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5 Answers

Attic insulation advice/feedback

We recently moved into a 1952 Cape Cod home and will be remodeling the entire 2nd floor attic/living space so now is the time to get the insulation done right. As a result, I have been doing considerable reading on the topic of insulation and would greatly appreciate some advice on my current plan to “cathedralize” and insulate this space.

The plan:
Vent the soffits.
Create a 1 inch deep soffit to ridge ventilation channel in each rafter bay using .5 inch rigid XPS foam board sealed in place with caulk/spray foam.

In General questions | Asked By Chris Kolloff | Mar 18 15
1 Answer


Has anyone seen any study on the relative energy costs and savings of sun tubes? I have a client interested in one of these and I'm not sure if it's a good idea in general.


In Energy efficiency and durability | Asked By Dan Kolbert | Mar 19 15
1 Answer

How do I integrate rainscreen at soffit?

I'm installing a rainscreen (1x4 battens) over 3" of polyiso foam and 3/8" plywood. I'm in Northern CA, zone 3B. My WRB will be Tyvek wrap over the foam. I understand how to terminate and vent the rainscreen at the bottom of my wall, but am not sure what this rainscreen should do at an arched soffit above my door opening.

Attached are a photo of the framed soffit above the door, before installing the rigid insulation. Also is a photo of this detail sketched out.

In Green building techniques | Asked By Dan Burgoyne | Mar 19 15
12 Answers

I live in a basement apartment — The landlord installed insulation (crawl space) giving off a chemical odor

Hi. My landlord installed insulation today behind the walls of my living area. It is giving off an intense chemical smell... Is it safe for my son and I to be ingesting it while we sleep? He was coughing a lot before bed and it made me dizzy.

In General questions | Asked By Caren Donatelli | Mar 18 15
8 Answers

Double vs triple paned on this window quote

Hi all!
I'm wondering if the performance of an identical window moving from double to triple paned will make up for the price difference in the long term (I suspect it will).
Our quote from one company for all windows (Vinyl, Energy Star Rated) is $21k for our new build.
The upcharge to move from double to triple for all windows and doors (fixed and operating) is $1700+tax. Canadian pricing and Zone 7 build.
Would you do it? It seems reasonable to me. I'll attach the quote with window list here in pdf form (hopefully this is kosher).
Thanks in advance for your insight!

In Energy efficiency and durability | Asked By Nik Fiorito | Mar 17 15
9 Answers

DVHP on Southern Maine Coast

We are building a new home: 2,200 s.f., three floors living, southern exposure, closed-cell foam, R-40 and R-60 +-, radiant heat (I know, my wife insists), HRV, little propane stove.

We are seriously considering an AirGenerate ATI66 for hot water.

Here's my thinking:
Summer, run a supply duct from second floor, exhaust to first floor living area;
Winter, supply and exhaust from outside;
Shoulders, supply and exhaust from outside.

In Mechanicals | Asked By Peter Whitman | Mar 18 15
4 Answers

Duxton Windows

Has anybody used Duxton windows. We are interested in a very energy efficient window for a new home we are preparing to build. We are leaning toward Intus but I think I should consider a quality North American product. The windows we are considering are casements with simulated divided lights. I would prefer no maintenance on the exterior and thinking we could go with painted wood on the interior. Any thoughts/ideas/opinions would be appreciated.

In Energy efficiency and durability | Asked By william dempsey | Mar 19 15
1 Answer

Attaching plastic attic baffles together

I purchased a bunch of ADO ProVent 14 inch plastic attic baffles.

I'm retro fitting them in between the insulation and roof in a cathedral type setup in a bungalow. So, I need to attach 2 or even 3 together before sliding them in.

I'm thinking of using Tyvek Housewrap 2inch tape, either on one side or both of the attic baffles to attach them to each other before sliding them in place.

I'm open to other products to attach them to each other. Any advice?

In Green building techniques | Asked By Jeremy M | Mar 19 15
2 Answers

Is fiberboard air impermeable?

A recent GBA post noted that some builders are finding that OSB isn't always air impermeable. I'd like to know if fiberboard, such as Biltrite or BraceRite, is air impermeable. Specifically, I'm interested in trying to use it as an air barrier, in an assembly where I need the sheathing to be able to dry, and fiberboard has a permeability of around 20. But can it be an air barrier, if I tape or otherwise seal the seams? I can't find this info on the company's website or anywhere else I've been looking.

In GBA Pro help | Asked By Rachel Wagner | Mar 19 15
1 Answer

What is the layering sequence when installing a slab on grade?

Moisture barrier, rigid insulation?

In Energy efficiency and durability | Asked By Robert Marrapodi | Mar 18 15
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