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42 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
4 Answers

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
8 Answers

Leaky Ductwork in Basement

After getting a very poorly rated energy audit from our electric company, I'm working diligently to get our house more air tight. Seeing lots of posts about HVAC equipment, I'm thinking ours is a little lacking. It is 5 years old, the furnace is 95% efficient. But, the black tape is falling off and according to infrared, it is leaking. I've attached several pictures and also infrared pictures. We are in zone 5 (NW MO). It is 20 degrees outside and our basement walls are 47 and 53 at the frost line.

Asked By Becky Parrish | Feb 9 16
2 Answers

How do I calculate the interior temperature of a window at a given outside temperature with a fixed interior temperature?

I am trying to predict at what outside temperature will I get condensation on my windows. If it is 70 degrees inside with 40% relative humidity and my window has a u-value of .3 at what outside temperature will the window (frame and center of glass) have condensation. How do I calculate this?

Asked By Chaz Steffen | Feb 9 16
5 Answers

Radon venting in 1/2" crushed rock?

I have about 9" of 1/2" crushed stone as a base for the slab (2" of foam will go between stone and slab). I searched for clean, no fines, and the best I was able to get is mediocre clean.

Will installing 4" perforated PVC pipe in this material still work as a radon vent?

Would the efficacy be improved if I backfilled the 8" deep x 8" wide trench for the pipe with 3/4" rock?

How long should the pipe be?

Thanks.

Asked By David McNeely | Feb 9 16
1 Answer

Bathroom ceiling

I am going to be installing t&g pine (sealed all 4 sides and ends) on a bathroom ceiling. The ceiling is below an unvented roof and conditioned attic space (8" closed cell foam in rafter bays). Climate zone 8.

I want to know if I should install the t&g directly to the framing members or to put up drywall first. I already have an ignition barrier over the foam. Will drywall just be a surface for mold and mildew? I have a Panasonic whisper green vent fan and a window in this 72sq ft bathroom.

Thanks

Asked By Jon Patrick | Feb 6 16
25 Answers

Final advice on insulating a basement correctly

Hi I’ve read the great articles here on how to insulate the basement correctly - I just want to make sure I'm going to do the work right and I trust the folks at GBA

Overview

• Southern exposure home – south has 2x6 pt walls with a few windows and doors (basement level)
• North has an 8ft concrete wall that behaves like a huge cooler – it also has a 24inch 2x6 pt wall on top of that, so the basement ceiling height is 10ft.
• In the worst heat in summer 90 degrees + the basement is extremely cool with the windows closed – just like air conditioning

Asked By Robert Metelsky | Aug 4 15
32 Answers

Roxul board used in basement as insulation against concrete wall?

I just watched a mike Holmes episode. He was building out a basement for bar, home theater, gym, etc. against all the walls he used roxul board as an insulation barrier then the walls were framed. I've read where Martin Holliday advised against this practice. Who's right? It makes more sense to use foam or foam board as it won't hold water. Thanks for any clarification on this topic.

Asked By tim gabriel | Mar 5 15
12 Answers

New roof, new skylights, new condensation... and not a lot of answers. Any help?

Hey everyone. I don't normally post to anything but I'm at the end of my rope and not sure which experts I can trust so looking for some extra opinions before I go and do nothing or start making tons of holes in my roof.

Asked By S. B. | Jan 24 16
0 Answers

closed or open cell

you have helped me before. i have decided to do a spray foam insulation. the building is pole barn type build [wood] covered in sheet metal. it has a concrete floor,insul garage door an it will have a/c only, it also is located in central fla. i,ve had 3 different contractors with 3 diff ways of doing it. one is closed cell on walls an roof an he said 1/12 "" is all thats needed. he had the best price [ still not cheap]. the next guy wanted to close cell the roof an open cell the walls.

Asked By bill metzger | Jan 31 16
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