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1 Answer

Leaving rockwool exposed in basement ceiling

Hi. A few places in my basement ceiling cannot be finished with sheetrock: above the electrical panel, the concrete block wall behind the boiler, etc, due to too many pipes or electrical conduits converging. Yet I still need to maintain a fire-rated ceiling in those locations. The building inspector suggested I pack those locations with rock wool.

How can I do this and not have an eternal sprinkle of rockwool fibers raining down on me under these locations? Just curious what other people have done.

Asked By Theodore Theodore | Jan 24 17
2 Answers

Are polyisocyanurate materials considered vapor barriers and to be avoided for insulating basements?

I live in Central Minnesota. Our home was newly built roughly 3 years ago. It was not insulated on the exterior, but foil-faced DOW Thermax Sheathing was installed on the entire basement interior. This has a permeability rating of 0.03. This is basically an impermeable material. If we want to avoid moisture problems when finishing our basement, do we need to take this down and put up something with more permeability like EPS? We do try keep the humidity below 50 or 55 degrees in the basement.

Asked By Andrea Zimpelmann | Jan 15 17
7 Answers

Need 2 foot square of vapor barrier

I'm planning to take out the 50s era milk chute in our house tomorrow. This will leave me with a whole between 12-20 inches square. I'll put plywood of the same thickness and vinyl siding.

I'm fine on the vinyl siding and sheathing, plus a piece of fiberglass and then drywall. For all I have pieces of leftovers or can buy in small quantities.

I'm stuck on what goes between vinyl and sheathing. I don't want to buy a huge roll of tyvek for such a small area. I need this for tomorrow, day after at the latest.

Ideas? Suggestions? Thanks!

Asked By Jeremy M | Jan 20 17
2 Answers

Continuous back-up?

I am trying to understand the fire code here:

I want to put up some hardboard to cover ridig foam in my basement walls. What does the code mean by "3 mm thickness over continuous back-up?"

9.29.7. Hardboard Finish Material Standard

1) Hardboard shall conform to CAN/CGSB11.3-M, Hardboard. Thickness

1) Hardboard shall be not less than

a) 3 mm thick when applied over continuous back-up,
b) 6 mm thick when applied over supports spaced not more than 400 mm o.c., and

Asked By Marc Delisle | Jan 12 17
1 Answer

Fan efficacy and ERVs

what classification does a erv/hrv have if it doesn't have a ECM motor
it is not exempt from the efficacy requirement. so, does it a bathroom utility roon fan efficacy

Panasonic whisper comfort erv uses an ac motor .\
its fan efficacy is 40 cfm@ 0.1 esp/ 23 watts = 1.75 ?

Asked By Kevin Mick | Jan 11 17
8 Answers

How to insulate basement interior (with 2" XPS on the exterior)?

Hello. I am planning to finish my basement and I have a question regarding the interior insulation. The house was built in 2001 and is located in RI (Zone 5). The basement has poured cement walls (12" thick), 8 feet tall. The below grade portion of the walls has 2" XPS on the exterior and the above grade portion (about 2 feet) has no insulation.

Given that I have R-10 on the outside, my understanding is that in order to meet code

Asked By George M | Jan 3 17
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?)

Asked By Michael Chandler, GBA Advisor | Dec 2 16
4 Answers

Difficult building inspector

Needless to say our Building Inspector is real charmer, and on top of that is very unfamiliar with energy smart building techniques. We are putting up 3" of Roxul comfortboard followed by 1x4 furring strips and Hardiplank fiber cement siding. The inspector wants proof from James Hardie that this method is acceptable and safe. We sent him this document from Roxul where they had Building Science Corp conduct a study on deflection using our exact cladding system.

Asked By Brian W | Nov 21 16
13 Answers

Insulation on exterior and interior

My house was built in 2009 in climate zone 6. It has a poured concrete foundation with R-5 XPS exterior insulation. Currently there is no insulation on the inside.

I am planning on finishing my basement and am curious on what the best way to insulate the interior would be. I spoke with my city inspection department and got some conflicting information on energy code compliance. One inspector advised not to add any additional insulation and the other advised 1"XPS with a 2x4 uninsulated studwall was sufficient but the XPS was not totally necessary.

Asked By Nick Collins | Nov 14 16
7 Answers

Treated or untreated top plate?

Which provides the best attachment for a top plate for a concrete core (ICF) wall?

A foam sill gasket will be used between the raw concrete and the wood top plate to provide a break.

Hearing two sides. Some claim a treated top plate provides better rot protection, especially as the concrete cures in the wall. The other side is that a treated 4x6 piece of lumber will not provide as much screw bite and remain true & straight as an untreated 4x6 Doug Fir would.

Out here the treated lumber is the brown cote lumber. It does have a tendency to split as the chemicals leach out.

Asked By Peter L | Nov 8 16
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