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6 Answers

Another “rigid-foam attached to the underside of rafters” plan

This is new construction with an all hip roof with a very short ridge located in the northern part of zone 3. I’ve ended up with a large cathedral ceiling area which opens to additional living space tucked under the roof resulting in an unvented attic. Is my insulation plan workable? Might I have future water issues? Will my stack-up breathe and dry sufficiently? What issues will the trades find with the plan? is there a better plan?

Asked By Richard | Dec 28 15
5 Answers

HVAC question

So, I am admittedly not an expert, thats why Im here :) And I know there are a ton of variables but I hope to sum this up as clearly as possible. This is all relating to heating.

Asked By rob elzey | Feb 10 16
2 Answers

Can I put up 2 kraft-faced batts in a shed roof?

I have a room with a new roof and rafters, and want to install R-30 worth of insulation by installing 2 R-15 3 1/2 inch batts, is it kosher to put one kraft-faced batt on top of another? My buddy John says that is a risk for moisture buildup between the batts but I argue that the kraft paper is not a moisture barrier, There will be a baffle above the batts to allow an air channel from the front (bottom) of the shed roof (with a soffit vent) to the top (also soffit vented)


Tom in Westford, MA

Asked By Thomas Ennis | Feb 10 16
12 Answers

Basement insulation / wall framing with limited space

Hi. I'm working on a basement in a 1960s ranch in Minneapolis, all below grade, with a concrete block foundation. I've read pretty much all of the articles here about basement insulation, and I was set on doing the following: 2 inches of XPS glued to the block, then a 2x4 framed wall, and then either XPS or spray foam in the stud bays. HOWEVER...

Asked By Jay | Jan 20 16
31 Answers

Best way to fix insulation problem in cathedral ceiling? Please help!

I built my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

Asked By Aaron H | Jan 31 16
2 Answers

Farley Windows

I recently received a quote for double pane Farley Windows from Home Depot. There price was good, and the warranty excellent. My housing situation is I'm located on a large acreage of trees (with a lifetime supply of firewood available. I'm looking at a low SHGC window, even though I'm in Prince Edward Island, Canada, since my heat is free, but I'd have to pay for AC. I'm not looking for the world's most efficient window. I just want to get good value for my money, good warranty and be comfortable in either a hot or cold windy day sitting beside the window.

Asked By Mitch MacLean | Feb 10 16
5 Answers

Add insulation to this cathedral ceiling?

We recently purchased a log home with a built up, vented cathedral ceiling. From the plans (left behind by original owner) and what I can tell from poking around the assembly from the inside is... open rafters - tongue and grove pine ceiling - 4 inches foil face rigid foam (foil towards TG pine) -- 1 inch airspace via prefabbed baffle -- plywood, felt, shingles. In our up stairs bedrooms there is additional TG pine on the bottom of the rafters (presumably to match the TG pine on the dormers where they are no exposed beams). See attached sketch.

Asked By John Carr | Feb 10 16
37 Answers

Will minisplits work in all floor plans?

I'm researching the details of building a new house in central KY, zone 4a. This will be the house that lasts for the rest of our lives (hopefully 50+ more years). I had assumed that GSHP were the "no-brainer" HVAC choice, but from the looks of things, it isn't that simple. I've been reading some amazing things about the potential of mini split systems.

Asked By Clay Whitenack | Jul 20 15
1 Answer

Do I need to install rigid insulation in the bottom of a walk-in refrigerator before I install tile?

I am being hired to remove the failing metal floor and install quarry tile in the bottom of a commercial walk in refrigerator. The existing floor has 4" of insulation, then plywood and then metal floor on top of the wood. I believe the existing insulation is in very poor condition and possibly wet and I am planning to remove all of it. This is in a restauraunt in southeren California which is on the second floor of a commercial building where there is a structural slab as the foundation and there is occupied space on the first floor below.

Asked By Jim Jelinski | Feb 10 16
1 Answer

Drywall above stud wall framing good for fireblock?

First off, the website has been a wealth of information and a great help so thank you. I'm in the process of finishing my basement and have put 2" XPS in the rim joist section and plan to follow-up with 1" XPS on the interior walls followed by the framing in-front of that. For a fireblock, is 1/2" drywall safe in the basement to attach to the joists and then butting the top of the XPS against along with the top plate of the stud wall? I assume this would be an acceptable fireblock but not sure if the drywall would be a safe bet.

Asked By Jason M | Feb 10 16
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