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3 Answers

Sure, exterior rigid foam when blowing wall cavities might be a good idea, but is it NECESSARY?

My 1920 platform framed home is on the border of climate zone 5&6.

The empty wall cavities are framed with true 2x4s, 16 OC. Walls are covered with lathe and horsehair plaster on the inside and 1" pine sheathing boards outside. The current siding is a horrendous installation of vinyl over the original clapboards. The cavities are now empty.

We intend to remove the vinyl (carefully, for reuse), strip the clap boards, dense pack the wall cavities, wrap the house in tar paper, and rehang the vinyl.

In Energy efficiency and durability | Asked By Mark | Oct 5 15
7 Answers

Limited soffit venting clearance for baffles + insulation

Just installed a new roof with Maximum Ventilation exhausts and removed old fiberglass batts. I was originally planning to do the standard R50 fiberglass blow-in and soffit baffles. However, I discovered that in this 1960's back-split, the roof is quite shallow and rests directly on the double brick wall so there is only 3-4" clearance for soffit venting, leaving only 1-2" left for insulation under the baffles around the perimeter. This seems like a recipe for cold spots.

Some options:
1. Just proceed as planned; hopefully cold spots won't cause condensation on the ceiling.

In General questions | Asked By Deb N | Oct 8 15
6 Answers

Vapor barrier in attic?


In Energy efficiency and durability | Asked By Lucy | Oct 4 15
1 Answer

EPA-approved wood stove with sealed-combustion design?

I'm working on a retrofit that mandates that any wood stove must be EPA approved as well as have dedicated combustion air. I have had trouble sourcing a wood stove with a dedicated combustion air inlet . Is anyone aware of a product with this feature?

In Green products and materials | Asked By John Kidda | Oct 8 15
14 Answers

HVAC selection help

My new house is under construction and I need to finalize my HVAC system soon. Some details:

Zone 4, 3800 sq feet (About 1900 first floor, 1550 second floor, 350 room over the garage), crawl space (conditioned), open web floor trusses for second floor.

I had the manual J load calc reviewed by an engineer and have sent it back for some corrections (there is better insulation than is shown and better air sealing, and a couple other things which will lower the load. He didn't add the ventilation load though, which will raise it), but as it stands right now:

In Mechanicals | Asked By Michael Geoghegan | Oct 7 15
4 Answers

Struggling with how to use foam on walkout over Canadian shield zone 7

I'm building a walkout basement (1000 sq ft) in zone 7 (NW Ontario Canada) and have purchased 1000 sq ft EPS at 5 inches and 1000 sq ft at 1 1/2" XPS (I was told its much better to use above the XPS since its much more rigid when walking on during the pour)..
I am struggling on how to best use the foam on the walkout side (I got a great deal so I have lots of EPS and XPS)..

In Green building techniques | Asked By tim brown | Aug 18 15
8 Answers

What are your thoughts about studs left un-drywalled?

I saw photos on Houzz of exposed interior wall studs - Prentice Architects and HS2 Architecture.
What are your thoughts? The light is attractive. What are your thoughts?

In GBA Pro help | Asked By Mary Schwaba | Sep 29 15
1 Answer

What is best insulation process for an addition?

We have a mobile home built 2007. We are adding an addition on the north side, 14 feet out, 70 feet long. Do we use 6 inch walls or regular 3 inch walls? With what type of insulation? We live in southern Illinois where it can get below zero. Also, will we need another heating source? Furnace is all electric, Vexar by York. We are trying to keep this affordable to heat and cool efficiently.

In Energy efficiency and durability | Asked By Victoria Harmon | Sep 30 15
9 Answers

Antique house #1: Cedar Roof

I will likely be taking on a crazy project in the next few months - buying an old house in Rhode Island, and improving it, on speculation.

The general scheme is to
--Do minimal work on the older (about 325 years) portion of the house,
--Expand/rebuild the newer (about 115 years) section with modern kitchen, baths, windows, etc.
-- Remove ugly garage, breezeway, and dormer.

In General questions | Asked By curtis betts | Sep 30 15
1 Answer

Is R-13 x 2 greater than R-21 (for a 2x6 wall)?

Two layers of R13 batt insulation is cheaper than one layer of R21 batt (for a 2x6 wall). Can I place 2 layers of R13 in the wall and achieve a greater R value than one layer of R21?

One other note: Unfortunately the R13 is faced. Would two faced layers cause a problem?

Location-Southern California-92705

In Energy efficiency and durability | Asked By Keith Messick | Oct 8 15
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