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6 Answers

Spray foam directly on underside of roof?

I have a conditioned attic, currently insulated with R19 fiberbatts between the rafters. No airsealing, hence I want to remove the fiberbatts and spray 3 inches of closed cell spray foam in before putting the fiberbatts back in place. The attic is unvented, for instance no ridge vent exists. Should I put any membrane or the like on the underside of the roof sheathing before spraying the foam in ? I was thinking that would help with keeping the insulation intact in case the roof needed repair later on?

Asked By matthias paustian | 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
4 Answers

Homemade dog house insulated panels

I'm having to make a homemade dog house for my rather large Akbash mountain dog family (papa, mama and 12 wk old pup). I live in Region 5, western Colorado. I need a floor panel, roof panel, and 4 wall panels. I had this design for making the panels utilizing empty water bottles. What do you think? Will this work well enough to keep in heat and block outside cold air? I wish I had some idea of the R value. Cut 42" long x 36" tall 1/2" thick thick plywood panels. Glue 2x4s around inside edge of each wall panel perimeter, on the wide (4") side.

Asked By Andy Nels | Feb 7 16
0 Answers

Do they sell Dow Thermax anymore?

I have a big basement I need to insulate from the interior and I'd like to avoid the cost of framing and drywall since the basement will only be used for storage.

Do they still make Dow Thermax? I can't seem to find it anywhere. Is there a new product that meets the fire ratings as Thermax, that won't require drywall over it?

Asked By Clay Whitenack | Feb 9 16
1 Answer

A couple of renovation questions regarding my 1960 Cape

Hello all, I was looking up information on housewrap, and stumbled upon this website, what a great find. Anyways, I’m hoping to get some information/advice as the best way to go about doing some renovations this spring/summer on my house

Asked By Khouri Rice | Feb 9 16
31 Answers

Best insulation for indoor air quality?

I cannot decide on a type of insulation for our new home. I want something that is the safest for indoor air quality. I am worried about the off gassing of spray foam, but am also worried about the borate used in blown in cellulose (mainly the reproductive effects of borate). Please help! I want energy efficiency, but indoor air quality is of primary concern. Thank you!

Asked By Carolyn Farrow | Feb 8 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
7 Answers

Reducing noise transfer between rooms through ducts

In our current house which has all rigid metal ducts, noise transfers easily between rooms through the ductwork. For our new house, I want to make sure that the HRV ductwork does not have the same problem.

Flex is often maligned but it seems as though it could be useful in limited quantities. Based on what I read here, it seems that running a short section from the metal trunk to each room, while making sure the section is straight, pulled tight, and sized for the proper airflow (which probably makes this section upsized from the metal diameter), should not cause a problem.

Asked By Nick Hall | Feb 2 16
1 Answer

Does a rainscreen assembly maintain the exterior surface of paint?

I am trying to argue for a rain screen assembly. Is there any evidence that would highlight extending the time between painting the exterior siding by using a rain screen?

Asked By Julie Klump | Feb 9 16
7 Answers

Using a second water heater as an indirect fired tank?

I have two water heaters. A 50 gallon HTP Phoenix Light Duty propane water heater, and a 50 gallon electric resistance water heater. The two heaters are plumbed in series, electric water heater first, then propane. To make a long story short, some things didn't work out as originally planned, and now I'm paying an extra $15-20/month (and wasting source energy) because I'm heating up a bunch of water with electric resistance right next to a high efficiency propane water heater.

I'd like to stop doing that. I have a couple of extra constraints:

Asked By Tim C | Feb 8 16
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