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4 Answers

Water-resistant insulation

We are rebuilding many small buildings (Not Houses) that were flood damaged by Hurricane Irma and have a small probability of flooding again. They are 2"x4" framed walls, sheathed with 1/2" plywood, covered with #15 building paper or house wrap and sided with vinyl or cement board. Remediation work included removing all wet drywall and fiberglass insulation, cleaning and disinfecting the wall cavity, and drying the framing lumber and sheathing to a moisture content of 8% or less.

In Energy efficiency and durability | Asked By Anthony Swoope | Feb 14 18
4 Answers

LSL Framing

I'm planning on building a small cabin with some laminated strand lumber (LSL) framing. I'll be doing 24 inch on center, so I'm going with LSLs for some additional strength. Straighter walls and easier installation are added benefits too. LSL lumber is very expensive, so I'd like to just use them for the studs and then use standard dimensional lumber for top and bottom plates. I'm trying to find a cost effective way to incorporate some of the benefits of LSLs. I'm thinking that warping is less of a concern for the top and bottom plates.

Is there any concerns with this approach?

In Building Code Questions | Asked By Rodrob15 | Feb 14 18
22 Answers

How does someone cancel subscription when there seems to be no way out??

Could someone guide me in the cancellation of membership? it doesn't seem like it is possible to do so.

Thank you

In General questions | Asked By James Someone | May 27 17
9 Answers

Fastening details - deck ledger to insulated slab

I am designing an insulated Monolithic Slab. I plan to install 4" of Roxul comfort board beneath and around the perimeter of the slab.

Does anyone have experience attaching a deck ledger to a slab (or stem wall) that is insulated with Roxul? Or is it advisable to place a higher density product beneath the ledger to avoid compression which may happen with the Roxul Comfortboard?

What type of fasteners are recommended for this application? Would a standard wedge type concrete fastener like a red head work?

Other solutions?

In Green building techniques | Asked By Michael Iacona | May 19 16
10 Answers

Heat pump water heater selection

My house is all electric in southern California and I plan to replace my electric water heater with a heat pump water heater. The plumbing professionals have little to no experience with these and are basically asking me to pick the water heater and they'll install it. From the research I've done it looks like the best choices include the Stiebel Eltron Accelera 300E and the Rheem Performance Platinum 80 gal. The Rheem is currenly on sale for $1600 at HD while the best price I saw for the Accelera is $2400. I believe my utility has a $250 rebate for the Rheem.

In Green products and materials | Asked By user-7014439 | Feb 11 18
31 Answers

Using hydronic in-floor heat in a superinsulated earth-bermed house

I'm planning an earth-bermed house at the 4,000 foot elevation in the mountains of eastern Washington. it will be single story, 8 foot 6" or 8" ICF walls on the sides and back. Back fill to 6" from the top of the wall.
The front will have a double 4" ICF front wall 2' tall and then double framed walls with thermal break to the top. This is south facing. front wall insulation is cellulose at about 18" thick but mostly windows 140 sq.ft on a 340 sq. ft. wall.
The floor will be 2" or 4" insulation with 4" concrete floor.

In Energy efficiency and durability | Asked By Grissom | Feb 13 18
13 Answers


We have a new construction home, less than one year old. Windows are the type that slide inward to clean, etc, vinyl, double pane. We have had temps drop below zero a few days in the past couple weeks. Whenever it gets below 0 degrees, we get condensation. Not the entire window, but along the bottom edge of the interior window, the space in between the bottom fixed window and the top slider, and in just a few windows it will frost in the bottom corner of the frame. Have checked humidty, and we run about 25%. Also have a call into the window rep, but haven’t heard back yet.

In Energy efficiency and durability | Asked By Kathleen J | Jan 2 18
2 Answers

Application of 2/3-1/3 rule when rigid foam is vapor barrier

I submitted a question a couple of weeks ago: "Rigid Foam Between Walls" in response to which I received numerous very helpful answers. Thanks again.

In General questions | Asked By David Williams | Feb 14 18
3 Answers

Bungalow porch: Should we insulate the ceiling?

We are building a Craftsman Bungalow in Farmington, Maine and the house has hip roofs and an open front porch. The porch roof is integral with the main house as it is shown in the attached figure.

My question is: Should the porch ceiling be insulated with a vapor barrier like the interior ceilings? We are planning on using Roxul insulation with a vapor barrier in the main house to get us an R-50 rating.



In General questions | Asked By User-6980234 | Feb 14 18
1 Answer

Whole-house fan in cathedral ceiling design

I'm building in climate zone 6B and I'm trying really hard not to put in AC. Our house is at 7000ft but we still get a few weeks of hot temperatures that are bearable during the day but are too hot for us to sleep at night. My thought was to do an air flush in the evening using a whole house fan.

In Mechanicals | Asked By Steve Mackay | Feb 13 18
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