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5 Answers

Why is my canned spray foam product inconsistent?

I'm using Great Stuff Pro spray foam (windows & doors, as well as gaps and cracks) with the Pro 14 gun, and I keep getting the same problem occur. The first 10-20 linear feet or so I spray out of a fresh can seems to come out of the gun really well, but when it drys it'll get super hard and crumbly. After the first 10-20 feet it comes out of the gun super slow, and cures more like it should. So I ether get good application, poor end product, or vice versa.

In Green products and materials | Asked By Adam Peterson | Dec 4 17
6 Answers

Removing stapled kraft-faced fiberglass batts

I have an attic with Kraft Faced Fiberglass Batts that are stapled between the joists. I'm looking to air seal the attic floor but this will entail ripping the kraft facing in order to remove them.

Am I better off leaving it alone and not ripping the paper (I know it acts as a vapor retarder) or does it not really matter if I rip the paper where it's stapled and then just place the batts back in between the joists after air sealing?

Thanks for the input!

In General questions | Asked By BuildingNewb | Dec 6 17
14 Answers

Dense-packed cellulose in attic rafters with Ice and Water Shield on exterior

After having an energy audit perform, it was recommended that I have the attic rafters dense packed with cellulose opposed to insulating/air sealing floor in order to bring the HVAC equipment up there into the conditioned space. Also, 3 cathedral ceilings going into the attic made doing the floor too challenging.

In Energy efficiency and durability | Asked By BuildingNewb | Dec 5 17
1 Answer

Exterior wall options for southern Manitoba

Good evening we are in the planning stages of building a new house. The builder has given us an option of 2x4 walls in the build. They can be upgraded to 2x8 with staggered 2x4s, or a double wall system 2x6 with a 2x4 wall. What would be some recommendations. I like the idea of the larson truss system. Would they build a interior 2x4 wall then add the larson system to the outside? What could be the potential cost differences between each option. I am curious about the R value for walls ROI.



In Green building techniques | Asked By Bryonfriesen | Dec 5 17
5 Answers

Can closed cell spray foam be used to flood proof a wood framed plywood sheathed wall?

I am rebuilding a small building that was flood damaged by Hurricane Irma. I can not practically raise the floor. I was wondering if the interior was finished with PVC baseboard and the stud cavities were insulated with closed cell spray foam would this prevent me from having to remove the drywall and wet fiberglass insulation if it floods in the future? Would the plywood sheathing and framing be able to dry? The exterior wall assembly is 1/2 exterior plywood covered with #15 felt and hardiplank (no rainscreen). Any suggestions are appreciated

In Energy efficiency and durability | Asked By Anthony Swoope | Dec 4 17
2 Answers

Looking for a filler for wood flooring

My renovation/addition of a 37-year-old summer camp included installation of radiant heat and sanding of the existing yellow pine flooring. The structure had never been heated until this season and I expected some shrinkage. Now two months into the heating season, the gaps, though spaced 18" to 3' apart, are predominately 1/8" with one 6' length at 3/16". Obviously, I underestimated the moisture content of the wood.

I would appreciate input on whether a reliable, flexible filler is available that will be compatible with the clear, Bona Mega Traffic finish that I used.

Thank you,

In General questions | Asked By John Oliver | Dec 4 17
5 Answers

Rim joist insulation: What did the builder do?

I am working on finishing my below grade basement in southern Minnesota. Home was built in 2014. I have been planning to hire professionals to spray 2" of foam along my rim joist. Upon further inspection I have noticed that the builder insulated the rim joist.

From the outside in: 1 1/8" thick manufactured rim joist material. 1" of foam insulation (appears to have some kind of front and back facing). 1/2 piece of OSB which is visible from the interior.

In General questions | Asked By BobTheWeekendWarrior | Dec 4 17
1 Answer

Goop and plastic - yes, no, maybe?

Hi Guys,

I'm at the stage of my project where I am installing drywall. Wall is 2x6, Roxul insulation, Certainteed MemBrain smart vapor barrier, and I'd like to do an air tight drywall approach for drywall installation.

But - I've got plastic stapled to my studs, top plate, bottom plate, window rough in, etc. ADA guidelines say I should be caulking all of these areas when I install the drywall, but, um, there's plastic there.

I've only got one small corner complete, my "trial corner" with a window to see how things would play

In General questions | Asked By Tony Bouchard | Dec 4 17
10 Answers

Estimate kWh electricity needed to heat new addition?

I am planning to expand an existing room in my house. The room is currently on a separate heating zone (oil heat, forced hot water). I have solar panels and generate an average 1700 kWh electricity per year more than I use (this is a 3 year average). So I am thinking of heating the remodeled room with electric baseboard, hoping that I can essentially heat it for free with the excess kilowatts that I generate. But I would like to project how much electricity will be required before making a decision. Can this be estimated?

The room will be 13' x 17' (221 square feet).

In GBA Pro help | Asked By user-6963772 | Nov 29 17
8 Answers

Foil vs Bubble Foil or Foam Foil

Hi I'm insulating a shed-like structure on my property to create a comfortable living space. With regard to the tin roof I've been advised to use a layer of Bubble foil on the battens directly underneath the tin and then below that in the remaining ceiling space (above the plasterboard) Fibreglass batts. My question is: In this kind of context will bubble foil give an improved insulating performance over and above foil (sisilation) on it's own directly under the tin? i.e. Is bubble foil worthy of the added cost??

In General questions | Asked By AussieQ | Nov 15 17
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