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3 Answers

Housewrap vs building paper

I am building an energy efficient house in Victoria, British Columbia. The wall system is 2x6 construction covered with 1 1/2" XPS for a nominal R-27. The XPS will be calked at the perimeter and all joints taped to form the air barrier. In my municipality the Code requires that the the walls have a rain screen (it is actually a 1/2" capillary break) and two planes of protection against water intrusion. The siding material constitutes the first plane of protection.

Asked By Ross Neuman | Jun 30 11
5 Answers

Flash and Batt

Hello, I have been reading so much about flash and batt lately I am second guessing my original plan to insulate a home we are building. We had anticipated dense packed cellulose walls (9 1/4" cavity) and 24" of blown in cellulose in the attic. Are there significant reasons to flash both or either of these areas with foam first? If so should I just go to an open cell foam for everything? Seems like much of what I am reading is contradictory, what is the right choice here?

Asked By james magner | Jun 16 11
2 Answers

Options for remodel plaster walls - insulation, electrical, plumbing, HVAC upgrades

I have recently purchased an older home (1930s) and plan to renovate. But I cannot seem to find the correct resources on the web to help me make informed decisions. I am hoping this forum might be the correct place.

The house is a two-family, each floor is a separate unit but there is a shared entrance and basement. The home has plaster walls some in good condition some are cracked. I plan to renovate the second floor first. I have a series of questions about repair options and the types of professional with whom I should be speaking.

Asked By Tyleisha Baez | Jun 5 11
1 Answer

Rigid foam under a vaulted ceiling

Is it possible or even a good idea to use rigid foam ,(xps or poly iso ) under the drywall on a vaulted ceiling.The house is in zone 5 with sissor trusses in this area. Above the ceiling is R38 fiberglass with venting at the soffits and ridge.The ceiling would then be refinished with drywall or wood paneling.

Asked By David Gervais | Jun 5 11
0 Answers

LEED for Homes Gut-Rehab - CA Title 24 Calc NC or EB?

Hi -

The 1895 Green Castle project I’m working on is an existing home, major “gut” rehab that obtained permit Jan 2010 and qualifies as a candidate to obtain LEED for Homes Platinum in CA.

Overall and, specifically within the Energy & Atmosphere category, should we use CA Title 24 calculations for new construction or existing building?

J Co

Asked By J Co | May 31 11
5 Answers

Hydro vs furnace? And rigid strips on the inside?

Hello, I have two unrelated questions.

First, in a home with walls approaching R-40 and roof at R-60, that is relatively "tight", should we consider a modulating boiler/hydro air heating system? Or is a modulating furnace a better option keeping costs in mind? I guess what I am asking is, is there any truth to a furnace providing a "dry" heat, compared to a hydro system? And, if so should it be a consideration in the decision making process?

Asked By james magner | May 23 11
1 Answer

Silane/ Siloxane Masonry Sealer

Does anyone know of any case studies that have been performed on the use of a silane/siloxane masonry sealer on a historic clay masonry structure? If not, does anyone have personal experience with this product good or bad?

Asked By Josh Eaton | May 18 11
39 Answers

Timber frame with 8-in. XPS wrap-and-strap assembly: What have I gotten myself into?

24-foot square timber frame with "REMOTE / PERSIST" envelope, from inside to out: timber-frame post; drywall; horizontal or vertical 2x4 'studs' 16 in. on center without insulation; staggered sheathing; peel & stick; 8 in. XPS; 1" or 1-3/4" furring attached through XPS to 2x4 framing with 11 in. SIP screws, (fastened at an angle) 24 in. on center, and a mix of clapboard, board and batten and shingle siding.

Asked By Ryan Shanahan | Dec 4 10
2 Answers

When finishing a basement floor to increase living space, should a vapor barrier be laid under flooring material?

I live in Oregon, somewhat damp environment, in an 90 year old house.
I get moisture moving up thru the basement floor. IE if I lay a stack of magazines on the floor, they wind up sticking to it. I have done as much rainwater diversion on the outside as I can.
I was thinking about installing a cork floor. If I lay down plastic under this will this cause me issues due to the moisture not being able to migrate upwards? Will water build up beneath the plastic vapor barrier?
Would it be better to use some other flooring, like tile or another vapor permeable material?

Asked By Vincent Alvarez | May 4 11
3 Answers

Insulating a fully below-grade cellar with an uneven rubble foundation wall

Hi all!

I’ve read almost every article AND every comment/question & answer on this topic but haven’t yet seen anyone with this exact dilemma so I really hope you all can help advise: (You guys have been GREAT so far)

We are wanting to insulate the walls in our fully below grade cellar (with a poured-concrete floor and an uneven RUBBLE foundation wall.

Asked By Michael Anthony | Apr 30 11
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