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6 Answers

Insulating 2x6 cathedral roof

Just read "How to Build an Insulated Cathedral Ceiling" trying to apply to my gut rehab project.
Zone 5a, house has a hip roof framed with 2x6. When I tore drywall off, found vented eaves with no venting on roof. Insulation was 6" fiber glass bats tGN#?with no air channel space. Roof has brand new shingles so I want to insulate from below. I am thinking non-vented roof, fill 2x6 void with closed cell foam and then install 2" foam on studs for thermal break. Does this sound like correct strategy? Should I install vapor barrier below foam board before drywall?


Asked By Steve Karkau | Oct 23 16
1 Answer

Insulate attic to prevent pipes from freezing

Long story short: We have pipes running through the attic of our garage to an addition. The pipes run close to the roof line and then go down an outside wall. The attic rafters are not insulated and the walls above the ceiling line are also not insulated. The floor of the attic where it goes over the house is insulated. The attic portion is open to the garage itself (its kind of like a crawl space), but the pipes will freeze at anything below 32 degrees, so clearly heat is not getting up to the attic from either the garage or the house.

Asked By Lindsey Carden | Oct 24 16
3 Answers

Cathedral ceiling insulation

A quick clarification needed to settle my mind, I am hoping I solved my condensation problem. I am redoing my leaking cathedral ceiling which had R30 Roxul, no vents and tongue and groove pine. I am in northern VT and as you can imagine I was getting condensation on the underside of my roof deck.

Asked By John Hunt | Oct 24 16
3 Answers

How much insulation for a steel beam?

How much insulation do I need over a steel beam to stay above the dew point inside the house?

This is new construction in progress, in NC. The I beam is over a door and window assembly and contained within the wall, sandwiched between the sheathing and drywall. However, no consideration was given to insulating it in the design.

Asked By Jeremy Turner | Oct 22 16
0 Answers

water furnace 7 series desuperheater

So i am in the process of having installed 3 water furnace 7 series with desuperheaters. Trying to figure out hot water options. Main side of the house, Im thinking a marathon storage tank heated from the desuperheater. This would feed a 80 gallon heat pump water heater.

Asked By dean sandbo | Oct 23 16
2 Answers

Siding with a step

I have an addition that I have added to my home and am now in the process of finishing up the furring for the rain screen and getting ready to install siding.

The issue I've run into is that I am using vinyl siding to match the original house, but the addition has a basement and the main portion is slab on grade. Because of this, the addition has a rim board that extends roughly 12" below the original slab/sill plate line.

When I go to install vinyl siding the starter strip on the old portion will not line up with the addition.

Asked By Mike M | Oct 22 16
4 Answers

Zone 3 minimum wall assembly

New construction proposed 2x4 wall assembly.
Latex paint, 1/2" Sheetrock, BIB fiberglass, OSB, Tyvek wb,1" gap, stone or smart siding.
Doesn't this just meet the minimum requirements in Zone 3?

Asked By Mike Beckham | Oct 22 16
4 Answers

Zone 3 roof dampening concern unvented attic

New home construction - roof design
asphalt shingle, 30# felt, OSB, 5 1/2" open cell foam. Should I be concerned about the design causing moisture problems over time?


Asked By Mike Beckham | Oct 22 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
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