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3 Answers

They didn't completely hook the cold air return on my furnace. Is that OK? What could happen?

can just using indoor instead of fresh outside air cause any problems?

In Mechanicals | Asked By Roger Blankenship II | Feb 1 16
1 Answer

Moisture accumulating before vapor barrier installed.

I'm in zone 7A and built an attached garage this fall: in slab heat, 2X6 walls, Rex wrap and OSB sheeting. The in floor heat got hooked up and turned on the beginning of January at the same time I began insulating the walls with unfaced fiberglass batts and faced batts in the ceiling.

Before I got poly vapor barrier up on the inside, there was a large amount of moisture (it was frost when it was cold outside) accumulating on the inside of the sheeting behind the batts.

In General questions | Asked By Neil Knutson | Feb 3 16
2 Answers

What is the ideal choice of cladding over OSB-Sheathed SIPs?

Hey Martin,

I find myself in a situation similar to one discussed here in the past regarding putting masonry, i.e. thin veneer, over SIPs. The original question was regarding which WRB to use. However for me, unlike the pervious poster, I have time to make course corrections. You previously said this was a "particular risky combination." I would like to know your recommendation of cladding over SIPs if stone veneer is not a good choice.

I live in Maryland, so we get plenty of rain. Just FYI.

William Lohr

In Green building techniques | Asked By William Lohr | Feb 1 16
1 Answer

Thermoarcilla? Termoarcilla? Thermal Clay?

I've been working with a Spanish carpenter who told me that a lot of walls in Spain are being built with Thermal Clay, which I guess is the translation of Termoarcilla. I have had greast difficulty fining much information online in English (sorry my Spanish is not so good).

Here is some information: http://bloquetermoarcilla.es/en/productos-termoarcilla.php

In Green products and materials | Asked By E T | Feb 3 16
1 Answer

Chinese Split Heat Pump Water Heaters

Sanden is getting a lot of attention due to their Eco-Cute split heat pump water heater using CO2 refrigerant.

In China though there seem to be many manufacturers making split heat pump water heaters using Japanese compressors (albeit with more common refrigerants). On alibaba.com or made-in-china.com do a search for "heat pump water heater" or "evi heat pump" or "twin rotary heat pump" and the options seem to be endless.

In Mechanicals | Asked By Osman Anwer | Feb 3 16
3 Answers

Not sure what's going on with this foundation...

This is not my house so questions will take a bit to ask the owner and post, but as i understand it its a century old house near Toronto Ontario, the original basement was concrete but only about half way down, (shown by the hard to see cantilevered foundation) but the basement was dug out to full height and the CMU was installed inside of the original foundation.
The question is what is causing the cracking (is the house shifting, rising or the foundation falling) and how best to deal with it?

In General questions | Asked By Alan B | Feb 6 16
2 Answers

What coolant that can be applied to an existing metal roof? Cost a fortune to cool building.

Trying to cool my building. 15 yr old metal building for retail business.

In Energy efficiency and durability | Asked By amelia quinney | Feb 7 16
9 Answers

Plywood as exterior cladding

We are in the master planning phase of building a modern house in the PNW. We are in the Marine zone 4c. We would like a clean exterior that fades into the landscape and do not want a house that looks like it doesn't belong on the land. Considering this, I have a question.

Why isn't stained plywood used as exterior cladding? Will it work if we have good roof overhangs and a 1" ventilated rain screen? We are researching this as we would like an organic looking exterior that is clean. It seems like this practice is prevalent in Australia and NZ but not here in the US.

In General questions | Asked By Jay Raja | Feb 6 16
1 Answer

Are back flow dampers needed for intake on ERV?

I am installing a couple of the panasonic spot ERV's. One of them will use two matching wall exhaust hoods with the the flapper removed on one for the intake. Should I install a back flow damper just inside of this? Or would this be pointless because any breeze blowing in the duct would be strong enough to open it?

On the second ERV I am installing one of Panasonic's "Y" combiners that combine both 4" ducts to one 5"duct and intake/exhaust hood. This is what it looks like.

In Mechanicals | Asked By Kail Zuschlag | Feb 5 16
1 Answer

Bathroom ceiling

I am going to be installing t&g pine (sealed all 4 sides and ends) on a bathroom ceiling. The ceiling is below an unvented roof and conditioned attic space (8" closed cell foam in rafter bays). Climate zone 8.

I want to know if I should install the t&g directly to the framing members or to put up drywall first. I already have an ignition barrier over the foam. Will drywall just be a surface for mold and mildew? I have a Panasonic whisper green vent fan and a window in this 72sq ft bathroom.


In GBA Pro help | Asked By Jon Patrick | Feb 6 16
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