Deep Overhang ?
When I look at the photo... I am not seeing a deep overhang on the south.
I would think that a design like this would have the same summer overheating problem that Katrin Klingenberg reported with her house.
Is it just me?
see lessons learned
https://www.greenbuildingadvisor.com/homes/first-us-passive-house-shows-energy-efficiency-can-be-affordable
Tomas O'Leary
Tomas, I recently stumbled onto a video you made.
Very Nice...one of the most interesting videos that I have seen.
I think North Americans can learn a lot from "the other side"
link to video
https://www.youtube.com/watch?v=4_VN_GnV4u4
link to discussion about video
https://www.greenbuildingadvisor.com/community/forum/passivhaus/22264/another-video
Window Shading
John,
You are right, 2 story south facing glass walls are a problem in the north, there should be shading at typical 8' vertical intervals to block summer sun.
Costs to build
While I support the Passivhaus program and other certifications like LEED, can someone tell me the cost per square ft of this home? The costs for these type of projects are usually not listed as it tends to be higher than most people can or are willing to spend...not to mention that financial institutions will lend for. I recognize that there are significant energy savings, but until appraisers or underwriters properly value those savings it becomes difficult for this type of home to succeed on a larger scale.
Thanks!
Response to Craig Payne
Craig,
The 1,650-square-foot home is for sale; the asking price is $595,000 ($360 per square foot).
According to one source, the hard construction cost was between $330,000 and $412,500 (that is, between $200 and $250 per square foot).
According to another source, the hard construction cost was higher -- $412,500 to $495,000 (that is, between $250 and $300 per square foot).
More information here:
http://hudsonpassiveproject.com/pdfs/Hudson_River_School.pdf
...and here:
http://www.jetsongreen.com/2011/03/hudson-passive-project-new-york.html
Costs to build
Martin,
Thanks for the quick response. Wow, those costs are incredibly high. When I add the 3kw PV system to my prototype home next month in Asheville, NC, which used Eco-Panels SIPS, the home will be net-zero (site). My estimate hard costs, after all rebates and tax credits are factored in should be about $100 per square foot. I hope this can be a reality for many others moving forward as it is not that difficult to achieve.
Thanks,
Craig
South gable glazing
John B and Doug are right, the overhang is inadequate for solar shading by normal standards, though in this case they probably just lowered the SHGC to help with excessive gain. But there's another problem with fully glazed end walls on an A-frame: excessive glare. The 'light-filled effect' is badly unbalanced and exposure for long periods can be seriously uncomfortable for anyone with even a modest degree of light-sensitivity. "Light from two adjacent sides" is the classic layout for good natural daylighting. The A-frame gable window format is all about framing a view: great in its way, for certain purpose, but not the best natural model for human comfort in a home.
Response to James Morgan
James,
This home's extensive south-facing glazing has already been discussed at length at GBA. If readers missed earlier articles on this house, here are the links:
A Passive House Take on the Hudson Valley
Hudson Valley Passive House
For Sale: One Passivhaus, $595,000
@Martin
Thanks for the links back to earlier discussions. The middle item also contains my blunt critique of several other aspects of the design of this home, not just the fenestration strategy.
QAQC is essential for actual performance and happy clients!!
Dennis and his team did a very nice job with this project, no doubt, and have held the title of "First" to my knowledge at least through August 2011 (even though there are many other projects in NY that have claimed for a while to meet the standard or are designed using "PH principles"). PHIUS worked closely with the team throughout the design and certification process until it was fully certified in 2010. This project broke the air tightness record up till then held since 2006 by the BioHaus in MN with 0.18 ACH50. Dennis's project beat it by 0.03. A major achievement. Dennis was in my CPHC class in Golden Colorado, when he got word of it. It was very exciting. It is encouraging to see that the project also gets the well deserved attention and recognition from our European colleagues in Ireland. They are writing about it!
While PH designs in Europe also have a potential to overheat, the designer might not be as sensitized to the importance of shading mechanisms to avoid that overheating simply because there is so much less solar radiation available to begin with. This might explain the author's unawareness of this climate specific fact that impacts the design of a cold climate North American variety so thoroughly. And indeed, as pointed out in the comments, the overhang is too small and does not sufficiently prevent overheating.
The overheating is certainly not optimized. In this case the architecture takes precedent. Who would want to impact the almost cathedral looking elevation with a trellis, venetian blinds or vertical shading elements? Within the European certification protocol there is no reason to refuse certification on grounds of higher than necessary cooling demand as long as it does not exceed the limit.
On the other hand in more severe cases and climates, this points to a potentially major flaw in the European certification requirements for North American high solar radiation climates. Our new verification protocols correct for that now for various climates appropriately. The European certification process has no requirement for exact verification of solar radiation/shading conditions as built! The only criteria limiting heat gain if there is active cooling is the annual cooling demand allowed max. This is clearly an insufficient criteria as this would lead to excessively high cooling demand (and then source energy) even though it could be avoided entirely in most cases by shading measures. At Building Science Corp. summer camp this past August I was approached by a building scientist and rater, who came to me to tell me about "the problem with Passive Houses" (and you guessed right) and that he just had retrofitted a Passive House in NY State with a mini-split to cool the house because it was unlivable in the in-between seasons due to large southern high gain glazing! I was aware of the project, knew that it claimed to be a Passive House while there were a few obvious flaws in the design. Appropriate shading on the south had been entirely omitted. I informed him that we had not been involved in this particular project and that it was not certified to the best of our knowledge. Those stories of course are unfortunate and damage the reputation of Passive House. Missing quality assurance during design and construction indeed can lead to such significant failures which points to the importance of trustworthy qualified third party verification for design and implementation.
Thank you Dennis, for certifying your project with us!
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