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16 Answers

Banging noise from thermal expansion/contraction

My dwelling has cathedral ceilings and we have a problem with thermal expansion/contraction causing a "banging" noise after sunrise and at sunset. I have a high moisture reading in the morning and but the attic temperature is close to the outside temperature and by mid-day, the spread between the attic and outside increases to around 20 degrees and the moisture reading will goes from wet to dry. At the recommendation of 3 roofers, I had ridge vents added. The overhang is only about 10 inches but has vinyl venting all the way across. There is no venting on the side eves.

Asked By David Burns | Jul 27 16
2 Answers

Open cell foam contacting hot water heater flue

I have open cell foam being put into my attic. My hot water heater is in the garage below, but where the flue goes through the rafters, is it OK for the open cell foam to contact around the flue? If not, how much of a gap is left around it? I guess they would have to just cut that gap after foaming since the foam isnt going to just cooperate....

Asked By John Sexton | Jul 27 16
8 Answers

Zone 6 dew point

Would a 2x6 wall with:
R-23 Roxul Batts in the cavity,

Exterior layers of:
OSB sheeting,
1" R-6 R Max rigid insulation (taped),
R-6 Insultex House Wrap (taped)
And finished with stucco,
eliminate the dew point problem in a Zone-6?

I called Insultex and they recommended their product be installed over the rigid insulation

Thanks,
Dave

Asked By David Dunn | Jul 27 16
13 Answers

Insulating a raised floor over an old concrete slab

Hi, I have a house in Seattle. The back portion of the house has a 60 year old 600 square foot slab with approximately 2' deep footers. The ground slopes gently away from the foundation, and the roof overhangs each side by about 2-3'. Let's assume there is no gravel, sand, plastic, or insulation underneath the slab. There is no plastic or insulation on the exterior perimeter of the foundation either. The foundation perimeter vertically extends approximately 1/2"-1" above the slab. While the perimeter is level, the concrete slab is uneven, hence the 1/2"-1" inch variance.

Asked By Jo Lee | Jul 8 16
15 Answers

Exterior walls to meet code without gypsum?

Hello,

Maybe this has been discussed here. Feel free to link me to other threads that I haven't seen if this is fully covered elsewhere.

I'm not a fan of drywall. A quick rundown with no real surprises: it used to be cheaper; now it's not. It also takes plenty of work and more money to make it look nice. It's heavy but also very breakable. Even when you don't break it, it's messy. Etc, etc. I *am* a fan of 3/4 plywood, which is less breakable, more durable, and looks nice.

Asked By Minneapolis Disaster, 6B | Jul 22 16
7 Answers

Looking for design software recommendations

Hi -

I'm a new member and I'm looking for recommendations for relatively easy-to-use design software (I did try searching the site but didn't find anything discussing that). My first task will be a simple floor plan so I can ask the good folks here for advice on placing mini-splits. Further down the road, I'd like to be able to draw out details for roof and wall assemblies for the retrofits I hope to do. Any then maybe a tiny house (or at least a tiny shed) in the future.

Asked By Nickolas Van Kleeck | Jul 23 16
10 Answers

Bowed gable-end truss

Today we got 18/19 trusses set and somewhat braced, more to go on bracing.

The problem we ran into is that the gable and would meet the wall in the middle, but both ends were off the walls. The walls are straight and flat.

I pulled the gable down and snapped a chalk line along the bottom of the bottom chord, and found that the center was lower than the ends by a good 3/4".

Having never set a pre-buiilt gable truss, I would think that it would be nearly impossible to load the top chord enough during installation to push the bow out.

Asked By Mike M | Jul 24 16
6 Answers

Air space required for GE Geospring hybrid electric heat-pump water heater?

I'm interested in going to a heat pump water heater and looking at the GEH50DFEJSR geospring model. I see in the manual it says it needs a 10×10x7 room or louvre door or duct kit. I'm curious if a vented pass thru to a larger room works the same? Kinda like a cold air return. The room is 8x5.5x8 and would rather not put a louvre door up. Any recommendations? Anything else I should know before purchase?

Thanks so much!

Asked By Stephen Audretch | Jul 24 16
6 Answers

Preferred underlayment under metal on unvented roof?

Hi Everyone,
Need to make a final decision on which underlayment to use under a metal roof on an unvented roof system. The roof is currently built as follows: Beams on 5' centers; 1 1/2' T&G decking; 3/8" plywood diaphragm - seams taped; with TriBuilt granulated self adhering underlayment on top of the plywood.

Next I'll be screwing down 5 1/2"RayCore SIPS panels over heated space and framing boxes over the eaves covering everything with 5/8" CDX. Still looking at metal roof products but am zeroing in on a high seam (1 3/4") snap lock system. Roof pitch is 2/12.

Asked By Robert McKee | Jul 23 16
14 Answers

Unvented cathedral ceiling — insulating from above

I am re-doing my family room roof, which is a cathedral ceiling.

Since the roof is being re-shingled, I thought it a good time to remove the sheathing and lay down some closed cell foam. I have some unopened from a previous project

Everything I've read about unvented Cathedral ceilings talk about them drying from the inside. Obviously this can't happen if I'm spray in the closed cell foam onto the dry wall ceiling from above

The ceiling is 8" from drywall to plywood

Asked By Paul Buchkowski | Jun 25 16
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