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5 Answers

Retrofit flood-resistant wall assembly

Proposed Wall Details:
- 2x4 treated bottom plate, untreated 2x4 framing, 1/2" exterior plywood sheathing covered with building paper and Hardi Plank siding on the exterior (No rain screed).
- Bottom of stud cavity (First 12" to 18") insulated with closed cell spay foam, the balance of the wall insulated with fiberglass of rock wool.
- Bottom ( First 12" to 18") of interior finished with PVC wainscoting or other waterproof material. the balance of the interior wall finished with 1/2" drywall..

In Energy efficiency and durability | Asked By Anthony Swoope | Dec 8 17
24 Answers

Marine Zone 4 — Wall insulation — addition

Zone: Marine 4
Location: Seattle, WA
House Built: 1915
Square footage: 900 ft2 single story with 900 ft2 finished basement.
Wall height over basement: 12 ft
Current siding: Cedar, Paint in poor condition.
Insulation: not much, some fiberglass bat stuffed in nooks and crannies as they opened walls in the past. And dirty so there is plenty of air gaps.

GOAL: Comfort

In Plans Review | Asked By User-6933356 | Oct 11 17
8 Answers

Boral--Proper installation on vertical siding

We are building an addition in Western Pennsylvania. The plans called for cedar siding but a change order now specifies Boral Bevel siding installed vertically over 1/2 inch plywood +Tyvek House Wrap + 1 inch XPS T/G foam insulation on the outside. All the Boral literature indicates installing vertical siding on horizontal drainable furring like CoraVent. The architect talked to the Boral rep and she stated that it was OK to install directly on the wall without furring because Boral won't swell or rot. Any suggestions?

In GBA Pro help | Asked By Brian Magan | Dec 8 17
2 Answers

Cycle Stop Valves

Has anyone looked in to Cycle Stop Valves for residential use? Do the motors really reduce their power consumption when throttled? How does the use of a pressure reducing valve effect the pump and motor cooling? Any other side effects I haven't considered?

Thanks guys.

In Mechanicals | Asked By Calum Wilde | Dec 7 17
17 Answers

Does anyone have any experience with ductless splits for very low inside temperatures (3 degrees C)?

We have a church in the Ottawa Ontario area (zone 6A). The church is only occupied for about 1 hour a week. We are using a very old oil fired FA furnace.(about 80% eff. 164K BTU input). I did some measurements last winter when the outside temperature was -20C. The furnace ran for about 5 minutes each hour to maintain 3 C inside. Would I be able to use a ductless split to maintain the inside temperature during the week and use the oil fired system to bring the temperature up for Sunday morning?

In Green building techniques | Asked By SanfordAndSon | Dec 4 17
2 Answers

Spray foam application in neighbors’ home

We live in a new construction neighborhood, and the home being built next door is about ready to have insulation installed. The homeowners next door have elected to use spray foam insulation. Based on my research on this product when our construction was ongoing, I recall that there are dangers in exposure to this product until it is cured (we ended up just using fiberglass batts, mostly because the builder charged an extra fee for the spray foam).

In General questions | Asked By Brian Jackson | Dec 7 17
4 Answers

Recommended sheathing tape width?

How wide should sheathing tape be to provide a quality air seal on OSB in CZ 3A? I am looking at 3M 8067, but am open to other options.


In Energy efficiency and durability | Asked By Norman Bunn | Dec 5 17
4 Answers

Rain Screen material options

I see a lot of different products commercially available to create a rain screen - basically a gap between the external sheathing and the siding. But why would I not do something simple/cheap like ripping 1/4"-1/2" pressure-treated plywood into ~2" wide strips, and nailing those up in line with my studs for my rain screen spacers? What benefits do I gain from buying a more complicated product? Separately, I still need to think through the correct kind of "bug filter" at the bottom - this is where a commercial product makes sense to me - I appreciate any recommendations on that.

In Green products and materials | Asked By MarkM3 | Dec 6 17
3 Answers

Replacing double-paned window glass

Old window is Willmar Window uPVC, 70/32, installed horizontally in 2001. The seal failed in 2016 on the lower left hand side.

We replaced only the window glass in the summer of 2017. Synergy Solarban 70XL

After a recent winter storm, the frame of the Willmar seems not to support the new window glass.

In Energy efficiency and durability | Asked By Carolelm | Dec 5 17
2 Answers

Can I remove a vent-free gas wall heater or should it be done by a professional?

I was reading your piece on Vent free heaters. The home I purchased a earlier this year has a vent free heater, installed by the previous owner. I have never used it out of fear and want to know is it best to have it removed or should I just never turn it on? If removal is the answer should it be done by a professional?

Thank you for your time.

In General questions | Asked By Smilingbrook | Dec 7 17
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