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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.

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?

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.

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.

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.

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.


Asked By Jon Patrick | Feb 6 16
1 Answer

How to fix shoddy garage addition?

This past summer I bought a house in SE Michigan (Zone 5a) that was built in 1978; we had an energy audit done and the auditor alerted me to a host of issues included that when they built out into the garage to expand the kitchen & laundry room they left the top of the walls and ceiling open to the unheated garage.

My question is what is the best way to go about fixing this issue from a cost standpoint. I'm concerned if I just seal the top off the wall with XPS & Great Stuff that condensation will collect since there will be colder air inside the wall from the uninstalled garage.

Asked By Patrick B | Feb 6 16
2 Answers

Fireplace insert or glass doors + outside air intake?

I have a rather large fireplace that can clear the house of all heat, so I am never really using it. Would be nice to make it functional source of heat and have it as a backup for those times in winter we lose power or when minisplits can't cover entire heating load.

Question: do I have to go the expensive fireplace insert + outside air supply route, or going with the proper glass doors + outside air supply would give me good return on investment?

Asked By Apollo S | Feb 6 16
1 Answer

Concrete sealer needed before finishing basement?

I live in a home in Zone 5a that was built in 1978 with a poured concrete basement, our house sits relatively high with ground sloping away from the foundation. We are planning on finishing out basement it with XPS and then metal framing/drywall.

Asked By Patrick B | Feb 6 16
1 Answer

Does plywood flooring have to be removed before adding insulation?

My attic currently has a settled 8" of blow in insulation. I am adding more batts at an R-30 value. Previous owners installed plywood on joists for storage and nailed it every 6". Can the batts I'm addind be placed over plywood or must it be removed?

Asked By Dan Dadario | Feb 6 16
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