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3 Answers

How to attach mineral wool to crawl space walls?


I'm building an addition, currently insulating the crawl space walls, but I'm unsure how to affix mineral wool insulation to complete the job.

The concrete floor was poured over 3" of XPS, and I installed (prior to the pour) poly over the XPS and up the walls and lapped over the top of the foundation.

I installed 3" XPS in the joist bays, and 3" XPS on the concrete wall, adhered to the poly with adhesive caulk. I sprayed foam around the XPS to seal the assembly.

I want to add a layer of 3.5" Roxul mineral wool, both for the added R factor and as a fire barrier.

In Energy efficiency and durability | Asked By Jeffrey Clewley | Mar 22 16
1 Answer

Henry Blueshield housewrap

I am going to be stripping and residing my house with vinyl. I was looking at this product for air sealing the exterior walls -- or is taping the OSB seams just as effective?

In Energy efficiency and durability | Asked By David Bernard | Mar 22 16
1 Answer

New Kumo Cloud for Mitsubishi Mini Split

is anybody using the new Kumo Cloud / app ?


I have read here that for some, the temp control /performance was improved when using the remote thermostat, MHK 1 , which was also a part of the honeywell gateway system



will the kumo app work with the MHK1?


In Mechanicals | Asked By p Ha | Mar 22 16
3 Answers

Metal building with block stem wall/block ground floor not smart?

I'd like to build a stem wall or ground floor of blocks for a metal building. However, I was told by a metal building supplier that the company doesn't recommend a metal/block hybrid or basically putting a metal roof on a block wall! My stab is sway, especially in hurricane areas. My question is how to tie a decent stem wall to a metal building without sacrificing trees?

In General questions | Asked By Chris Roso | Mar 21 16
9 Answers

Planning to construct a certified PassivHaus just north of Toronto, Ontario, Canada.

Currently live in a 2 storey ICF house with a full basement that I built 16 years ago. Really believe that ICF is the only way to build. After doing some research, I haven't found any passive houses that have been built with an ICF building envelope. Almost all houses have been built with various wood framing systems combined with cellulose or other insulation products. Is there a problem with an ICF building envelope?

Thanks in advance,

Andy Voura

In PassivHaus | Asked By Andreas Voura | Mar 17 16
2 Answers

Underlayment on a low-sloped metal roof?

Our roof deck is 15 yr old Techshield and the slope is 3.4 and 4.2. We are having old asphalt shingles removed (thanks to hail storm) and new standing seam crimped style 24 guage metal roof installed. Live in Texas and occasionally get ice. All of the 5,000 sq.ft. house drains into 4 valleys before it rushes off into 4 25ft gutters. Rain comes hard in TX and the valleys could back up and due to the very low slope, water could get under the metal roof.

In Energy efficiency and durability | Asked By Laura Parker | Mar 21 16
7 Answers

Open-cell foam in exterior wall cavities?


We want to insulate several rooms that have plaster interior and no insulation in the wall cavities (as verified in other portions of the house that were gutted). The exterior of the house is 8 inches of field stone over tar paper and sheathing boards. The house has sizeable roof overhangs and no apparent moisture issues. The insulation contractor is recommending injecting open cell foam in the wall cavities (drill and patch holes). Is there any issue with open cell foam retaining moisture from the exterior?

Thanks for the help

In Green building techniques | Asked By Douglas Wathen | Mar 20 16
6 Answers

Attachment of a stone fireplace surround -- fasteners?

Is it a code requirement or recommended practice to install mechanical fasteners to fireplace surrounds, or is mortar alone satisfactory? I'm not talking about massive columns and mantles. Just thin granite slabs (not tile) without a mantle. More specifically:

In General questions | Asked By John Walls | Mar 18 16
6 Answers

HPWH impact on load calcs

If one installs a heat pump water heater (HPWH) in the conditioned space, how does that impact the calculation of the design heat load and design cooling load?

For example, if the specs say that it uses 500 watts in heat pump mode and has a COP of 2.5, should the heat load include the (2.5-1)*500 = 750 watts that comes out of the house air? Or, is it not necessary to include the whole amount because the HPWH runs intermittently?

I am guessing that you can't take a credit for it in the cooling load since it won't necessarily be running.

In Mechanicals | Asked By Reid Baldwin | Mar 20 16
16 Answers

Vapor sandwich with foamboard on both sides of framing?

I have a 2x4-framed wall with very little cavity space for the cellulose insulation I plan to install, because windows comprise a lot of the wall, and because headers above the window take a lot of what's left. My plan to increase the insulation was:

- Install 3/4" foamboard, sheathing, and siding to the exterior.
- Add 2x2's to the interior framing, converting it to 2x6 framing.
- Install cellulose into the cavities.
- Glue 2" of foamboard to the headers.

In Green building techniques | Asked By Michael Bluejay | Mar 14 16
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