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0 Answers

Extended Plate and Beam

I would love to hear the pros and the cons of the extended plate and beam construction. I’m in zone 3.

In Energy efficiency and durability | Asked By Eric Chandler | Jan 12 18
14 Answers

What have you used for siding/trim/etc?

I am trying to decide on the healthiest product to use for the exterior. I know it won't really affect indoor air quality if our house is air tight (which I hope it is), but I just really want to chose the product that is the least risky in terms of health. Hardie Board makes me leary because of the Silica. I know it is really only harmful when being cut and installed, but it just makes me nervous. What if we need to repair it or remove it and reinstall? I don't really want to worry about silica dust being everywhere with kids.

In Green products and materials | Asked By Carolyn Farrow | Jan 7 16
3 Answers

Swapping in open-cell for cellulose


I appear to live in an area with not too many contractors who do dense pack cellulose in new construction. (A fair number of guys to wet spray.) I'm looking to build a double wall house. While I've got a lead on dense pack installers, there are a lot more guys who are suggesting water-blown open cell.

Is water-blown open cell insulation is acceptable in a Zone 5, 12" double wall cavity with an external plywood air barrier. Are there hygrothermal downsides to this subsititution, other than the change in R-value/inch?

In Energy efficiency and durability | Asked By John Ranson | Jan 11 18
16 Answers

Sizing a mini split heat pump question

In my climate, both heating and air conditioning is important, though heating is much more dominant here in the mountains. I've completed a Manual J for heating a home we will be building this year.

Our outdoor 99% design temp is 16 F, giving us a heating load of 16,350 BTU at that temp. Our heating load at 47 F is around 7,000 BTU, and the few nights we drop to 5 F would be 19,700. We'll have backup heat with a propane stove, so I'm not too worried about severe cold. I don't believe I need a hyper heat mini split.

In Energy efficiency and durability | Asked By Debra | Jan 8 18
5 Answers

Bubbling drywall seams beneath foam cathedral ceiling

I see some bubbling along two seams in my cathedral ceiling drywall and would like to determine the likely culprit. The ceiling showed no indications of issues for more than one year.

The drywall isn't sealed perfectly, this is my best guess. Yes, I have a few can lights and an exposed ridge beam that could be better sealed. Or maybe it's the roof, finding it's way through.

The ceiling is unvented, witch 6" of cut-n-cobble rigid foam, followed by 3 to 4 inches of closed-cell spray foam.

In General questions | Asked By Blutowski | Jan 11 18
6 Answers

Insulation strategy

I've attached pictures of a house we are currently designing and planning to build in the spring. We are in zone 6.

In Energy efficiency and durability | Asked By Jeffrey O'Donnell | Jan 12 18
15 Answers

Frost buildup in wall cavity in unfinished house

Happy New year. My wife and I are totally rebuilding our house, starting from the foundation up. We are living in it while completing interior work. We live at 1600 feet in central

In Energy efficiency and durability | Asked By Dpcvt | Jan 6 18
5 Answers

Flow Rated Fans - How Do They Regulate?

Bathroom-style fans like Panasonic's WhisperGreen units regulate their speed to ensure consistent airflow as restriction varies downstream. Does anyone know how this works exactly? I'm assuming it would use a pressure sensor on the exit side of the fan and have programmed speed values for differing levels of restriction, but that's just me guessing.

In Mechanicals | Asked By Lance Peters | Jan 8 18
1 Answer

Another selection criterion for mini-splits

I've looked at many close cousins in the mini split market and have observed a few interesting facts, some of which might affect which unit I choose. 1. Modulation range this is expressed on the data sheet by a minimum and maximum capacity @ 70f. Observation, there appear to be several "classes"

In Energy efficiency and durability | Asked By Jerry Liebler | Jan 12 18
8 Answers

Heating a tent

I use foil-faced bubble wrap inside a "Wildernest." A "Wildernest" is a tent that pops up out of my pickup truck topper.

I heat this ~200 ft³ area with a propane radiant heater. My thought was the foil would bounce the heat in to objects that could absorb it. Also this is a tent, so the R-1 value is appreciated.

The bubble wrap also folds up with the tent when the tent is stored inside the topper.

In General questions | Asked By Martin Holladay | Jan 10 18
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