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6 Answers

Taping seams of tongue and groove sheathing

Hello, I am remodeling a powder room in a 1928 brick colonial.

While the wall is open I would like to air seal and insulate the cavities from inside the house.

To the best of my knowledge, the sheathing appears to be 3/4" Tongue and groove. I would like to tape the joints and the areas along the studs with 3M All Weather Flashing Tape. What is the recommended overlap of the tape ? It comes in a 4" width, will 2 inches be adequate ?

In Green building techniques | Asked By Kurt Kiley | Jan 20 15
6 Answers

Renovating an older home

We are renovating our house in North Vancouver, BC.
This area gets about 2500 mm of rain per year.
All the siding is removed and underneath, are 1x8 ship lap boards over 2x4 framing.
I removed the old building paper and covered with Typar for the winter.

I was thinking of installing inch and a half Roxul Comfortboard over top the Typar and under the rain screen but I understand that the bottom edge of the air barrier should not be sealed so that any water that gets behind it, can drain.

However, with the board sheathing, I don't get much in the way of air sealing.
Should I remove the

In Green building techniques | Asked By Aaron Gatzke | Jan 17 15
1 Answer

Blower door test - Des Moines, Iowa

Hi:

I'm trying to help a friend in Des Moines, Iowa obtain a blower door test & follow it up with directed air sealing. How does/should one go about finding a contractor to perform a blower door test? Is there a city/state database of contractors able to perform a blower door test? For renovation projects, how do most contractors who perform blower door tests receive new business? Lastly, what should one look for when choosing a contractor to perform a blower door test and/or air sealing?

Thanks,
Rob
Houston TX

In Project management | Asked By Robert Hallenbeck | Jan 21 15
6 Answers

How do hybrid foam and fiberglass insulation systems work?

My contractor has recently installed a hybrid foam/fiberglass insulation system in my new home. He sprayed 1-2" of closed cell foam between 2x6 studs then finished with paper backed r -24 fiberglass insulation. After covering with drywall and two coat plastering the walls interior paint was applied however, during this time moisture started to leach out of the bottom of the drywall along the outside walls. What is causing this and how do I resolve the problem? We live in upstate NY so the weather can be cold and windy.If you need more info just ask!
Thank you
Brian

In Energy efficiency and durability | Asked By brian Adessa | Jan 18 15
6 Answers

Can an applied veneered cut stone on the exterior of a house in Houston, TX hang over the property line?

Any help appreciated, be it by links, PDFs, response.
Thank you

In Building Code Questions | Asked By Rodrigo Marron | Jan 20 15
7 Answers

Bathroom wall insulation question

My house is in northern Maryland, Zone 4, which has both cold winters and hot humid summers. My house is unusual for the area in that it's built out of concrete block, faced with brick and I have plaster walls with no wall insulation currently. It's built like a cold fortress.

I am gutting my master bath and would like to insulate the walls but fear creating a mold situation. I am reading a lot of conflicting reports on both the insulation type and the placement of the vapor barrier. A lot of this stuff gets over my head and has me spinning in circles waiting to start the project.

In General questions | Asked By Mark Leach | Jan 14 15
3 Answers

What is the calculation method to determine the actual BTUH output of a hydronic radiant floor?

We are looking for a mathematical calculation for determining the actual btu output of a hydronic radiant slab floor in a basement. Any assistance is greatly appreciated.

Thanks.

[The author of this question has asked for his name to be omitted.]

In Mechanicals | Asked By GBA Team | Jan 16 15
9 Answers

My question is, how do I properly insulate from the inside and prevent a mold or rot issue when there is no sheathing?

Hello everyone. I have an insulation challenge that I could use guidance on. I am located in the Midwest zone 6 and converting a 22'x25' 1950 detached garage with a concrete floor into a heated workshop.

In Energy efficiency and durability | Asked By Ell Aire | Nov 8 14
14 Answers

Attic / roof air sealing and insulating

I am a novice DIY trying to avoid mistakes. This house is in Iowa.

I have a house and am renovating before occupying. The first goal is air sealing and the first project was the rim joists.

Now I am preparing to seal and insulate the attic, which I think in this case would require sealing and insulating the roof.

In General questions | Asked By Erich Riesenberg | Feb 13 13
29 Answers

Polyiso for basement

Morning all

I am about to embark on the basement insulation. I have a question about polyiso. After much reading I was so sure about putting xps 2" rigid foam against walls and rim joist.

I read the gba, several other forums and as I understand, the steps are - clean the basement walls, clean rim joist, place rigid foam, seal with great stuff, place xps with foam glue on walls, tape the seams, seal the edges with great stuff, leave a inch gap and frame with stud walls.

In Green building techniques | Asked By sr kod | Dec 20 14
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