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12 Answers

Woodstoves: does efficient burning depend on size?

We are in the market for a new, non-catalytic woodstove. We understand that a non-cat stove needs a minimum temperature of around 500° for an efficient secondary burn. Question: Does attaining that 500° depend on the size of the stove at all? Or will the same quantity of wood produce the same burn temperature regardless of firebox size? (I know, dry, seasoned hardwood, etc.)

In Energy efficiency and durability | Asked By Patricia Appelbaum | Dec 17 14
10 Answers

Rigid insulation

Builder put rigid insulation on the exterior of the house.
But it is not sealed! Should they have put metal flashing on first?
Picture is looking up foundation wall, insulation, siding.

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In General questions | Asked By Shawn Ward | Dec 16 14
5 Answers

What is the best way to insulate our new home?

After reading several of the articles on insulation of walls and vaulted ceilings lately, I am a bit confused. We live in SW Montana. Part of the home includes a vaulted ceiling in the great room, the rest of the ceilings are standard 8' heights. The plan calls for 2x8 rafters in the great room. My plan was to 6" bats in the ceiling, then cover with closed cell rigid board (up to 2 ") then gyp rock to achieve a decent R value. Likewise, the walls are 2x6 so planned on batts with closed cell on outside and then installing cedar board/batten.

In Energy efficiency and durability | Asked By richard fasching | Dec 17 14
1 Answer

Since drywall has a permeance of 0.02 liter/sec - m at 75 PA is ever possible to have sheathing dry to the interior of the home?

When constructing a new home most professionals recommend not have impermeable insulation or other materials on both sides of the sheathing. It is recommended that the sheathing should be able to dry to the exterior or interior of the home. If foil faced polyiso rigid foam is used on the exterior of the plywood sheathing and 6 inches of open cell foam and drywall is used on the interior of the home, will this configuration allow the home to dry to the interior? Considering the permeability of drywall will it ever allow drying to the interior of the home with any type of insulation?

In General questions | Asked By JOSEPH POLAND | Dec 18 14
10 Answers

Foam insulation and vented attic

I am in the process of buying a house with open cell spray foam on the attic roof. The vents were left open for gas combusting furnaces. We are in Austin, Tx.
My budget to address the problem if there is one should be enough to cover any number of scenarios.

In Green products and materials | Asked By Heidi Hicks | Dec 16 14
27 Answers

B&G's low flow Vario ECM circulator - stupid efficient pumps

http://bellgossett.com/pumps-circulators/small-circulation-pumps-booster...

What I discovered as a result of the research stimulated by this GBA dialogue is that my circulator controlled hydronic heating will not work with a smart pump like the Alpha, Bumble B or the new Taco model.

In General questions | Asked By flitch plate | Dec 16 14
25 Answers

Foam-free builds

All the talk about sub-slab foam levels has me thinking. What floor systems easily allow foam free construction? Pier construction immediately comes to mind, but beyond that?

In General questions | Asked By Malcolm Taylor | Oct 4 14
6 Answers

Retrofit insulation of an exterior wall

I want to insulate my exterior wall and have the room gutted. I am in the Poconos of Pennsylvania and in Zone #5 I believe. I have 2x6 walls with Tyvek wrap, OSB siding and vinyl siding. The walls had R-19 faced fiberglass batts that were installed poorly. Currently all of the wall cavities and studs are exposed and are in perfect condition. The studs, tyvek and insulation have absolutely no moisture issues at all. They look like the day they were installed 22 years ago. I want to insulate but have questions about vapor issues. I sealed the rim joist with closed cell spray foam.

In General questions | Asked By John Divincenzo | Dec 17 14
7 Answers

Housewrap under vinyl siding

Ok, I'm getting educated and made some decisions. To recap, I'm residing with vinyl after stripping down to plywood sheathing (1/2" plywood over 2x4 studs, fiberglass batt, poly vapor barrier, sheetrock, zone 5). I've decided to go with 3/4" rigid foam over the plywood and under the vinyl which is R3 and very water vapor permeable. Can only fit 3/4" thickness insulation board (long story). Probably going to use Progressive Foam HalfBack H2O with water management system (grooves toward sheathing to drain any leaked in water). Want to add house wrap (Tyvek or Typar).

In General questions | Asked By george baloga | Dec 17 14
29 Answers

Any experience with an unheated (but insulated) slab as a finished floor? Will it be uncomfortably cold?

We are building a 1000 s.f. single-story home in Northwestern Ontario (climate zone 7) on a very tight budget. It will be well-insulated (walls R-40, roof R-60), and have triple-glazed windows, etc. An energy efficiency consultant calculated our heat loss as 16,800 Btu/hr at -32.8 F. The foundation is a short ICF stem wall with a 4" concrete slab (R-20 insulation underneath). Heating will be accomplished with the combination of a high-efficiency woodstove and electric baseboard, and we might add a mini-split down the road.

In General questions | Asked By Beth Turner | Dec 11 14
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