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1 Answer

I recently had a metal roof installed on my house and am wondering if it was installed properly. The roof was installed over two layers of shingles. The roof is over 20 years old with damaged and raised shingles. The contractor applied the metal directly

I am also concerned about the exposed metal fasteners. There is about a quarter in gap between the metal panels and the metal fasteners.

Asked By Linda DuBois | Dec 10 16
1 Answer

Incorrect plumbing joint fix for basement bathroom install

5 years ago we had our main sewer line replaced with PVC line which 90s into our main 4" stack. City and plumber failed to put in a 90 y / floor drain and we we're told we would be fine with basement bathroom install. More recently, the driveway has been redone. Present day, 2 plumbers have told us that due to proximity of the joint to the wall, they cannot guarantee cracking will not happen on the short run of 4" that goes out the straight out from the 90. There is an 8" fail-safe as the pipe is under the foundation.

Asked By Mike Tew | Dec 10 16
2 Answers

Uninsulated slab and hardwood flooring

I'm renovating a small outbuilding on a farm (15' x 15'), which has slab on grade foundation. The slab is sitting on crushed stone but has no vapor barrier underneath. I have put a 10 mil poly sheet on top of the slab, and 2x4 joists (sleepers) on top of the poly sheet.

My plan was to now spray foam insulate (about 2" - 3") on top of the poly sheet, then install subfloor and then hardwood.

Asked By Brian Greene | Dec 9 16
0 Answers

I'm not able to add an article to my GBA project

Trying to add articles to my GBA that are not transferring - are there restrictions?

Asked By Kris Burkett | Dec 10 16
16 Answers

Rigid foam minimum for 2x8 stud wall

Zone 5 - helping with a wall design. They are using 2x8s for studs to fit in R-30 mineral wool. I am suggesting rigid foam, EPS or XPS, but I have only read that 2x6 wall needs R-7.5 But, this is a 2x8 wall, and I don't think R30 is traditional. So Will 2" of XPS or EPS be sufficient? Don't really want to have to go with two sheets and achieve 2.5" of rigid foam if 2" is sufficient with R30 mineral wool on the interior.

Is there any way to make 2" work? Such as a smart membrane installed before drywall?

Asked By Nicholas C | Dec 9 16
76 Answers

Sun Bandit solar water heater

Hello. I was reading the article by Martin Holladay entitled "Solar Thermal is Really, Really Dead" and enjoyed the discussions going back and forth on the topic of solar water heating methods. I am planning on building a small 600sq' SIP cabin in the area of Nelson BC (climate zone 6) next year and I found this product listed as being one of the most efficient for heating domestic hot water on the Canada Energy Guide site. It says it can also be used for space heating via a radiant floor system or perhaps radiators.


Asked By Scott Wilson | Oct 21 16
10 Answers

Double interior rock wool

Working on plans for my next home. After lots of research on here and others I am considering the following wall assembly. From the exterior... wood siding, tar paper, 1/2" plywood with taped joints, 2x4 ,16 on center wall stud with roxul, uniterupted layer of 1 1/2" comfort board, layer of a variable perm vapor barrier (taped seams and such), then a layer of 2x3 installed 2 ft. on center as battens for electrical with shallow boxes , second layer of comfort board fit between the battens, drywall finish. I am in zone 5 in northern ct.

Asked By scott mangold | Dec 8 16
7 Answers

Tiny home heat pump (Mitsubishi or Fujitsu) for a mostly empty house

I am in the process of renovating a 1-level 470 sq ft basement walkout condo in Kittery, ME. It has two floors above it. I've consulted a contractor, and don't agree with their suggestion for a mini split. So, I've started doing research!

Asked By Kate Harris | Dec 9 16
10 Answers

Does anyone have experience with the Rheem Prestige heat-pump water heater?

I was excited about using the Sanden CO2 HPWH, but communication with the company was very hit or miss. The local installer they referred me to was very responsive and helpful with technical information. He gave me a quote for $5,900 installed. This was for a 43 gallon tank (the 83 gallon tank, oddly enough, would've been $6,100 installed). Because of the poor communication, and the cost, we had to move on.

Asked By Eric Whetzel | Dec 8 16
3 Answers

What capacity rating should be used for sizing ductless heat pump?

The easily obtainable heating capacity information for ductless heat pumps are generally listed as Btu/h at 47 degrees and Btu/h at 17 degrees. These don't appear to line up with the expanded capacity charts which can (sometimes) be found with some digging on manufacturers websites. Let's look at the Fujitsue ASU9RLS3:

It's capacity is readily reported as:
7,0000 Btu/h @ 17 degrees
12,000 Btu/h @ 47 degrees

However, if I look up the expanded heating capacity chart, it reports the Total Capacity as (assuming 70 degrees indoor temperature):

Asked By James Reider | Dec 9 16
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