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9 Answers

Bottom edge of rigid foam on basement wall

I'm going about installing 2" or 3" of XPS 4x8 sheets on my basement walls and then installing 1x3 firring strips across the top. I'm wondering if I should bring the foam all the way to the basement floor, or leave a gap and fill the gap with expanding foam. My vote is the first method, but I think maybe the gap with expanding foam may be a tighter seal.

Asked By Nicholas C | Oct 18 16
1 Answer

Concrete floor caulking is failing... why and how to fix?

My polished concrete floors are about a year old. Now I see that the caulking the contractor laid in the seams is starting to crack and split (see photo). The splitting appears to be occurring more often in the part of the floor that gets sunshine.

Anyone know why this is failing so soon? Was the wrong material and/or technique used? What is the fix? Thanks.

Port Townsend WA

Asked By Steve Hengeveld | Oct 21 16
12 Answers

Unventilated, highly insulated roof — replacing shingles

We are replacing the shingles on a cathedral roof.

The roof has been insulated from the inside. 8 inches of expanded polystyrene below the roof deck including cut and cobble between the rafters, and 4+ inches of additional eps and mineral wool below that.

The roof is not ventilated.

The shingles will be asphalt.

From what I have read, asphalt shingle roofs are not water or vapor permeable, so using a permeable underlayment will not provide a benefit, because vapor will still not be able to dry through the shingles.

Two questions.

Asked By Sharon Secrist | Oct 20 16
4 Answers

Replace fiberglass batts with cellulose or just add more insulation on top?

I have a great room attached off our main house in Central Massachusetts. I'm not sure what it is called, but its got normal walls for about 10 feet, then cathedral walls angled up for another 5, and then flat across the top for 10 feet or so. I'm pretty sure the room could use more insulation on the top, but I'm waffling on the best way to do it.

The Facts:

Asked By Bill Bertera | Oct 21 16
5 Answers

Garage and root cellar insulation

I received a call from my mechanical engineer today asking me how I planned to insulate the garage and root cellar ceilings. Both rooms are in the basement and above those ceilings are first floor living spaces. I told him my plan is to dense pack them with cellulose and probably add an inch of Polyiso covered with a layer of gypsum to break the thermal bridge and satisfy fire code. I was planning on insulating the rim joists with a couple of inches of ccSF on the inside, the only area in the house with the nasty stuff, mineral wool on the outside, and then dense pack would fill the bays.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 19 16
5 Answers

Taped Zipwall or sheathing with Ice & Water Shield on a REMOTE/PERSIST roof?

So any thoughts on what is better or more practical?

I'm getting ready to start sheathing a roof (which will have all of it's insulation outboard of the WRB and sheathing, with a cold roof on top). It is a R-66 EPS roof.

On one part of the project (a separate building, same construction technique (REMOTE/PERSIST), we used barnboard, then 1/4" plywood (to hide the ice & water shield above it) from showing through any knots or such from below (exposed cathedral ceiling), then R-66 of EPS above, with 2x4 furring and then plywood and then metal roof.

Asked By Brad Hardie | Oct 20 16
1 Answer

Zola window screen mounts... anyone found a fix?

While my Zola windows seem to be performing well (at the one year mark), the window screen mounts can only be described as "unusable". In fact they can damage the window seals and window surrounds when used as supplied by the manufacturer. So I'm looking for a workaround!

Is there a homeowner or window contractor out there with that's found a way to mount Zola screens without damaging the windows (see the issues list below)?

Thanks in advance for any leads or parts sources!

Port Townsend WA

Zola screen mounts have several design flaws:

Asked By Steve Hengeveld | Oct 21 16
6 Answers

Double backdraft damper needed for bathroom fan?

I am going to install Panasonic exhaust fans in our bathrooms in new construction through an unvented attic.. The Panasonic fan comes with a built-in damper and their installation guides mention using a wall cap with a damper too. This means there are two dampers.

The Panasonic damper is very light plastic does not seal well and opens easily. The wall cap damper is typically metal, making it a little harder to open. Our HVAC contractor suggests not using a damper at the wall cap but this worries me.

Is the best approach to use two dampers in line?

Thanks for your advice.

Asked By Jeremy Turner | Oct 19 16
14 Answers

can you create a blog on infrared heating panels?

People would benefit from knowing how infrared heating panels are more efficient, comfortable, and safer than conventional heating methods.

Asked By Iona Jonasson | Oct 19 16
5 Answers

Insulating over cedar siding with 1-inch rigid foam underneath

Hi All, Just purchased a home in northern Michigan. Built in 1988 with 1" of TUFF R(?) foam under vertically applied cedar 3" T&G. After inspection there are 2x4 stud walls, 3 1/2" fiberglass insulation,plywood sheathing, 1" TUFF R foam, 5/4 cedar siding, and no drainage opening. I was trying to add insulation to the exterior. Thinking about ROXUL board directly over the cedar, furring strips, and different siding. Any thoughts on this plan.

Asked By Bill Skaff | Oct 17 16
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