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19 Answers

Insulating floor of mudroom before closing it off

I'm building 5' by 8' mudroom addition where there previously had been a dilapidated porch-like structure. I've poured the foundation and secured the sill. The concrete foundation is about 5 inches above soil, then 6 x 6 sill. I will be framing the floor with 2x 6. I'm stuck with these dimensions because of grade etc. This "crawl space" is NOT connected the the main house's crawl space and will be 100% inaccessible once the subfloor goes down. Also, foundation is non vented.
Anyway- the plan is to-

In General questions | Asked By Joseph Moore | Apr 29 16
1 Answer

Synthetic underlayment

I have read many posts and articles and believe I know the answer to this question but would just like some confirmation. I am building a cathedral ceiling, vented under the sheathing, and using 24 ga galvalume R panel fastened directly to the sheathing. Since I live in a warm climate, I don't think I should use asphalt felt due to the potential for it to adhere to the metal roof. Does it matter if the synthetic underlayment is breathable since I am venting under the sheathing and if so, what are some recommended products for this use?

In Green building techniques | Asked By Scott Smith | May 18 16
16 Answers

How can one adjust the temperature on an indirect heater?

I recently moved to the NE from the west coast and have no experience with these things, but my client has water that barely reaches uncomfortably warm, even at a bathroom 10' from the tank. The output pipe on the tank is also easy to grab and hold, while the pipes bringing heat to the tank are momentary-contact only.

What I see looks like someone has plumbed the tank as one of the three zones of baseboard heat.


In Energy efficiency and durability | Asked By Skip Harris | May 16 16
4 Answers

Clear 6-mil polyethylene vs. 10-mil proprietary sheeting

In most of the correspondence at this site, I see clear 6-mil poly being used and recommended as an under slab vapor barrier. There is a proprietary brand of 10 mil polyolefin which makes a claim, which is that the alkali from concrete degrades "ordinary" poly over time which leads to the breakdown of the poly and hence the vapor barrier. Their pitch is of course that you only get one chance to get that sub-slab vapor barrier right and that you should use their product.
Is that advertising hyperbole or is that alkali degradation something which which we should be concerned?

In Energy efficiency and durability | Asked By Ted Cummings | May 17 16
6 Answers

Luxury vinyl tile / plank

We need to select our flooring. Our plan had been to use wood laminate, but several people we know have recommended that we look into luxury vinyl. We hear that it looks very similar to wood or tile, is much easier to care for than wood, and is much cheaper than tile. Do people on this forum have experience with and/or opinions about this type of flooring?

In Green products and materials | Asked By Reid Baldwin | May 3 16
32 Answers

Unvented 5/12 pitch slate roof built with Zip sheathing and closed-cell spray foam insulation

I am Homeowner building house in Port Washington , NY, ( Long Island )
My Architect will try to go for passive house certification , so "She" needs to be air tight and super insulated .
"She " will have ERV system and attic floor will not have any insulation , so temperature will be balanced throughout interior of the house
Exterior walls is constructed with 3/4" zip sheathing over 5-1/2" LSL Versa studs ,
Interior cavity of wall studs will be 3" of closed cell spray foam and balance of 2-1/2" will be open cell spray foam

In Energy efficiency and durability | Asked By Joe B | May 15 16
5 Answers

EPA study finds induction cooktops to be no more energy efficient than regular electric cooktops

I was reading this review: http://thesweethome.com/reviews/best-portable-induction-cooktop/ and it mentioned this study from the EPA in 2014: https://www.gpo.gov/fdsys/pkg/FR-2014-12-03/pdf/2014-28212.pdf

It appears that induction is right around the same efficiency level of regular electric cooktops. This also calls into question the frequent claim of induction giving off less waste heat -- that would be impossible, if it's no more efficient.

This would remove induction from the list of energy efficient technologies, and relegate it to basically a luxury/convenience.

In Energy efficiency and durability | Asked By Nick Welch | May 17 16
4 Answers

Adding insulation to stucco wall in Los Angeles area home

I'm retrofitting a home near Pasadena, CA and am beginning to look at options for insulating the currently-uninsulated exterior walls and could use some advice. The home was built in 1963, and the wall assembly appears to just be stucco on lath, then building paper, then studs, then drywall. There's no sheathing and no lateral bracing except for some diagonal 2x4s at the corners. (please see photos)

In GBA Pro help | Asked By Chris Stratton | May 17 16
11 Answers

Revisiting a wall in Climate Zone 5A

Construction is on the horizon in our "pretty good house" in Iowa, Climate zone 5A.

Although I know our wall isn't perfect, we have chosen the materials for a variety of reasons. Currently from exterior to interior we have:
-Hardi-plank siding
-1x4 furring strips for rain screen
-Tyvek WRB
-2" rigid insulation, currently XPS
-Sheathing, currently OSB, taped
-2x6 framing, open cell spray foam in cavity
-drywall, with latex paint

My questions after reading and re-reading the prevailing thoughts on this site are:

In Green building techniques | Asked By Thomas R | May 10 16
1 Answer

What should be done to replace siding but leave window?

The original windows on this project were attached to the building by face nailing through an integral brick-mold. The windows were subsequently replaced with "replacement" windows, which left the existing window frame and brick-mold in place. The brick mold was wrapped in coil stock and fastened with nails along the edge of the brick mold perpendicular to the sheathing. The facilities manger wants to replace the existing ugly and degraded siding with a quality vinyl.

In General questions | Asked By josef chalat | May 17 16
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