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2 Answers

Crawl space retrofit: three zones, low clearance

We are pursuing a remodel of a 2-story house in climate zone 3, coastal California. The first floor was built around 1920, and the second floor was added in 1980.

In addition to changing interior layouts, we are trying to make it "tight, well insulated, and mechanically ventilated", with a primary goal of higher IAQ due to dust/mold sensitivity. Thermal comfort is important too, but the climate is pretty mild.

Asked By user-6772204 | Feb 28 17
13 Answers

Your thoughts on my window choice

Thoughts on window/glass choice. Climate Zone 4/5 on the line.

All are Casement with one Awning. (16) windows all together

Full Frame Center Glass
U .15 U.07
R 6.7 R 13.5
SHGC .22 SHGC .31
VT .33 VT .50

Please let me know what you think of this choice for general all round useage. We aren't chasing passive solar heating and we aren't building a Passive House, Goal is 1.0 ACH


Asked By Amy Miller | Feb 28 17
4 Answers

Ceramic tiles over rigid foam

I have a large room with concrete slab floor and would like to insulate it and place finished flooring materials over it. I believe 1/2" plywood over the 1" rigid foam will support hardwood flooring. However there is a portion at the entryway that I would like to cover with ceramic tiles. Is the 1/2" adequate underlay going to be sufficient? if not what can I use to insulate plus finish this portion with ceramic tiles and match the height of the (1" foam, 1/2" plywood and 3/4" solid hardwood flooring?)

Asked By kingfisher224 | Feb 28 17
1 Answer

Double stud house plans

I am looking to build a roughly 1600 square foot single story home on a slab foundation in New Hampshire. My goals in mind are to build an energy efficient, well insulated home and have looked into different techniques to achieve high (>40) R values for walls and think that double stud framing would be the most cost effective way to go about this.

Asked By user-6777547 | Mar 1 17
1 Answer


i am trying to understand the design, or expected infiltration, after a house passes a 3ach50
blower door test
can result be used to determine a seasonal infiltration rate for the house to see if
additional ventilation or combustion air is needed for equipment
how do you understand impact of household appliances ie dryer, bathroom exhaust fan, kitchen hood

Asked By Kevin Mick | Mar 1 17
7 Answers

Ultra-Aire XT105H vs. Honeywell DR90A2000

I've seen much praise of the highly efficient (most efficient?) UA XT105H whole-home dehumidifier in my research. It certainly seems like a winner. As with many things, though, having the best often comes at a price and the XT105H seems to be no exception to that rule. See below for the specs:


Asked By Lance Peters | Feb 28 17
1 Answer

Vented Attic Vapor Retarder

Getting confused in my research today, looking for feedback.

Climate Zone 5, Vented Attic with Blown-In Fiberglass.

Is it correct, vapor retarders are not required in climate zones other than climate zones 6 or higher for vented attic assemblies?

Asked By Bridget Lamberson | Feb 28 17
4 Answers

Exterior electrical outlets with exterior insulation

I am at a loss how to install and connect the electrical outlets on the exterior of our new build. We are installing 2.5" of mineral wool insulation with 1x4 rainscreen furring and fiber cement siding. None of the electrical boxes (e.g., Arlington) are deep enough to span this much insulation, and I understand that I can not run NM-B through the insulation to a box mounted to the furring. How is everybody else doing this?


Asked By Robert Heinse | Feb 28 17
20 Answers

Follow up question re: basement subfloor (climate zone 7a)

A couple of weeks ago I asked a variety of questions pertaining to my livable space basement retrofit for a 1974 home in climate zone 7a. Recap: there is no exterior foundation or under slab insulation, etc. No water penetration issues into the interior but part of the basement has shown recurring efflorescence and some spalling in a few places.

Asked By user-6759891 | Feb 24 17
3 Answers

Basement finish - existing exterior R-5 - questions on interior insulation

I am finishing my basement in Minnesota. It is a walkout design. The walkout portion of the wall is a 2x6 wall with typical fiberglass bats and poly on the interior. All rim joists have 2" of foam spray.

My exterior concrete walls are covered with R-5 foam board protected with a thin layer of sand/rock pebbles.

I have been told and read so many ways to finish my interior insulation that I am dizzy. I have been told:
- No insulation, R-5 on exterior good enough.
- Put poly on concrete and get R-15 Kraft faced insulation between studs
- No poly at all, R-15 between studs

Asked By ZDude | Feb 28 17
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