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3 Answers

XPS or EPS?

My builder is going to use 5 inches of EPS rather than 4 inches of XPS on the exterior walls. His reasoning is the same insulation value for a little less money ....any pro's or con's either way?
Thanks,
Bob

Asked By bob holodinsky | Apr 15 14
2 Answers

A New Way to Duct HRVs revisited

Hey everybody,
I find Martin's article A New Way to Duct HRVs pretty fascinating. It seems pretty sensible for a well sealed/insulated home, however the postscript from Dr. Straube says that 10cfm of conditioned air wouldn't help with regulating the temperature in a closed off bedroom. I guess that makes sense at that rate.

Asked By Michael McNulty | Apr 14 14
2 Answers

About to break ground, would like to hear feedback on design

This will be located in SW Colorado climate zone 6B (ICC zone 5B). Long axis due east-west with a 45 deg bend on the west 1/3. Attached is a pdf of a typical cross section of the proposed design. I will have some specific questions forethcoming but this is partly a test to see how the pdf looks posted.

Asked By Chuck Jensen | Apr 12 14
1 Answer

Looking for nighttime ventilation that is quiet

I have an 8 year old structural-insulated-panel house. It is tight, has good siting, big roof overhangs and performs well with passive heating and concrete floor hydronics. It has no air conditioning. In my climate we can get a week of 110 to 115 degree highs and 70 degree lows when the small whole house fan makes it difficult to sleep due to noise.

Asked By Joel Levine | Apr 14 14
1 Answer

Can I blow in insulation above Homasote ?

I have a cabin that has a 1/2 inch layer of Homasote as the ceiling in the main living area. We just added heat and air conditioning and I wanted to blow in Insulation (cellulose) in the 5 1/2 inches above the homasote. Will this cause excessive moisture to accumulate and will the Homasote bulge from the extra weight and humidity. I found a product at Lowes that is 3 1/2 fiberglass insulation covered in plastic on both sides that I might be able to get down there. Would this be a better idea? The cabin has a metal roof with no eave vents or ridge vents. Thanks

Asked By Rob Beaumont | Apr 14 14
13 Answers

A low slope, cathedral roof in Zone A-4: builder says he can vent it

Hi! I've been following a variety of discussions about ventend/unvented assemblies in cathedral ceilings, in low slope roofs, in different climates, on FHB, JLC for close to two years. I’ve read Martin, I’ve read Lstiburek, I’ve talked to the architects (hopeless) and structural engineers. I thought I had this nailed down, and now the builder (who also happens to be a SE - long story), comes at me with a new idea.

So I’m finally going to “vent” my worries and seek some advice specific to our situation.

Asked By Michelle Paninopoulos | Apr 7 14
6 Answers

Building it backwards

This rambling old farmhouse in rural Maine has an attached 3-bay garage that connects to the kitchen. The garage has a two-bedroom, seasonal or guest apartment overhead, so it is a large structure, with 2X4 studs.

Asked By Roger Woodbury | Apr 12 14
1 Answer

Duplex house plans

Does anyone know of any links to energy efficient duplex house plans? Preferably something compatible with passive house or similar low-energy paradigm... thanks in advance!
p.s. Martin posted a link to a similar question of mine but they were all SFD plans..

Asked By erik olofsson | Apr 14 14
5 Answers

Cathedral celling insulation technique in a northern climate

I have seen a few discussions about insulating cathedral ceilings but none that relate to the method that I had in mind for my 24' cathedral here in Vermont.
* Penetrating water sealer on all surfaces that have the potential to rot.
* One inch strapping to create an air gap for ventilation.
* Multiple overlapping layers of ridged foam(open or closed cell?)
* All seams taped because expansion and contraction will break a DIY spray foam seal.

Asked By Gary Spurling | Apr 11 14
1 Answer

Lunos eGo Now Available

Has anyone seen a review of this new HRV?

http://www.foursevenfive.com/index.php?main_page=product_info&cPath=70_7...

Although it is rather expensive, installation is dead easy and mechanically it is exactly what I've been waiting for for 35 years.

Consider this... when the occupants are active in the main living area, exterior doors probably get opened and closed a few times every evening bringing in significant fresh air. (This is an impossible calculation, but could be verified through measurement)

Asked By Kevin Dickson, MSME | Apr 11 14
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