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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:
Wall:

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
2 Answers

Wall assembly with XPS foam and stucco

I am looking for help with my exterior wall assembly. This is for a house with Stucco exterior and XPS foam. We are building a house in Climate Zone 3 (SF Bay Area). Required wall insulation here is R13, but I would like to do better and add 1 inch XPS foam to increase R value and eliminate thermal bridging.

I am confused about the appropriate wall assembly after reading several articles on GBA and other sites. Code requires "2 layers of Grade D building paper" over the OSB/Plywood.

Here are two wall assembly options I have in mind:

Option A:
1. Drywall

In GBA Pro help | Asked By Thomas Schulz | Dec 15 13
5 Answers

Are cupolas worth considering on a well insulated home for ventilation?

Are cupolas worth considering on a well insulated home for ventilation in the summer? In zone 5a there are some months where the day time requires some A/C and the night does not. A whole-house exchange of air would be nice around 8 o'clock at night, when the temps outside drop.

The idea would be to open up the cupola along with the first floor windows and allow the stack effect to exhaust the air. I guess it's the same idea as the whole house fan that pulls all the air out of the house and into the attic. We had one in our old house and it never seemed to work as good as the theory.

In Mechanicals | Asked By russell berenson | Dec 9 13
12 Answers

Insulating exposed rim joists

We are building a home in Maine where the basement won't be finished for some time. Besides loose fill insulation, what can I use on the rim joists that is fire resistant when left exposed.

In Energy efficiency and durability | Asked By tom ruben | Dec 14 13
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