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14 Answers

Fireplace in tight house

I have just starting building a new house which will have an Isokern fireplace. The hose will be relatively tight with ZIP sheathing and spray foam insulation. Besides opening a window/door to allow for the fireplace to adequately draw, what is recommended for sufficient air to feed the fire. (Please, no comments re fireplace is not practical in a tight house, etc.) Isokern sells an outside air vent but not sure if that is sufficient or the best way to go. http://earthcore.co/product/outside-air-kit/


In Energy efficiency and durability | Asked By Richard Marks | Nov 29 16
16 Answers

Exterior foam wall assembly without interior polyethylene

I am building a Net Zero home in Edmonton, Alberta Canada and plan on using 6" of EPS or XPS rigid foam on the exterior of a traditional 2x6 wall sheathed with OSB and filled with Roxul batts resulting in about an R-40 wall.

The building code here calls for polyethylene on the interior and a maximum 1/3 rule for insulation on the exterior however the recommendation on this site is at least 4" of exterior rigid foam and no poly for a wall like this(I assume my climate zone is 6). How can I convince the city to accept my design and how can I ensure air tightness without poly?

Thank you.

In Energy efficiency and durability | Asked By Sheffie Kalat | Nov 27 16
7 Answers

How to insulate a screened porch floor

I am looking to insulate the floor of a 3-season porch that is outfitted with removable sashes that will be removed for the entire summer season, thus exposing the floor to some blown-in rain. The sashes will be reinstalled in the fall so that the porch can be used in the fall and spring and will be opened up to the main house to benefit from the heating system in the house.

In Energy efficiency and durability | Asked By Elizabeth Slotnick | Nov 28 16
1 Answer

What is wrong with my gas fireplace?

We have a gas fireplace insert. It will not stay on if the solid glass door is on it. If we remove the glass it will work. We've had a partial inspection done on the control and logs. They seem to think it is not getting proper air ventilation. Would this be due to improper install of liner? would they be something clogging up the liner?
Any thoughts would be appreciated. Our chimney is approximately 40 ft. so we are having a hard time finding someone to look at it.

In General questions | Asked By Linda Wachs | Nov 29 16
4 Answers

Frost on outside of triple pane window

Every so often I notice frost/water (depending on outside temp) developing on the outside pane of my triple pane windows. It's infrequent but will mostly notice it early mornings. Actually, as I sit here this evening (68F indoors, 28F outdoors) the exterior of my windows are frosting up a bit. Interior pane is warm to touch. No moisture problems inside. Air exchange keeps interior moisture around 35-40% in the winter. Moisture (minimal-in bottom corners) only forms on interior windows when it's -10F and below. Thoughts? Thanks.

In General questions | Asked By Matthew Michaud | Nov 28 16
7 Answers

New earth sheltered PAHS construction

I would like all opinions regarding my new home construction project. I have a full 3 days experience learning Sketchup and have managed to put several ideas on paper. Please review my plans...and pick holes in them :). I don't guarantee to change my mind, but I do promise to research varying opinions thoroughly and supporting data would be appreciated.

Mixed humid climate Missouri 39 deg latititude
CoMo HDD 5173
CDD 396
Sunny days 195
Humidity ave 70% 83% AM, 56% PM
111 days rain for 46"/yr
10 days snow for 14"/yr

In Plans Review | Asked By Laurel Davison | Nov 28 16
6 Answers

Insulating a cathedral ceiling

What is the most economical way to insulate an 8/12 cathedral with 2x6 rafters, 1x4 "sheathing" with 4" gaps, no barrier...you can see the underside of the metal roofing? The roof is in good shape so I don't want to remove it. I can fir the rafters and vent if necessary but would rather not vent unless necessary. I plan on installing a wood celing without drywall. The house is in Charlottesville Va which is mixed humid. Sorry if you already answered this but I couldnt get back to the other place I asked it.

Thanks, Richard

In Energy efficiency and durability | Asked By Richard Uhler | Nov 28 16
1 Answer

Can unfaced polyiso be used for radiant heat systems?

I have radiant tubing installed between floor joists. I've placed a foil reflective sheet beneath the tubing and though faced fiberglass insulation is recommended to be placed beneath the foil sheet, I want to use un-faced polyiso boards 3" thick instead. The boards will be exposed to a heated, block wall, basement that is reasonably dry.
I would appreciate your comments.
Regards, JTO

In Energy efficiency and durability | Asked By John Oliver | Nov 28 16
6 Answers

Insulating I-joists in a garage ceiling

Hello. I have been doing some research to insulate a 2 car attached garage with a room on top. Size is approximately 27x27, new construction. This is in zone-6, Augusta Maine region, and code is R30 for floors.

In General questions | Asked By Tony Bouchard | Nov 25 16
6 Answers

I would like to know how install baffles around the rafters of hip roof portion of the roof.

I'm doing quite a few projects in my attic but have run into some snags and figured I'm reading so many articles on GBA, I might as well ask a question here. I'm breaking my questions into parts below and any assistance is appreciated. Before posting here, I did read quite a few forums on GBA about these topics and on other websites. Thanks for any help you can provide!

1) Insulation Baffles

In Energy efficiency and durability | Asked By Josh Z | Nov 27 16
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