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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.

In Green building techniques | 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.

In Green building techniques | 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..

In General questions | 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.

In GBA Pro help | Asked By Gary Spurling | Apr 11 14
1 Answer

Lunos eGo Now Available

Has anyone seen a review of this new HRV?


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)

In Mechanicals | Asked By Kevin Dickson, MSME | Apr 11 14
3 Answers

Attic Insulation with a Wood Shingle (Vented) Roof

Saw this site form Dan Houlihan of HeatingHelp.
I have a 1917 home in Detroit, Mich that I am renovating. It has a American Thatch" or "Smurf" cedar shingle roof with an open stringer deck underneath. These must be vented on the underside to allow the shingles to dry. Currently there is no insulation. The floor that the roof encloses is livable space, but I will demo all of the plaster walls for insulation access. I have 8" rafters

In General questions | Asked By Mark Reynolds | Apr 10 14
1 Answer

Seal a new slab for wood floors?


I just installed a new slab. Slab is approx 5" thick, and was set up as follows. We dug trenches and laid drain pipes in gravel, fabric wrapped, etc. On top of that another layer of crushed stone, 2" insulation and then a fully waterproof layer (Grace Pre-Pruf). On top of that poured the 5" slab.

Plan is to put down pressure treated sleepers, with t&g plywood on top and then put an engineered wood floor on top of that.

In GBA Pro help | Asked By R W | Apr 11 14
57 Answers

How to insulate with furnace in attic

I am currently looking to put forced air heating and air conditioning into my house. I am located in Long Island, NY in zone 4a, right on the border of 5a. We recently gutted the entire house down to the studs and we are replacing the whole heating system. We will be using gas heat. The contractor that I think we are going to go with is going to install a furnace in the basement for the basement and ground floor, and a furnace in the attic for the second floor. Well also have a blower in the attic for the air conditioning.

In Energy efficiency and durability | Asked By Kevin Schramm | Sep 3 13
2 Answers

Roxul stone wool batts


Looking to use Roxul stone wool batts in the ceiling area. Anyone here know about any air quality testing with these batts? Even though it will be behind 1/2" drywall, are there any issues with the fine particles from the batts or any off-gassing?

In Green products and materials | Asked By Peter L | Mar 31 14
6 Answers

Noisy gas hot air system

It sounds like the makeup vents are making noise (according to my wife). Could this be due to a dirty filter starving the unit of air? Filter is 5 months old. Thank you

In General questions | Asked By Kenneth Clement | Apr 9 14
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