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6 Answers

Ducted heat-pump water heater

CZ 3A - Greenville, SC - mixed humid

I have been reviewing some studies online regarding ducting a heat pump water heater and think it might make sense in my new house. Here are the results from the study above, which assumes a garage located heat pump WH in central Florida:

Cooling Season Savings
Indoor to Indoor 3.8%
Outdoor to Indoor --1.2%

Heating Season Savings
Indoor to Indoor -5.9%
Outdoor to Indoor -17.5%

In Mechanicals | Asked By Norman Bunn | Oct 13 17
0 Answers

Capillary breaks and code

This is an offshoot from my previous question about choosing a product to use for the capillary break between the footer and the poured concrete foundation wall ...

In speaking with a rep from Tremco Sealants about using their Tremproof 250GC product for this purpose, he mentioned that we might want to check with our local building official to see if they have any problem with having a membrane in the cold joint between the footer and the wall.

Anybody ever heard of this being a problem?

In Building Code Questions | Asked By William Costello | Oct 16 17
3 Answers

Seal foam attic baffles at kneewall

I am installing the foam version of the attic ventilation baffle at my kneewalls so that I can blow in a good amount of cellulose. The online video from the manufacturer shows them simply hammer-stapling these along the trusses. Two things I notice, 1.) These things rattle like nothing else when air is coming from my vented soffit at the right speed/angle because there is nothing pinning these tight to the underside of my roof's OSB (ideally I'll have enough insulation to keep them somewhat tight) but I don't think it'll be *that* deep.

In Green products and materials | Asked By Nicholas C | Oct 13 17
5 Answers

What options for unvented, low-slope roof?

I am trying to determine what kind of roofing material to use on a low-slope (2.5/12), unventilated, shed roof. The roof will have closed cell insulation below the decking, so it must dry outward. But the typical materials for low-slope roofs, such as EPDM, are impermeable. I cannot take any approach that would add more than an inch total to the height of the roof, because it is a shed off a gable end of the house, and the roofline actually intersects the gable end soffit on one side. Other things that may matter: Zone 6, SE Exposure

In General questions | Asked By Fix it Again Sam | Oct 14 17
4 Answers

Tension tie when ledger is parallel to house joists

I am installing a small second floor balcony where the deck ledger runs parallel with the house joist. Is there any alternative to adding blocking between the house joist and installing those long tension ties that run from outside to the inside?
Seems like a place for heat to escape and a good place for water to condensate on the cold tie. I like the idea of the Simpson DTT1Z lateral load connectors but they say you cant use them when the joist run parallel to the deck ledger. Any alternative ideas?


In General questions | Asked By Michael Prisco | Oct 15 17
5 Answers

Can my outdoor minisplit unit benefit from a solar cover in harsh NY winters?

I am brainstorming a greenhouse type cover over my outdoor unit to keep it warmer in the winter to maximize its ability to heat. There are clear corrugated roof tiles at my local home store I am thinking of fashioning into a roof over the unit outside, facing South with possible partial sides. I am aware it needs air flow. My hope is to keep the outdoor unit warmer to avoid it getting too bogged down in the cold. It is a Fujitsu 15RSL3H made for extreme cold.

In General questions | Asked By PamNYWinters | Oct 14 17
13 Answers

Foam sandwich in Canada

Hi Martin,

I have a question about upgrading insulation in our home we're having built in Southern Ontario.

The "normal wall" the builder uses is 1" of XPS rigid insulation on outside, installed over OSB, on top of a 2*6" wall on filled with R18 fiberglass bat. Naturally, the whole thing is sealed on both sides, with tape on the XPS and poly sheeting on the inside.

In Energy efficiency and durability | Asked By User-6930437 | Oct 12 17
2 Answers

Does repair work have to follow current code?

It’s always about the water, and codes.

Our roof design is a mess, and our gutters are overwhelmed. I can identify most of the problems*, but since I currently live in a condo, I can’t just work on the exterior myself or hire a competent roofing and gutter contractor. I need to work through the condo association management. I have two questions.

In Building Code Questions | Asked By andrew c | Oct 14 17
5 Answers

Best choice for LED lighting?

LEDs are solid state lighting and much like microchips advanced in efficiency/performance quite rapidly.

In Energy efficiency and durability | Asked By J M | Oct 13 17
1 Answer

Sealing up gaps in OSB exterior sheathing before insulating stud cavities?

My OSB sheathing on the exterior side of my exterior walls has many a gaps varrying from 1/8" to 1/4" as the proper installation instructions require the sheathing to be gapped with a nail to allow expansion due to humidity changes.

So...I'm looking at these gaps (some rather large) and getting ready to stuff mineral wool in. Should I take any time now to a.) caulk or b.) spray foam these gaps? I have a decent house wrap over the sheathing of course but that doesn't stop everything.

In Green building techniques | Asked By Nicholas C | Oct 13 17
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