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23 Answers

Mitsubishi mini split behaving very differently with external thermostat vs. without

I am able to monitor my home's electricity use and I always thought it was a little weird that my Mitsubishi FE18NA heat pump seemed to constantly be spiking up and down, considering that the whole idea of the inverter-driven compressor is that it can run smooth and steady... fast forward to yesterday when I received my MHK1 thermostat and hooked it up. Suddenly, the power usage was steady as a rock.

In Mechanicals | Asked By Nick Welch | Jan 6 15
21 Answers

Bug screen for rainscreen strapping...how wide to cut?

I'm a rookie with this. First time building a rainscreen. I've got my WBB on the house and would like to apply my 3/8 strapping to create and airgap.

I picked up a few hundred feet of 4' bug screen and I will first apply a layer top and bottom, then my strapping and then staple the bug screen on-top of the strapping making the air gap, hopefully, bug free.

In General questions | Asked By Mark Helmrich | Mar 18 15
10 Answers

Rigid foam interior or exterior of basement?

I live in zone 5 and am planning to start the concrete work next month. Right now I am at or just over budget without factoring in any rigid foam insulation for the basement.

In Green products and materials | Asked By Nicholas C | Apr 6 15
51 Answers

Dare to DIY a mini split install?

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

In Mechanicals | Asked By Justin Fink | Aug 22 13
3 Answers

Air seal large gap around light fixture box

I've made it to nearly my last electrical box in the attic that holds a light fixture. I've used fire caulk for all of them, but this last one has a big gap on one side, probably a half inch wide.

Caulk won't work, it just falls in. I'm thinking either fiberglass mesh and duct mastic or UL 181 foil tape.

I have both of the above, I could buy Great Stuff Fireblock foam but since that still ignites at 240 degrees I doubt that's the best idea.


In Energy efficiency and durability | Asked By Jeremy M | Apr 7 15
4 Answers

Is rigid foam as sheathing cheapest way to meet code?

I know: it depends.
I found GBA's detail of 3/4 rigid foam on the framing with 1/2" ply-osb sheathing on top. this gives an easy nailing surface for shingles. So if I can use diagonal bracing, (steel or 1 x4) and xps foam and cellulose this will give me R= 22.25. (Good for Zone 5) and also 18.5+ 3.75. My question is now I don't have to worry about the condensation point because my sheathing is outside my insulation?

In Building Code Questions | Asked By Keith McGuire | Apr 9 15
2 Answers

My client has an old 1840s home that never had any kind of vapor/water barrier

It is simply clapboard nailed to studs. He gutted the old plaster wall, and had the stud bays spray foamed directly onto the old clapboards. A few popped loose on the outside, so they re-nailed them.
My question is: will the foam retain moisture and cause the clapboards to rot, or will he be o.k.?

In General questions | Asked By roger steinbrink | Apr 9 15
7 Answers

Cold storage room in a basement and a heat-pump water heater

So I'm planning to have a cool storage type room in my basement for food. We are heating with mini-splits, and will have 9.3 kW of PV solar. I'm considering placing a 80 gal AO Smith hybrid heat pump water heater in the cool storage room. Figuring if it is going to cool a room anyways, I might as well make it a cool storage food room, and insulate the floor above so it doesn't cool the floor above.

How much space(sq ft) should I allow for room the heat pump will operate in so that it works effectively? It can also be tied into our general storage room too - to allow for more space.

In General questions | Asked By brad hardie | Apr 8 15
0 Answers

Cost of European materials going down?

With the Euro getting very weak has anyone noticed materials from Europe getting cheaper? We weren't planning on getting quotes for European windows/doors because of price, but I was thinking that with the Euro plunging, maybe some stuff could be purchased 25% cheaper than a couple years ago.

In Green products and materials | Asked By Kristopher Steege-Reimann | Apr 9 15
2 Answers

What is the best way to build a 2x8 exterior wall and achieve R-40?

I am building a house near Toronto, Ontario. Winters are cold, and we do see our share of -20 or colder weather. Summers have been somewhat hot in last couple of years.
My wall section looks like this right now from exterior to interior.
Stucco>1"rigid foam board (taped seems)>2x8 studs @ 16"OC>2" closed cell spray foam> R24 Batt>6mm poly>drywall.
I am worried about any moisture getting in the wall so that is why I am considering doing 1" rigid foam board from the outside and poly from the inside.
Can anyone tell me if they have done anything similar.

In Energy efficiency and durability | Asked By Slobo Urosevic | Apr 7 15
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