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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.

In General 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:

In General questions | Asked By Bill Bertera | Oct 21 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.

In General questions | 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:

In Green products and materials | Asked By Steve Hengeveld | Oct 21 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.

In Energy efficiency and durability | Asked By Bill Skaff | Oct 17 16
3 Answers

What's the best all around roofing/insulation solution for Zone 5?

Hello to the community. I am in northern Nevada zone 5. This is an arid valley with normally low humidity but it can get some really high winds... upwards of 80 mph. The house I just bought was built in the 70's. There is about 6 inches of blown insulation in the attic but none under the roof sheathing. I do plan on bringing the attic insulation up to at least R40. The attic has two small gable vents but zero soffit vents. The roof is completely failed cedar shakes with a lot of exposed sheathing throughout.

In Green building techniques | Asked By Roger Smith | Oct 20 16
9 Answers

What's the best way to renovate/rebuild an old south-facing exterior wall?

Hi All - I am a newbie to this group but have considerable building experience remodeling and renovating homes, and completing unfinished properties. Still, I am no expert building contractor.

In Energy efficiency and durability | Asked By Roger Smith | Oct 2 16
2 Answers

2016 heat-pump water heater rebates - Opinions on best heaters?


There is a $750 Massachusetts rebate on air source water heaters. There are a lot too choose from. Any opinion on which one would be the best choice for a small 2 bathroom?

Thanks for any input.


In Green products and materials | Asked By Seth Capista | Oct 18 16
2 Answers

Attic insulation

I'm curious if anyone has any advice with concern to insulating an attic that contains a gas furnace (sealed combustion)? The unit is placed pretty close to the rafters- about 8"- and the attic is only about 5' at the ridge. Is it best to create a conditioned space for the unit or the whole attic? I'm new to all of this, so I'm not sure what to watch out for. Any advice would be appreciated. Also, does anyone have any recommendations for insulation contractors in the Boston area?

In General questions | Asked By Jeff Cannon | Oct 15 16
13 Answers

High Performance Home definition in as few words as possible.

I would like to see something less than an elevator pitch that gets to the route of what a high performance home is for the average potential new home client. Everything is too wordy and goes into air sealing, superinsulation and the why and the how - too much eyes-glazing-over detail. We need more of a slogan in this business. I'm putting it out there as a problem to work on. 140 characters perhaps?

In General questions | Asked By Robert Swinburne | Oct 17 16
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