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10 Answers

Which gas furnaces are most efficient in their use of electricity?

I am about to replace a 13 year old 120,000BTU furnace with a much smaller unit that will be less noisy.

I understand that the fans of these units are a significant power draw. The state of MA will give the same rebate to all 95%AFUE furnaces. Is there a difference, where some brands of 95% AFUE furnace will actually use a lot less power?

FYI my furnace is in the attic so I will end up putting in a horizontal downflow unit.

In Energy efficiency and durability | Asked By rich cowen | Nov 16 17
5 Answers

Detailing a chimney

I know, I know---if I really wanted to be efficient, I would eliminate the chimney. However, I love a good fire and the warmth from it. So, my new house will have a zero-clearance wood-burning unit (RSF 320).

The chase for the chimney is mostly inside the envelope, except for a portion at the top. I have attached the rendering to show what it looks like from outside.

In Energy efficiency and durability | Asked By Kevin Spellman | Nov 21 17
8 Answers

Insulate a cabin to last

Martin - I've learned a tremendous from you & GBA. This is a 1st asking a question. I'm also an engineer & lic Home Inspector, and I see what happens to homes.
I'm current building a cabin in northern Hayward, WI (Zone 7). I'm on a slab, 20'x26', 1 1/2 story, 2x6 walls 16" OC. I had a local carpenter put up the shell, and the rest is up to me. The cabin is sheathed in OSB, Tyvek, Fascia/soffit, and Anderson windows & door are in. I installed kraft faced R19 Batts in the walls (drywall & siding are not yet installed).

In Energy efficiency and durability | Asked By Dan Musielski | Nov 16 17
6 Answers

Carpet on concrete slab--vapor barrier?

We are working on a :budget restricted" fix-up of a house near Dayton, Ohio (Zone 5). The house is slab-on-grade with solid masonry walls (we are adding 1.5" of polyioso to the interior of them). The floor is concrete slab on grade, and has had asbestos and then vinyl tiles applied to it in the past, and most recently had carpet over this. When I tore out the old carpet it was quite filthy, but I can't say I saw any visible mold, etc. on the surface or backing.
Approximately 75% of the slab is covered with these tiles, and the rest has various amounts of mastic or glue.

In General questions | Asked By Mark Waldron | Nov 20 17
6 Answers

Chimney chase condensation

Hello All,
Classic problem I believe.

I have a wood framed chimney chase which houses two 8" insulated, stainless steel metalbestos wood stove pipes and my main DWV stack. On certain days, when the inside/ outside temps, and the relative humidity are just right, I have condensation build-up and dripping from the underside of my chimney chase roof.
Construction detail:

6x10 timber rafters 36" (on center)
2 x 6 rough sawn decking (not T&G)
Grace Tri-Flex
3 layers of 3" Polyiso foam board
2x6 Sleepers 36" (on center, screwed to rafters below)
3/4" T&G OSB decking

In GBA Pro help | Asked By Dave Cummings | Feb 16 12
7 Answers

Attic fan for ventilation in winter?

I have ice buildup because of heat escaping and melting snow and causing ice buildup on my gutters. I have vented gables on both ends of my attic in a split foyer home. Can I install of ventilation fan and set the temperature at say 40 degrees to move that warmer air out and avoid the ice buildup??
Any advice is greatly appreciated... Mike F

In Energy efficiency and durability | Asked By Feiks | Nov 20 17
8 Answers

Best way to insulate attic

My attic currently has R19 foil faced fiberglass batts installed. I would like to air seal the entire attic and re-insulate with blown in cellulose.
The original plan was to cut EPS to fit between the stud bays and seal with great stuff, followed by the fiberglass and blown cellulose. From my understanding, EPS or any rigid foam is not worth the labor for this particular application.

Should I remove the fiberglass batts, caulk/foam the seams and openings, and then reuse the fiberglass followed by cellulose?

In Energy efficiency and durability | Asked By craziekeiichi | Nov 13 17
16 Answers

Petrol-free home: Petrol-free housewrap

So I've got a plan that promotes petrol-free materials throughout the lion's share of the rehab of my shed, which is a lead-in project to the rehab of my house. It involves now a metal roof; Pavatex as a insulation above the roof rafters and Roxul between the rafters; Airkrete in the wall cavity; and Foamglas beneath the Rosendale Cement-based concrete slab.

Main remaining urgent challenge to get the plans to the buildings department ASAP as far as I can tell: "house wrap" "vapor barrier" situation.

In Green building techniques | Asked By Gregg Zuman | Nov 15 17
4 Answers

Sliding patio door track

I have a question regarding our sliding patio door. We had hard driving rain over the weekend. I noticed a small amount of rain water in the track of the sliding glass door. Not much, was able to wipe up with a paper towel.
Should rain water be on the interior side of the sliding door track? According to comments from the manufacturer, the answer is yes. Just doesn't seem right to me.

In General questions | Asked By Birdie L | Nov 20 17
2 Answers

Product thoughts

In my quest to build, I would be interested to hear any feedback or criticism around the Thermobuilt system. ( http://www.thermobuilt.com/ for reference. I am not affiliated. )

I don't really have a specific question. It's always nice to hear input from to professionals on this site revolving around products.

Green-does this use nasty blowing agents? The product appears to be type 1 EPS. Good product? Something worthy?

In Green products and materials | Asked By Drew Baden | Nov 20 17
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