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1 Answer

KISS, exterior wall insulating plan?

Problem: My recently painted 1920's Craftsman in zone 5 has cedar lap siding over disintegrated asphalt paper over 3/4" lap sheathing, 2x4 studs, no insulation, LOTS of ventilation.

Plan: From the inside, fur out the walls 2", staple Tyvek against the inside of the sheathing and on studs, R21 Batting in bays then 1" XPS and 1/2" drywall onto studs. Simple right? Any foreseeable problems or alternatives with this?

In Green products and materials | Asked By James Anderson | Dec 17 13
11 Answers

Good idea for R-38 under a 2x4 shake roof?

I want to expand a top-floor bedroom to include an uninsulated 16’x9’ corner of my 1920s craftsman (zone 5). Its southwest exposure, 7/12 roof is cedar shingles on skip sheathing, across 2x4 rafters which bird-mouth onto the exterior wall exposing 2” of the backside of the frieze boards; exposed rafters outside, no vents.

In Energy efficiency and durability | Asked By James Anderson | Dec 16 13
2 Answers

Eric Werling’s Building Science Blues

Check out Eric Werling performing his original song, "Building Science Blues."

Thanks to Chris Laumer-Giddens, who posted the video here:

In General questions | Asked By Martin Holladay | Oct 16 13
7 Answers

Best practice for retrofitting insulation in a daylight basement

Hi all,

I've read quite a number of great articles here and on FHB about insulating basements. However, it seems most of the articles are targeting full height basements.

I have a project that differs a bit in that it is a daylight basement with a transition from concrete foundation to conventional 2x6 stud wall. I'd love to get some advice on whether folks here think my plan is reasonable and what the best practice might be. Additionally, it seems like there is some detail around the transition that might be hard to manage.

Previous system:

In Green building techniques | Asked By Keith H | Dec 16 13
1 Answer

Insulation Board on Sloped Roof

We are designing a home in Santa Fe, NM with a sloped roof. The structural engineer is really pushing back on the idea of using insulation board here because he doesn't know of a good rigid product to attach the metal roof to nor proper underlayment to use. Does anyone have a product recommendation or detail they could share to help us push for this? We'll use spray foam in the roof cavity, but our energy models suggest that the rigid board is going to make a big impact since it provides a thermal break.

In Green building techniques | Asked By Heather Gayle Holdridge | Dec 17 13
1 Answer

Best exterior veneer for very thick exterior foam sheathing

My wall plans for a new addition now call for 2x4 framing, OSB sheathing, rubberized adhesive membrane and 7 inches of Atlas R board poly iso insulation with 1x4 vertical furring. My original intent was to use metal siding by Firestone. A recent Building Science white paper on cladding attachment through exterior foam raised some potential long term issues with "heavy" siding over 6 inches of foam. My architect is currently recommending the use of light weight aluminum soffit sheathing as the siding. Has anyone done this before?

In Green building techniques | Asked By W. Timothy Ward | Dec 16 13
1 Answer

Doubled-studded walls & cold sheathing in WA

I live in western Washington state and I am designing a house and would like to incorporate some energy efficiencies in the design. I am mostly sold on double-studded walls however I do have reservations about cold sheathing. My builder is new to double-studded walls but willing to give it a go, as a result I am learning as much as can to help ask and inform as we move forward.

In Energy efficiency and durability | Asked By Michael Larrabee | Dec 16 13
15 Answers

Solar heat storage in sand bed under house slab?

Can anyone comment on the following technique? This is excerpted from a Breaktime post at http://forums.finehomebuilding.com/breaktime/energy-heating-insulation/p...

What you are thinking of doing is what we are already doing in the solar side of heating. I am building a solar heated house in st paul Mn using FOUR FEET of sand below the slab. This sand has it's own pex tubing for injecting the heat from the hot july and august sun, which will provide heat for the house through the new year!

In Green building techniques | Asked By David Meiland | Jul 11 10
4 Answers

How bad is MDG?

My builder installed MDG from TLC Mouldings. The specs call for MDF with
no added formaldehyde, but I did not remind him. Argh. How bad is
regular MDF? Should I rip it out, coat with an absorbent primer, move
to another country? My rater suggested heating the house to 80 degrees
for two weeks to cook the formaldehyde out. Thoughts?

In Green products and materials | Asked By Steve Knapp | Dec 10 13
30 Answers

Window condensation issue

I'm in the middle of constructing my home and have discovered a serious condensation / bulk water issue. First some background: We're in southern Maine. The envelope is a double 2x4 stud wall system 10.5" thick insulated with Roxul. Exterior air barrier is taped zipwall and interior air barrier is ADA with taped or gasketed seems and joints. No vapor barrier. We put in Intus Eforte UPVC windows.

In GBA Pro help | Asked By Brian Beaulieu | Dec 8 13
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