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18 Answers

Attic insulation quandary

Seeking advice on renovation plans for a 1910 house in ND - Zone 7.

HOUSE DETAILS:
- 2 1/2 stories above ground with full basement.
- 2nd story has 'sun porch' facing south.
- 2 layers of siding. Inner layer has lead paint (of course)
- Insulated in the 70's with formaldehyde foam, holes drilled through exterior to fill cavities.
- High efficiency propane furnace, forced air.
- 2 chimneys.
- 1st in middle of house used for original oil-burner furnace and water heater. Now used by wood fireplace in basement.

In GBA Pro help | Asked By Tim Lange | May 16 16
3 Answers

Asphalt shingle failure mechanisms

I looked at a 13 yr old house yesterday and found most of the asphalt shingles were severely curled and, obviously, needing replacement. The roof was unvented and insulated below the deck (i.e., no foam on top) but I don't know much more than that. The undersides of the rafters in a small storage area were covered with rigid foam. I was wondering what possible mechanisms (besides cheap shingles) could lead to such failure after a pretty short period of time. Thanks for any and all ideas.

In Energy efficiency and durability | Asked By Rob Shuman | Aug 17 16
2 Answers

I have a concrete floored, plaster walled bathtub alcove that I want to remodel into a curbless shower or wet room.

The condo building was built in 1959, and my unit was gutted by building management in 2014. The tub had been removed and drywall installed in the lower 18" of the alcove below the existing plaster which is on metal lath. (I have removed the drywall and replastered the area.) The alcove is 38" x 59" x 30 1/2" x 74"H. Red Guard has been suggested as has truck bed lining. Tiling the whole room also, with "curb" transferred to between bathroom floor and hall concrete floor (hall floor will remain polished concrete). I don't want a curb and I hate shower doors/enclosures.

In General questions | Asked By Genevieve Holubik | Aug 17 16
15 Answers

How can I stop in stop the infiltration of musty, humid air without tearing apart the wall of my historic home?

I live in a 100 year old house in New Jersey. Most of the time, the indoor air quality is fine, but on hot, humid summer days, especially after a rainstorm, the interior of the home is immediately overtaken by a musty, moldy --sometimes downright acrid--odor, and the humidity level jumps to about 80%. This come on very suddenly, and it vanishes just as quickly when the humidity level outside drops. I turn on my dehumidifier right away, which pulls gallons of water out of the air in several hours. This helps a bit, but is it not a real solution.

In General questions | Asked By Doug Schotland | Aug 12 16
10 Answers

Has anyone tried the Foobot Monitor?

Does anyone have experience with this indoor air quality monitor? Are there better alternatives for easily monitoring key indoor pollutants?

In General questions | Asked By Steve Knapp | Aug 8 16
12 Answers

Insulating floor joists, on stilts

Hi,

In GBA Pro help | Asked By Paul Huehmer | Aug 12 16
1 Answer

Spray foam my ridge vents and soffits closed?

Okay so I am investigating spray foam insulation for my garage. The most recent company I spoke with gave me a quote but also asked if I had a ridge vent. I said yes. They said they would also spray the vent closed because spray foam creates another atmosphere and we would not need it. Another atmosphere??

I don't understand why you would want to get rid of the ridge vent. Can someone shed some light on this topic, I am in the dark.

In GBA Pro help | Asked By Joe Overhaulin | Aug 17 16
62 Answers

Questioning my logic...GSHP, ASHP, radiant?

I'm in the planning/almost ready to break ground stage of a new home and I'm beginning to question my sanity when it comes to figuring out the right approach for heating & cooling.

The home is:
North end of Climate Zone 5
Main Floor: 1700 sq ft + 1000 sq ft garage, vaulted ceilings through much of it
2nd Floor: 1100 sq ft (2 bedrooms, 2 baths, living room) primarily over the garage
Basement: 1700 sq ft, partial walkout + 1000 sq ft shop under the garage (separated from the rest of the basement)

Walls: R30+ (2x6, 2" XPS outside, 2lb SPF for sealing + 1/2lb SPF for cavity fill)

In Mechanicals | Asked By Dave De C | Jul 16 16
1 Answer

Can you use Blueskin without a drain plane?

The architect for my client's home has specified Blueskin WRB under untreated Alaskan Yellow Cedar with no drain plane. The house is facing the ocean just 200 feet away from the water on the central coast of California. In our mild climate we can often get away with building assemblies that other climates can't, but the ocean is relentless on building materials.

In Energy efficiency and durability | Asked By Steven Jungerberg | Aug 17 16
3 Answers

Venting a combined basement bathroom / laundry room into existing 4" vent / drain stack

I've had a few quotes for installing a new 4 piece combined basement bathroom / laundry room (dryer, shower sink toilet) as apart of getting our basement finished.

Currently the main 4" stack serves as a combined vent / drain for a 3 piece washroom (2nd story), and as a drain for a (1st story water closet - 2 piece, that is separately vented with a 2" vent through the roof)

In Building Code Questions | Asked By Mike Tew | Aug 16 16
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