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1 Answer

What is the best heating and cooling plan for renovating an old building into apartments?

We currently have central forced air that has the ductwork going through the cold attic, and the suspended ceiling. I would like to tear out the suspended ceiling and put up drywall over the old broken lathe and plaster.

Should I run new duct work under the floor to floor registers (we have room for this since there is space above the ground floor's suspended ceiling).

Or should I install electric baseboard heat, and a mini split A/C unit.

Asked By Aaron Hirshberg | Dec 19 13
30 Answers

Window condensation issue

I'm in the middle of constructing my home and have discovered a serious condensation / bulk water issue. First some background: We're in southern Maine. The envelope is a double 2x4 stud wall system 10.5" thick insulated with Roxul. Exterior air barrier is taped zipwall and interior air barrier is ADA with taped or gasketed seems and joints. No vapor barrier. We put in Intus Eforte UPVC windows.

Asked By Brian Beaulieu | Dec 8 13
2 Answers

Wall assembly with XPS foam and stucco

I am looking for help with my exterior wall assembly. This is for a house with Stucco exterior and XPS foam. We are building a house in Climate Zone 3 (SF Bay Area). Required wall insulation here is R13, but I would like to do better and add 1 inch XPS foam to increase R value and eliminate thermal bridging.

I am confused about the appropriate wall assembly after reading several articles on GBA and other sites. Code requires "2 layers of Grade D building paper" over the OSB/Plywood.

Here are two wall assembly options I have in mind:

Option A:
1. Drywall

Asked By Thomas Schulz | Dec 16 13
4 Answers

Ray-Core panel wall detail help

I’m building a pretty simple 24’x30’ timber frame camp on a walk out foundation in western Maine (6A). Basement - unfinished, first floor - one bedroom and bath, then rest open to above, 12’x24 loft. It will have a 12/12 roof. I’m doing as much of the work myself as I can.

I’ve purchased Ray-Core (raycore.com) polyurethane foam insulated panels, 3.5 (claimed R26 – I know, I know, but let’s not go there) in for the walls and 5.5” (claimed R42) for the ceiling.

Asked By Michael ONeill | Jun 16 12
2 Answers

Insulation and ice dams

We are getting ice dams on the south and west sides of our home. We have plenty of insulation in the attic but on those two sides (south and west) there is a covered porch. There is no insulation on the soffit that covers the porch and of course no insulation in the eaves.

The porch is about 6 feet wide and runs the entire length of the south side of the home (the front) and the entire length of the west side. The east and north sides only have eaves which are less than 12 inches.

Asked By Jared Bennett | Dec 9 13
15 Answers

Insulation Re-do

I am an architect working on a 2 BR/2BA high end addition above an existing garage in the mountains of Colorado. The exterior walls are 2x6 walls, roof has 2x12 rafters, floor is 11-7/8" TJI's with 1 1/2" of gypcrete for radiant heating and tile floor. Garage below is heated and insulated. The contractor just insulated the new space and did it differently than spec'd. We caught it before drywall and he is going to go back and make changes to bring things to what was spec'd.

Asked By Rick Dominick | Dec 6 13
1 Answer

Ceiling construction in tropical fish wholesale facility

I have recently hired on as a maintenance man in a Tropical Fish Wholesale facility. Probably 1000 fish tanks and 100% humidity. After looking at the Hodge Podge of insulation boards fastened to the sheetrock Ceiling for 3 months now, (This is to keep sheetrock from falling down, and using this same method to repair 2-3 spots) I've decided to investigate the attic situation. Worst fears have been realized. It is Literally raining in the attic. Plywood covered with ice and water. Cellulose Insulation totally soaked. Flexible air ducts full of water.

Asked By grant brockey | Dec 8 13
3 Answers

Looking for some insight on using strawclay as the thermal envelope for a 2 -3 story home in Michigan.

This home needs to achieve Netzero as we are shooting for Living Building Challenge. Wondering about strategies, hesitations, cautions, or any thoughts at all. Note this is not strawbale but if you believe that work better, let me know!

Asked By Brett Little | Dec 7 13
2 Answers

Pine Beetle kill plywood as air barrier?

We are using our sheathing as the air barrier and my partner is concerned that quite a bit of the plywood sheathing is compromised because it is made from beetle killed pine. Holes are visible on the surfaces, but of course we can't see right through to the other side. Anyone have any thoughts on this? Should we be concerned?

Asked By jessie pratt | Dec 7 13
6 Answers

Fastening vertical pine lap siding over rainscreen — horizontal nailers?

I am having a hard time satisfying all our intentions in this scenario and would appreciate some timely advice.(ASAP :) If there are some available drawn details to point me to that would be much appreciated. We are are in climate zone 5A.

2x6 Wall
5.5" of Icynene insulation, will be sprayed in.
7/16 Zip wall sheathing
Tyvek - (taped with the small folds. We think its useless and have nicknamed it 'wrinklewrap')
Marvin aluminum clad windows.

Assuming we want the windows nailing fin on-top of but taped/lapped to the WRB.

Asked By Arthur Jackson | Dec 4 13
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