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5 Answers

Advice on water heaters and air sealing

I am building a two-story house, 24 X 40'. The 1st floor is below grade on 2 sides (poured concrete with 3" of Roxul below grade and 4.5" covering any above grade concrete)) and exposed to the south and east . All walls above grade are 2 X 6 sheathed with 1/2" CDX (semi-advanced framing using double top plates) to be filled with cellulose and covered with 3" of Roxul. The roof is to be made with 2' heel trusses to allow 2' of blown cellulose insulation.

In General questions | Asked By Brad Abernethy | Aug 15 13
12 Answers

I need help insulating a kneewall

Hello All.

I recently had an energy audit done, and, not surprisingly, big issues were found with the knee walls on the second floor. This is a "contemporary" Cape in Massachusetts.

I'm in the middle of rectifying the problems. Here is a description of the issues.

In Energy efficiency and durability | Asked By Alex Jones | Mar 10 13
2 Answers

We are replacing our fixed-lite windows with laminated IGUs for noise reduction purposes

We are replacing our fixed lite windows with laminated IGU for noise reduction purposes. We can accommodate a 1" width. What is the best configuration to use? We are considering (1) 1/4" monolithic / 1/2" airspace / 1/4" laminate (.03" laminate) or (2) same configuration with two lami and a 1/2" air space.

In Energy efficiency and durability | Asked By William Naylor | Aug 20 13
4 Answers

2x6 wall with spray foam and rigid foam

While searching the net for some ideas on building a warmer wall, I came across this design. Had originally planned to go with double 2x4 wall.

Can you see any problems with this kind of wall? I plan on using spruce clapboard, strapping for rainscreen and building wrap. All on 16 centers.

I know the foam spray is supposed to be airtight, but I’m not really 100% sure of that. So would it be a good idea or just a waste of money to add some sheets of plywood on the inner side of the 2 inch foam board to make an airtight unit?

In Energy efficiency and durability | Asked By paul fowler | Aug 19 13
6 Answers

Where to find off the-shelf green house plans?

I am glad to pay an off-the-shelf price for the plan. I have an accepted contract for a lot, now I have a short deadline to get a lot-specific house plan-materials list-cost breakdown to the bank providing the loan. Bank wants stick-built. The view is primarily East, secondarily North, which complicates things. I really want to build green. Can anyone help with this request?

In General questions | Asked By Michelle Busbee | Aug 18 13
6 Answers

Is the use of rigid foam on both sides of OSB an issue for moisture avoidance?

I am about to start construction on a new residential house in Seattle (3-Marine).

Would the following wall construction (from outside to inside) create any issues?

3/4 furring strips for rainscreen
2 inch R-Max Thermasheat 3 - aluminum foiled
2x6 wood wall construction with following insulation between studs
- 2 inch R-Max Termasheat 3 - aluminum foiled
- 3.5 inch batt insulation unfaced

In Green building techniques | Asked By Joerg Zender | Aug 19 13
5 Answers

Insulating a brick wall? I cut it open to find only 2" of space between wood panel and brick...

Question: I have a house built in the mid 60s . I just cut open the back split walls and found the lack of insulation in our brick exterior walls. There were days when the room was freezing so I want to add some insulation without hurting the bricks. Currently the layers from out to in are bricks -- building felt- 1" furring - 5 ply paper-wood "stuff"- 1" furring. The furrings are 18" apart. Should I remove the everything to the bare brick, redo furrings and use the 2" foam insulation for R-10 or do I have to leave space for air?

In Energy efficiency and durability | Asked By Josh Raine | Aug 16 13
5 Answers

Do the usual minimum thicknesses apply to "R-Sheathing" products?

Huber and RMax and maybe others offer insulated sheathing - OSB and polyiso fused together with the OSB on the outside. When building a wall assembly with this, do you have to follow the minimum thickness guidelines here:


even though the OSBis on the outside of the envelope and will be able to dry to the outside? Specifically, I'm wondering about a 1.5" R5 insulated sheathing on a 2x6 wall in Southern Maine (Climate Zone 6, but close to 5).

In Energy efficiency and durability | Asked By Cy Kilbourn | Aug 17 13
6 Answers

A New York Times article on the Passivhaus standard

The latest New York Times article on the Passivhaus standard is called "The Passive House: Sealed for Freshness."

The article quotes Katrin Klingenberg, and interviews Don Freas, the owner of the Freas house that I described in one of my blogs, More Passivhaus Site Visits in Washington State.

The article also mentions GBA and the Pretty Good House. So check it out.

In PassivHaus | Asked By Martin Holladay | Aug 14 13
0 Answers

Looking for a good contractor in the Seattle area for building a "berm"-style house

A N.W. area contractor familiar with "berm" home type construction. Probably cement. Referrals please.

In General questions | Asked By Mr.Kim Paisley | Aug 19 13
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