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2 Answers

Can you use a tank-less Heater to do both DHW and space heating (hot water baseboard)

We want to combine both DHW and space heating, as we have limited space

In Energy efficiency and durability | Asked By Joan Blood | May 4 14
1 Answer

What are the three most common mistakes with vapor retardars

what are the three most common mistakes with vapor retarders?

In General questions | Asked By Randy Nilsson | May 4 14
4 Answers

I will be adding a room to my house this summer and I am looking at a couple different wall configurations.

Any comments / suggestions / criticisms more than welcome.

Obviously these are not wildly original, they are based on so many great posts here and also on recommendations from BSC.


In Green building techniques | Asked By Greg Smith | May 1 14
3 Answers

What type of building envelope should I use on my resided house in Seattle?

We have a two story house in Seattle that was built in 1976. It has 2x4 exterior walls with R-11 rolled fiberglass insulation between the studs – has brown kraft paper vapor barrier on the inside of the house walls, has foil vapor barrier on the inside of the unheated garage; then on the studs is foil backed kraft paper, ¼” of white foam insulation board, then aluminum siding. It looks like they use slanted 1x4 bracing in the corners for shear bracing. There doesn’t appear to be any plywood on the exterior of the walls.

In Green building techniques | Asked By dale luhman | May 2 14
6 Answers

Triple-pane windows? Cathedral ceiling with Roxul? Minisplit? Affordability?

This might not be the forum for this long question, but, I'm driving myself a bit nuts with all the environmental/aesthetic/monetary values I'm trying to blend in designing and building our house. Maybe there are a few builder-psychologists willing to give council so as to arrive at a workable blend... and to quiet the competing voices bouncing around in my helmut.

In Green products and materials | Asked By Edward Krause | May 1 14
6 Answers

Is there a compatibility issue with Zip (Huber) R- Sheathing and open-cell Icynene?

While constructing a home in Eastern MA and utilizing 11/2" Zip R Sheathing on 2x6 walls, Icynene Open Cell foam was sprayed into the stud bay/wall cavity (against the Foam board backing). Shortly after spraying I checked a few spots to see the consistency of the foam and noticed that the foam had not adhered to the Zip foam board, creating a gap ranging in size from 1/4" to 2". There were a few locations where the foam had adhered, but the majority of the test spots revealed a gap as noted.

In Green products and materials | Asked By Jonathan Hahn | May 2 14
9 Answers

Slab on top of slab: Building science?

I have an existing foundation which is a trench poured monolithic pour, slab on grade with the perimeter foundation walls extending 40 inches to the frost line. It has perimeter stem walls extending 24 inches above the floor slab. The room is unheated, 400 square feet, used 9 months of the year. It has 9 foot walls and vaulted ceilings.

Architectural plans for the room call for the floor to be elevated 14 inches from the existing. The monolithic pour is uninsulated and has no poly in place under it.

In General questions | Asked By Dennis Dipswitch | Apr 29 14
13 Answers

I am thinking of using Huber’s new Zip System R-Sheathing on new construction

I have three questions:
1. What has been users' experiences with this product?
2. Do I need to install a rainscreen over it if I am installing fiber-cement siding?
3. What’s the best insulation in the 2X6 wall behind it? Is flash & batt overkill?

In Green building techniques | Asked By James Kuszaj | Apr 26 14
155 Answers

Serious Windows vs. Thermotech, Fibertec, Inline, Accurate Dorwin

Does anyone have experience with Serious Windows or Canadian fiberglass windows? I'm having a difficult time finding high SHGC windows (with a U-value less than or equal to 0.30) for my passive solar home that are affordable. Looks like the fiberglass windows can give me the performance I'm looking for, but I can't find any local installations to inspect the quality of manufacture.

In Energy efficiency and durability | Asked By Claire Anderson | Oct 1 09
5 Answers

Tightening up a 1949 mid-century modern

I just bought a really cool 1949 mid-century modern 2200 s.f. split-level home in the Chicago area (Zone 5) and will be doing a bit of work to it. The work to the exterior consists of all new siding - cement fiberboard and cedar siding set over the existing sheathing as a rain screen on 1x4 furring strips. I will be adding 1 1/4” extruded poly where the cement fiberboard is going, and for aesthetic reasons, adding 2” extruded poly where the cedar siding is going. I will cover the sheathing with the a WRB. New orientation specific Integrity Low E windows will be set as ‘outies’.

In Green building techniques | Asked By Nathan Kipnis | May 1 14
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