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11 Answers

Drainwater heat recovery questions

Hello, I've been reading some things on drainwater heat recovery and came upon this article: http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/toronto-passi...

In it, Lyndon Than says, "Leave at least a 12-inch run of straight drain pipe above the exchanger to smooth out the flow."

How critical is that? I don't have.much room to work with -- about 36" in total. I could likely get a 30" unit in that space, but if the 12" above is necessary, it wouldn't be worth the trouble.

Asked By Calum Wilde | Jun 26 17
8 Answers

Which ductless minisplit?

Zone 4 climate - 735 sqft - R25 walls - R40 roof - R5 windows - very tight ICF home - glazing is minimal with a low SHGC

A Manual J was done and it showed a 1 ton unit would heat/cool the home. I'm undecided if I should bump up to a 1.5 ton unit? Here are my options:

A - DuctlessAire Mini-Split - 1.5 ton - 21.0 SEER - $1,400
B - DuctlessAire Mini-Split - 1 ton - 21.5 SEER $1,060

Is it worth the extra $340 to up-size to the 1.5 ton unit?

Asked By Peter L | Jun 22 17
3 Answers

Insulation for my basement walls

Hey,

Was wondering if anyone could recommend a type or place to get rigid foam for my basement walls.

The price of rigid foam insulation seems to have skyrocketed. I have 8' ceilings in my basement and about 70 linear feet of concrete wall to insulate. That's 35 2x8 sheets of dow XPS which at $42 a piece is $1600-1700 for r10. Throw Roxul on top of that to get to r24 and now I'm looking at $2500 for just insulation.

Asked By Tim-X | Jun 26 17
6 Answers

Does the insulation on this wall make sense?

I live in Madison WI and am renovating my 1927 house. I have stripped the outer walls to the studs and shiplap and have been trying to figure out the best insulation scheme. The constraints are 1. in Madison they really want plastic on the inside, and 2. because of architectural details I can't put more than 1 inch rigid insulation on the outside.

Asked By user-6832947 | Jun 27 17
5 Answers

What is minisplit short cycling? Turndown?

I understand that a "somewhat" oversized mini split will generally run at a more efficient rate, as opposed to an undersized mini split, which will run full-out, and therefore be less efficient. It sounds as if the problems with oversized mini splits would be 1) wasted money on oversize equipment, and 2) decreased dehumidification, due to the equipment not running enough. Am I about right, so far?

Asked By Ben Rush | Jun 25 17
4 Answers

Insulating a 1930s home with foam and fiberglass

Hello,

I have gutted my bathroom of my 1930 cape cod and am looking to insulate from the inside.

I live in zone 5a, upstate NY
The house exterior is brick, with a gap between the brick and the exterior sheathing ( which is 8 inch boards)

My thoughts are this

Asked By Jason A | Jun 26 17
1 Answer

What type of sealant?

Hi,
I am retrofitting a window into a 1985 wood framed stucco house in Southern California. It has something like a grade D paper behind the stucco. I am using 15# felt to repair the damaged paper around the window opening. The window will be set on to the 15# felt. The flashed with a peek & stick flashing. So I need a tube type sealant that will stick 15# felt to a Anderson 100 FIBREX window frame.
What type of sealant should I use to set the window to the 15# felt?

Asked By Tim R | Jun 27 17
5 Answers

Concrete slab reinforcement: M100 vs. F100 fibers: finish and strength

My concrete contractor has 2 fiber choices for the slab pours : M100 and F100 from BASF. Both are polypropylene fibers, the difference is the size.

Officially M100 is only to be used to prevent shrinkage cracking. Unofficially it has been used (with apparent success) to replace light wire mesh in slabs poured in Southern Ontario. Concrete contractors prefer it when a smooth finish is requested as the extra fine fibers make the slab easier to finish.

F100 is a larger fiber, that is approved by BASF to replace light gauge wire mesh. There is no question this is the robust choice.

Asked By Mai Tai | Jun 25 17
3 Answers

Baffles and blocking at eaves (retrofit)

When doing a retrofit application in an attic we typically install 2 baffles for each soffit vent, and then block off below the baffle in order to prevent insulation from falling into the eaves. All other eaves are also blocked with scrap fiberglass so that insulation does not fill the eave.
I am having difficulty explaining to my installers why it is necessary to block the eaves that don't need baffles, or in a home where there are no soffit vents. any good articles etc. to recommend?

Thanks,
Jeff

Asked By Jeff Classen | Jun 26 17
8 Answers

Is Thoroseal good for the capillary break on footing?

I'm looking for something that can be applied to green concrete (7 days after pour ok) that would provide the capillary break on top of the footing before the foundation wall is poured. Is Super Thoroseal (or regular Thoroseal or Thoroseal foundation coating) going to work?
Thanks!

Asked By e c | Sep 15 14
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