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17 Answers

Insulation delirium

I've been searching and searching and searching some more on the topic of insulation and have managed to find myself in a state of mental nausea trying to sort out what I think is best in my situation; so I finally decided to ask you all.

I am soon to begin construction on a cabin in northern Wisconsin. It is a 1 1/2 story 20'x32' with cathedral ceilings and a loft above about 1/3 of the back of the building. The loft also has two shed dormers on both sides for extra head room.

I have chosen to go with 2x12 rafters with a ridge beam and am thinking about going unvented.

Asked By Andrew David | Aug 1 13
9 Answers

Questions on re-siding entire house

One story 1977 Texas ranch style tract house, 3 sides brick veneer, southern facing rear 4 th side original delaminated T111.

The plan:

T111 - remove deteriorated southern facing T111, remove existing 3.5" FG batts, spray foam to fill 3.5" void (interior sheet rock remains). New sheets of OSB overlaid with a rain screen. Primed PT furring strips (ripped from 1/2" PT plywood) placed over stud locations and tacked on top of rain screen. Then 4X8 sheets of fiber cement panels nail gunned through furring strips & OSB into original studs.

Asked By Ken Ackerman | Jul 26 13
8 Answers

Trim bottom of rigid foam on exterior of house with slab on grade

Hello, I live in Maine, I have a stick built with osb sheathing with drain wrap over that. I plan to do 2" rigid foam on the exterior walls. The house sits on an on grade 6" cement slab with a 4.5" pressure treated sill. There will also be 3/4" strapping with clapboard siding. I am lost as to how I trim out the bottom of the whole ordeal.

I plan on keeping my siding 8" from the ground, to meet code, so the foam will be exposed. Also, bugs could come in from the underside. I also have not seen a prefab drip edge of some sort to put along the bottom prior to the foam.

Asked By Karen Twidwell | Aug 2 13
10 Answers

What is the solution for our brick chimney/ceiling?

I saw the article by Joe titled Efflorescence = Water Damage — Building Science Podcast and had a question relating to possible efforescence on my chimney and walls/ceiling in my home. I own a farmhouse built in 1900. It has an old chimney used to vent our boiler and hot water heater. We have a mudroom that connects the garage to the house and within the mudroom that has the roof above it. The mudroom has a part of the chimney that has been finished to create a wall.

Asked By Page Hyler | Aug 2 13
3 Answers

Confused about new roof / decking / insulation job

Hi, my name is Todd and I'm very confused about what to do. My insurance company has agreed to replace the roof, including the decking (sheathing), and ventilation, in my cape cod home in Dayton, Ohio. I have a refinished, vaulted second floor, with a small attic peak. All of this was there when I bought the home 3 years ago (I think it was done in 1998). Thinking this would be a chance to improve the insulation I began to investigate what to do. Now I am completely baffled, both online sources and contractors have given me such divergent advise.

Asked By James Todd Uhlman | Jul 30 13
6 Answers

Is this what dense-packed cellulose is supposed to look like?

Hi all,
I'd be interested in other folks' opinion on this. I paid an insulation contractor to dense pack an unvented vaulted ceiling in my home a little over 2 years ago. I started experiencing some pretty bad moisture problems in the past month or so with the ceiling and exterior soffit. A couple of the seams of the sheetrock inside the house are starting to show on the ceiling and the outside soffit drips even when the sun is out.

Asked By Tony Fiore | Jul 30 13
1 Answer

New steel building

I live in Dallas TX, zone 3A.
I am in the planning stage of a steel building. The building will be ~2000 sqr feet & 16' walls. I plan to section off one corner of the building to be an office space but plan to cool the entire building, 2 zones. If orientation matters the large doors will face almost directly north, with a west wall that will get direct late day sun during the heat of the summer.

The standard wall construction used by the builder I am working with is constructed like this. From the outside in.

-Steel sheeting

Asked By Jeff Kirkpatrick | Jul 31 13
14 Answers

Zone 5/6a Vinyl Residing - Double Blueboard, Wrap?

As a follow up to:

Dow SIS is not available in this area, so we will insulate the walls as they are:

kraft faced fiberglass insulation (very, very thin)
two 1/2" layers of fiberboard as sheathing
one 1/2" layer of blueboard

My thought is to dense pack cellulose in the walls, tape the existing blueboard, add a second 1/2" layer of taped blueboard, possibly wrap, then side.

Asked By J Heckmann | Jul 14 13
2 Answers

Interior sheathing with outsulation?

I am designing and building a tiny house on wheels (in climate zone 6) and the wall assembly I have come up with is a little bit unconventional. I would like to use the PERSIST method, but due to size limitations this is not possible. The wall section I have come up with is a little like PERSIST though:

From interior to exterior:
-7/16” OSB (sheathing & interior finish – applied using caulk)
-2x4 wood studs @ 24” o/c filled with 3-1/2” XPS
-3” XPS over the studs
-Solitex MENTO 1000 WRB (38 perms) -taped continuous air barrier
-vertical ¾” furring strips
-open joint timber cladding

Asked By Travis Marttinen | Jul 20 13
4 Answers

Horizontal roof strapping for ventilation?

I am building a 16'x24' house in Alaska, 12/12 gable roof using 2X12 rafters, with a cathedral ceiling. A friend has recommended venting the roof by strapping the rafters horizontally with 2x4's at 16" o.c., thereby allowing cross ventilation from gable to gable. The roof would be sheathed on top of the 2x4's. I haven't been able to find any information on this technique on the web.

Asked By Justin Smith | Jul 15 13
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