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27 Answers

I thought I was on the right track but I am not so sure now ...42000 btu is the heat loss number .It is a 1200 sq ft slab on grade 1.5 storey .Total living space is 1900 sq. feet .It is 2by 6 blown in fiberglass with 2.5 inches of EPS on the exterior .We do have lots of triple pane large high windows on the lake side which is a north east exposure ...,that one large combo living,kitchen,dining room is a 17000 btu heat load .I was hoping to heat it with a Fujitsu mini split on each level ...Is that still a viable option ? I am in Peterborough Ontario which is a zone 6 ...thanks,Bob

In General questions | Asked By bob holodinsky | Jul 8 14
1 Answer

The cathedral ceiling roof assembly on a recent addition to my house consists of vented fiberglass-filled bays with with an interior layer of 1/2" foil-faced polyiso under the 2x10 rafters.

Investigating a strong odor on hot days, I found that the builder...

Michael Roland,
Nassau, NY

In Green building techniques | Asked By Michael Roland | Jul 16 14
3 Answers

Isn't there an intrinsic problem with SCIP (structural concrete insulated panels) that the reinforcing trusses bridge the insulation.

In General questions | Asked By Stephan Green | Jul 14 14
1 Answer

I’d like your recommendation on sealing rafter bays of a currently vented cathedral ceiling.

I’m doing a remodel of a small room (20 X 20 feet); the roof/ ceiling were built as a vented roof assembly complete with a ridge and soffit vents.

In General questions | Asked By Anthony Jackson | Jul 15 14
3 Answers

My proposed wall assembly from outside to inside:

1. Ribbed steel siding
2. 3/6" fanfold battens to create air space
3. 1/2" cdx
4. 2x8 stud cavity filled with wet spray cellulose
5. 2" eps nailed to studs (interior uninterrupted rigid foam)
6. 1.5" uninsulated service cavity (created with horizontal 2x4s)
7. 3/8" acx plywood (interior wall finish)

The building is a heated workshop with some pretty high electrical needs for the machinery. Since it's not a residence, I could probably forgo the fire blocking.

In Building Code Questions | Asked By Rick Van Handel | Jul 14 14
3 Answers

I want to properly insulate a basement wall to which dimpled Delta MS has been attached up to grade level, as part of installation of interior weeping tile/sump pump installation.
How should I adhere xps or eps insulation to this wall, since the dimpled Delta is not exactly even with the concrete on the exposed part of the wall above it?
Or is it necessary to buy more Delta to go all the way to the top of the wall?
In either case, what is the best way to attach the insulation?
(I intend to frame a wall later in front of this insulation.)

In General questions | Asked By John Lawson | Jul 14 14
11 Answers

Basements are almost unheard of in Texas.
I always thought that basements were almost mandatory "up North" because of frost heaving problems.

I have recently noticed many cold climate examples that do not employ basements.

Most noteable..... German Passivhaus examples.
Almost all of the modern German examples do not include basements.

After seeing a video of Dan Morrison's basement .. I can see why youz guys may be reluctant to give up your basements ;-)
In Texas our Garages look much like your basements..... "Full of Stuff"

A basement is a deep crawl space...

In General questions | Asked By John Brooks | Feb 25 10
2 Answers

I have read your comments extensively and find the information very helpful. However, I have several concerns about my proposed construction.

I plan to construct a vented cathedral ceiling using pre-engineered wood trusses at 24" on center with 2x12 top chords in a Zone 4A location. The IRC 2012 allows R-30 for cathedral ceilings less than 500 SF or 20% of the total roof and my project qualifies for this exception.

My proposed construction includes:
1. Composite polymer shingles over Zip-system 5/8" sheathing and ice dam protection at the eaves

In Energy efficiency and durability | Asked By James Enloe | Jul 14 14
1 Answer

(Zone 4c)

In Energy efficiency and durability | Asked By Nick Welch | Jul 14 14
3 Answers

I am building a earth-sheltered passive block home. I want to insulate it all from the outside. I have been trying to get Roxul Drainboard in 3.5 inches but cannot afford a whole truckload to do a small home. So I'm thinking of using 4 inches of XPS foam under slab and all walls.

Any suggestions for water proofing exterior of block and fastening XPS to all the walls?

Thank you.

In General questions | Asked By michael holler | Jul 11 14
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