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7 Answers

Help with a new home and Isokern fireplaces

We live in a new home in Mansfield, Texas. Inside, we have 2 Isokern fireplaces with Eiklor Ultimate 5 log sets. When we run the fireplaces, they do seem to generate a strong smell we are concerned about. The smell in the master is worse than the living room. The home is air tight, energy efficient, and 1 story. The 3 ac units/furnaces do have Honeywell Fresh Air intakes. The fireplaces also have fresh air intakes. The logset installer says there are no gas leaks.

In Energy efficiency and durability | Asked By Austinl | Oct 15 17
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
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
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
5 Answers

Insulate basement ceiling?

Good morning everyone. Contractor is suggesting dense pack cellulose in conditioned basement (basement finishing job). Walls are insulated with cellulose/sprayfoam on concrete. Is this advisable? I've read not to insulate basement ceilings. Will it make it warmer in the winter? I'm in zone 6. This will obviously also help with sound dampening. Alternatives?

In Energy efficiency and durability | Asked By gi4ever | Oct 11 17
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