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1 Answer

Flame Spread rated spray foam?

I heard yesterday about a new spray foam product that had a flame spread rating that met code without the application of an additional coating - Apparently it is a distinctive color so building inspectors can recognize and sign-off on it.

Does any one have any info on who is producing this product and how the pricing compares to foam with flame spread resistant paint applied after installation of the foam? Does it contain halogenated flame retardants? Is information available on what the flame retardant used is (TPP? or TCPP?)

In Building Code Questions | Asked By Michael Chandler, GBA Advisor | Dec 2 16
12 Answers

Turning a previously enclosed porch into a bathroom- how to insulate slab?

I am renovating an old house in Climate Zone 3. A previous owner turned an enclosed porch into a study. It has a concrete slab on grade floor, stone columns, and a low brick wall at its perimeter. The exterior finish is a layer of Celotex (I am assuming this is an insulated board) and stucco and the wall cavity as constructed is about a foot thick. It is sort of framed up as a double wall. There is an almost 5 inch step up into the adjoining room, so I have plenty of space to build that floor up with insulation. I want to finish the floor with tile.

In Energy efficiency and durability | Asked By Helen Reinecke-Wilt | Nov 30 16
21 Answers

Daylight basement insulation - exposed XPS and other questions


I’m about to insulate the floor and 2 walls of my walkout/daylight basement, and I was hoping to get a little advice on a couple of points I’m not clear on. I’ve researched quite a lot, and learned a lot on this site, but I’m still not sure on a few things. Any help is much appreciated.

In General questions | Asked By Aggy Clayton | Oct 28 16
7 Answers

What direction should I go with my new/used home?

I purchased a 23 year old home to accommodate my growing family. It was constructed with double wall construction, wood foundation, Envirovent system etc. We live on Nantucket Island.
I am planning to install a mini split system and have questions on further improvements, possibly solar, that are upcoming.
My first inclination was to update systems based on the recommendations of local hvac contractors until I realized that my new home is unique and that I might need specialized consultation from someone more familiar with this "type" of home.
Any advice or suggestions are welcomed.

In GBA Pro help | Asked By todd stout | Nov 29 16
7 Answers

Insulate basement wall with half wall, brick exterior, and dimple mat

First of all, this site is incredible! I've spent countless hours reading through threads related to my current project and many others. Thank you all for providing this amazing resource.

In Energy efficiency and durability | Asked By Carlos Moreno | Nov 28 16
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
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