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2 Answers

Excessive Moisture in Minnesota

We live Northwest of Minneapolis (6a/boardering on 7a) in a 2 story + full basement house (2,500 sqft) built in 1998 (2x6 walls/R19 fiberglass, vinyl siding, Tyvec, Built Right Sheathing, so-so all vinyl windows) that has winter moisture problems (condensation on windows, mold, freezing). During our pre-sale inspection, we noticed moisture on the 2nd floor windows and found that two upstairs bath fans were not attached to bottom of the roof deck, the insulated ducts/flanges were laying in the insulation (thankfully the flanges were taped closed).

Asked By Z Lessin | Dec 10 16
1 Answer

How do I get rid of A LARGE AMOUNT of attic moisture

I bought the house I grew up in that was built in 1952 24x30. 1972 an addition was added making it L shaped. I had central AC installed 2016. The installer did a terrible job of installing the metal boots in each room and there was no stopping airflow around them, not properly insulated, and insulation was not packed back around them. For a year and a few months this was the condition. Then my daughter moved in and was washing cloths and hanging whole loads of laundry in the house. I also had house pressure washed.

Asked By Scott Hill | Dec 10 16
2 Answers

I need insulation help in Baltimore

I am in the process of rehabbing a 1904 house in Baltimore and getting to the second floor (the third floor is finally complete). My overall plan is to strip the plaster and lath so I can use spray-in foam to achieve air sealing and at least a respectable R-value. Closed-cell has some advantages (R-value, air sealing) but maybe adds a risk of moisture problems. Open-cell put in to a depth of 5.5 inches would give me R-18 or so, which is far above what's there now, but perhaps the air sealing isn't as good. And I want to understand their fire resistance and sound insulating qualities.

Asked By David Soderblom | Dec 10 16
6 Answers

Lunos e2 ductless HRV system vs. ducted system

I am building a net zero house, 2000 SF, 2 stories. Can you tell me the pros and cons of the Lunos e2 ductless HRV system vs. a ducted system? The rep told me that 3 pairs of the Lunos e2 would be about right.

Asked By Courtney McCracken | Dec 8 16
2 Answers

I recently had a metal roof installed on my house

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 [to the shingles].

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
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