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39 Answers

Questioning my logic...GSHP, ASHP, radiant?

I'm in the planning/almost ready to break ground stage of a new home and I'm beginning to question my sanity when it comes to figuring out the right approach for heating & cooling.

The home is:
North end of Climate Zone 5
Main Floor: 1700 sq ft + 1000 sq ft garage, vaulted ceilings through much of it
2nd Floor: 1100 sq ft (2 bedrooms, 2 baths, living room) primarily over the garage
Basement: 1700 sq ft, partial walkout + 1000 sq ft shop under the garage (separated from the rest of the basement)

Walls: R30+ (2x6, 2" XPS outside, 2lb SPF for sealing + 1/2lb SPF for cavity fill)

Asked By Dave De C | Jul 16 16
3 Answers

We are building a 700-sq.-ft. cottage on southern Vancouver Island, Zone 4 Marine

The plan is to use 4 inches polyisocyanurate - R22.6 - (glass fiber covering) exterior insulation no sheathing except for earthquake walls. No insulation in the 2x4 wall cavities, tyvek on the exterior of the foam and vapor barrier between the polyiso and the framing. ls this ok or will we have problems. We have to present our wall assembly plans to the city and the city wants a vapor barrier but we are not sure if this is necessary.
Sandra Garraway

Asked By Sandra Garraway | Jul 22 16
4 Answers

Exterior walls to meet code without gypsum?

Hello,

Maybe this has been discussed here. Feel free to link me to other threads that I haven't seen if this is fully covered elsewhere.

I'm not a fan of drywall. A quick rundown with no real surprises: it used to be cheaper; now it's not. It also takes plenty of work and more money to make it look nice. It's heavy but also very breakable. Even when you don't break it, it's messy. Etc, etc. I *am* a fan of 3/4 plywood, which is less breakable, more durable, and looks nice.

Asked By Minneapolis Disaster, 6B | Jul 22 16
20 Answers

Ramblings on thermal mass, AC and window fans

This is isn't really a specific question so feel free to offer random thoughts

Asked By Alan B | Jul 10 16
15 Answers

Fluid WRB at big box stores?

Hello,

I am interested in building a workshop/studio 16'x12'x12' and am interested in using a WRB. I read the wrb in a can article on this website and lots of other information on the subject. When I look at the mentioned products, they do not seem to be accessible in local stores or something that a non-contract professional can find. Is there a Home Depot or Lowes type solution? This studio will be assembled in the order of a 2x4 framed, OSB sheathed, fluid WRB, drain wrap, 3" XPS and seam sealed, rainscreen, fiber cement.

Asked By John Haller | Jul 21 16
5 Answers

Tying in Addition Roof

I'm having trouble finding definitive answers on how to tie in my additions roof.

The home is a basic ranch roof, no dormers on the addition, just a straight roof. I'll be tying the addition into the gable end of the existing home using the same roof pitch and truss design for the most part.

-Should I just snap a line and cut the eave, including shingles and fascia right off? I know the fascia will have to go to get the new truss in at some point.

-Do I need to weave in the plywood to the original roof if there will be a new truss sistered up to the gable?

Asked By Mike M | Jul 20 16
7 Answers

Spam

I see GBA is being attacked by spam. I don't want to give this more attention than it deserves, but can someone tell me why this occurs? What benefit is there to whoever fills the Q and A with this content? If my question is some way aids them, please delete it.

Asked By Malcolm Taylor | Apr 21 16
1 Answer

Insulating a sloped ceiling

I have a 1.5 story home built in 1900 in southern NH. Minimal insulation on attic floor and some stuffed into the sloped ceiling from the attic. The insulation contractors that have looked at it want to dense pack the bays on the sloped part with cellulose. One said he could flash it with spray foam to seal it first, then dense pack. I have read that insulating with no venting is a bad idea. I understand without ripping the drywall down, it would be very difficult to insulate properly and add vent chutes.

Asked By Frank Mengler | Jul 22 16
10 Answers

Unvented cathedral ceiling — insulating from above

I am re-doing my family room roof, which is a cathedral ceiling.

Since the roof is being re-shingled, I thought it a good time to remove the sheathing and lay down some closed cell foam. I have some unopened from a previous project

Everything I've read about unvented Cathedral ceilings talk about them drying from the inside. Obviously this can't happen if I'm spray in the closed cell foam onto the dry wall ceiling from above

The ceiling is 8" from drywall to plywood

Asked By Paul Buchkowski | Jun 25 16
2 Answers

Replacing insulation in basement

Hello, I have a 3 year old basment with 8ft concrete walls that was finished with 2 by 4's that are about 1/2 inch off the concrete wall and fiberglass batting was used as insulation which I don't believe is the correct material. If i want to replace this should i go back to the studs and perhaps do a spray insulation or is it best to take everything out and start afresh. At this point i do not have any mold/smell issues but also think it could just be better insulated. I am in zone 5/6, right on the edge. Thank you.

Asked By J D | Jul 21 16
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