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1 Answer

Reclaimed Iso/Strapping/Sheeting/Shingles?

Hi there, I was trying to piece together an answer by reading already posted questions, but I thought I should just start a new thread. What I want to do:
Strip the two layers of old and failing shingles, check the existing sheathing, replace anything that needs replacing, cover the roof with 3" (maybe) reclaimed Iso insulation, strap that, sheath it, shingle it.

My concerns:
If I go with reclaimed I so I am concerned about nail holes and such. I have been wondering if I should cover the insulation with a breathable house wrap, then proceed with the rest of the roof structure?

In General questions | Asked By Alfred Dedam | Mar 23 13
3 Answers

Ventilation ducts in exterior walls

I'll need some form of duct to get fresh outside air to my ERV and another to dump the exhaust..
I'm building with double stud walls insulated to r40 whole wall. The ERV will be in the basement. I have a place where I can in effect move the walls inward so the duct will be outside the insulation as it crosses the sub floor. Is there any reason to use insulated duct? Would a rectangular duct made of fiberglass "duct board" work? Any reason to not use galvanized steel 'sheet metal' duct sections?

In Energy efficiency and durability | Asked By Jerry Liebler | Mar 22 13
11 Answers

What is the current approximate cost of an exterior wall in $/foot?

There is a beautiful remodel underway in my neighborhood, and the front facade of the house uses nanaWall, to wonderful effect.

I have mountain property and have been thinking through the possibilities for a new house there. View is incredible, as well as incoming solar radiation. So this application would be great, if i can afford it.

I have the cost of nanaWall from their website as $600-1950 per linear foot (the high estimate is for Dade County, FL hurricane codes. I will not need that for the mountains of Virginia), but i would like to know how to compare.

In General questions | Asked By cheryl phillips | Dec 10 11
14 Answers

Do rainscreen details make the home less fire resistant?

I consider rain screen details on exterior walls a mark of quality/intelligent building...but I had a thought that came up as I was considering what this wall would do in the case of being exposed to a fire, with the source being outside like in the case of a forest fire.

While the home may be sided with non-flammable siding, there is a nice air gap and plenty of oxygen flow behind this siding with the flammable plywood behind it.

Could this design to quickly dry your home, also quickly compromise it in a forest fire?


In General questions | Asked By Eric Mikkelsen | Mar 19 13
14 Answers

Is radiant barrier necessary for staple-up radiant heat?

I took a local builder's advice and put R-19 batts under the radiant PEX, rather than a radiant barrier like the foil bubble foil, but after reading more I'm worried I made the wrong move. The heated floor is above a half crawl/half basement space. Thanks to this forum I air sealed and insulated the band joist so the crawl/basement is about low 50's when it is single digits outside

In General questions | Asked By Michael schlee | Jan 22 12
2 Answers

Insulating a circa 1900 house (gut-rehab)

I live in VA, zone 4A. I am trying to decide how to insulate a circa 1900 house with the interior completely gutted. It is a two story ballon-framed house with a brick foundation and a tall, steep roof. It has a standing seam metal roof in good condition. It has lap siding attached directly to the studs (i.e. no sheathing). I am considering foam and fiberglass bats for the walls (2 in of spray foam) and cellulose for the attic floor. I have also been reading this site's posts about sealing up the crawl space and am planning to do this as well using foam board on the walls.

In Green building techniques | Asked By Duane Barron | Mar 15 13
9 Answers

Double stud walls - vapour retarders

Good day folks. I am in a cold climate (Halifax, NS, Canada) climate zone 5 or 6 I think???

I am constructing my house in the spring and will be using some variation of the DBL stud wall; either the Riversong DBL bearing wall, or constructing the house conventionally then stand up walls from the inside. I will be going for 10-12" thick. My main question is about air leakage control, and vapour control. On the inside I am going to likely do ADA, and on the outside is it overkill to use adhesive on every stud and plate before I attach my 1/2" PLY and then tape all the seams?

In Energy efficiency and durability | Asked By Mark Pennell | Mar 15 13
2 Answers

Climate Zone 7 Colorado

I'm struggling to understand the use of Rigid foam on exterior of a home, new construction. I understand the benefits and want to use it. I would like to use from the interior wall out, 5/8" drywall, smart vapor retarder, blown in BIBS, Zip System sheathing, polyisocyanurate per the code R-15, for a 2X6 wall all seams taped. Apply wood siding over foam.

Questions: Should my wall cavity be filled with insualtion to meet current code 2012 R-20 or can I use a portion of my R-15 Rigid to makeup the required R-20 cavity and R-5 continuois sheathing?

In GBA Pro help | Asked By Forrest Watson | Mar 22 13
7 Answers

Selecting an HVAC and hot water systems

We are building a new house. I need to select the guts for the heating/cooling. Solar and geothermal are not feasible. How does one whittle down the options/brands/models for a high efficiency (.95+) gas furnace? My builder is recommending a Trane furnace and cooling units. For hot water, he is suggesting tankless Navien units (NR-240A). I'm just not sure how to consider other brands and/or options. Any suggestions are greatly appreciated.

In Mechanicals | Asked By scott sch | Mar 19 13
1 Answer

What needs to go behind a shower surround on an exterior wall with 2" of exterior foam sheathing?

I have a client doing a whole house remodel. They've already wrapped the entire exterior with 2" of EPS and are insulating the interior with blown in fiberglass. What insulation / air sealing is needed behind the fiberglass shower surround on an exterior wall to achieve a dry, air-sealed envelope? Can they get away with just fiberglass batts there or is a rigid air barrier needed on the interior?

In Green building techniques | Asked By Elizabeth Coe | Mar 22 13
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