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17 Answers

How to fix my unvented cathedral ceiling roof assembly?

We tried to build a house with a fairly tight envelope based on reading I could find. Well, apparently I messed up, so really want some advise before I mess things up more.
House is in central Missouri( zone 4, but real close to 5). Small, 750 sf but with an open loft making it about 940sf. Sealed Concrete slab as the finished floor, and new construction ( under roof in may but moved in The next January). Red metal roof and one side of that faces north..
Walls are 2x4 and we used open cell foam with 1/4" foam inside the studs as an air ( not vapor) barrier.

Asked By Brenda K | Feb 16 17
4 Answers

Dense packing cellulose with the Krendl 425

Hi All,

I am going to attempt to dense pack several horizontal stud bays (2x10 floor joists, 12in o.c., between attached garage and bonus room) using the Krendl 425 (14amp 2-stage blower, pushing 1100 – 1400 lbs of cellulose per hour) over the upcoming weekend.

Asked By Joe Duchek | May 23 17
13 Answers

Can I combine floor and wall heating in a solar passive house to avoid overheating?

I have consulted many "experts" on highly insulated houses, most of them recommend to use ductless heat pumps to heat the house. But I am a radiant heat addict...
Apparently the problem with radiant floor and passive solar is that when the sun comes out, the southern side of the house is too hot because the concrete slab has heated during the night and is warm and when the sun comes out it can bring it to a much higher temperature.

Asked By Micheline Freyssonnet | May 22 17
1 Answer

Attic Baffle Height

I'm going to be blowing in cellulose into my attic. I've installed ventilation baffles, but I'm wondering how much cellulose I can add? How much higher does the top of the baffle need to be compared to the level of the loose cellulose? Thanks. -Andrew

Asked By Andrew G | May 25 17
7 Answers

Building new home in Delaware and using insulated Zip exterior sheathing

Addressing the stud cavities, should I tape or caulk zip insulation to studs or is the compressed sheathing insulation to stub enough.

Asked By Edward Serafin | May 24 17
17 Answers

Well water pumps

Is there any preferred efficient water delivery systems from a well? The constant pressure systems were mentioned sometime on this website, but I don't know if that was for space or efficiency.
Grunfos was the brand mentioned.

Asked By Steve Young | May 24 17
0 Answers

Retrofitting garage to a heated shop - slab and wall details

Hi all.

I am soon to be owner of a house with an attached garage, roughly 20x30. I would like to convert the garage to a heated wood shop.

I am in climate zone 6A (Maine). I will have consistent heat in the shop, probably in the 55 degree range, bringing it up to 60-64 for working temp. I am leaning towards heat pump as heat source.

The garage is a concrete slab, the details of the footings/stems I do not yet know however.

The structure is 2x4 studs sheathed with (I believe) T1-11 exterior ply. Roof trusses (not raised heel). Stud bays currently open to inside.

Asked By Tyler Keniston | May 25 17
0 Answers

Crawl Space Insulation Options

House is 1-story 1200 square feet, CA climate zone 3, zip code 95062, about 1/2 mile from the ocean. Existing ventilated (passive vents) crawl space has 18" clearance, 48" OC 4x floor joists under sub-floor, perimeter foundation and piers along joists. Clay soil is damp, but downspout diversion and french drain in back yard keep the space from having standing water. House is heated by hydronic radiant heat system, on top of subfloor in 1/2" sleepers.

Asked By Phil Boutelle | May 25 17
6 Answers

Slab on grade and wet room floor question

I am working on a "Tiny House"-type structure (12 x 16) that will have what seems to be referred to as a "Wet Room" for a bathroom in which the shower can use the entire room. This will allow me to keep the bathroom's footprint low. Anyhow, the floor of the space will be a slab on grade and the floor drain in the wet room will of course be pitched correctly. I do plan on insulating under and around the slab floor but I may acutally use furring strips to put in a floating engineered (wood or cork) floor for the living and kitchen space for a more comfortable surface.

Asked By John Brown | May 25 17
0 Answers

Bathroom exhaust ducting plan

I'm in the process of roughing in a new bathroom in my basement. I'm looking for feedback on my exhaust fan plan. Bathroom is 5x11, eight foot walls. The fan will sit in the joist bay (obviously) and the duct will run about one foot in the bay to the wall, where I then need to drop the duct below the joist to run it along the wall in a chase for about 18 feet. At that point I hit a plumbing obstruction (main stack). I plan to use flexible duct for the first two feet, PVC for the next 15ish and flexible again at the end to get around the stack.

Asked By adam stanton | May 25 17
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