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1 Answer

Heating and cooling Load Calculations


So the plans for my house are complete and now I need to get load calculations done, anyone know of any good company's in Southern Ontario( Toronto area).

Would like to use Mini splits, the house is going to be tight and well insulated. So hopefully I can find someone that can understand my needs and not just try to sell over-sized unit.

With determining R-value of a wall that will have 6" of Polyiso on the outside of a 2x4 stud wall filled with R14 Roxul, what rating would I use on the Polyiso knowing the outer will de-rate some.?

Asked By Dave B | Jun 28 17
0 Answers

Best Solar Panel

I am looking for affordable solar panel for home. I have found these on this site http://interiorsherpa.com/best-solar-panels/. Can anyone can check these and guide to purchase best and affordable solar panels for my home.


Asked By toran | Jun 28 17
4 Answers

Two minisplits in one room

I just had my mini split system installed. I got multiple opinions from the installation contractor regarding the number of indoor units in one room. There is the setup:

Asked By Bryan56 | Jun 27 17
3 Answers

ERV odour?

I've read of issues of some ERV units having a "plasticky" stink, as discussed on some austrian and german forums, which affects certain batches of enthalpy heat exchangers made by paul, and used by zehnder and helios among others.

But that aside, how would an ERV cope with removing odours made by regular but moderte cooking?

For example, we stir fry vegetables and grill meat maybe twice a week rest of the time it's just pasta or eggs or some soups.

Equivalent of climate zone 4 (~philladelphia), 3 people in a new 2200sqft house.

Asked By davor radman | Jun 28 17
2 Answers

Non-electric Fresh Air vents

I am considering using the Lunos type of ventilation fans which seem to require electricity all the time in order to work. Has anyone used these non-electric ventilation devices?


This is for an off grid cabin run on PV panels.

Asked By Scott Wilson | Jun 27 17
2 Answers

Most efficient HRV/ERV product for small airtight space, all seasons?

Hi, I'm building a mobile office using a heavily-insulated, airtight 20-foot shipping container. All heating/cooling is via a single heat pump powered by batteries and 2000 watts of solar panels on the roof; this will have no windows. It will be used in New England, so cold winters and hot summers.

I wanted to know what the most efficient heat recovery ventilation would be for such a small space, that I can actually buy in the US.

So far the best candidates I've found are:

Asked By EfficiencyDude | Jun 28 17
1 Answer

Structural masonry joist pocket retrofit

I am doing a complete retrofit of a 1910 masonry 4-square. The foundation is rubble with structural brick wythes x3 for the walls. The rubble foundation terminates about 36" above grade at its lowest point. At this point, the 1st floor joists are pocketed into the brick work. There is approximately 4" of rubble ledge then 5" or so of brick penetration for the joist pocket.

Asked By Sam Onuska | Jun 27 17
8 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
3 Answers

Panasonic WhisperValue DC fan and TRB transfer box - anyone using these in the field yet?

For a while now I've been considering different ideas to distribute the air from my mini split to bedrooms when the doors are closed. I just noticed that Panasonic recently came out with a new DC motor version of their 3 3/8" deep WhisperValue fan, with selectable speeds (50/80/100CFM) and pretty low sone (noise) ratings.

They also make this transfer box that's designed to fit this fan (google Panasonic TRB -- I can't link anything or the spam filter gets me).

Asked By Nick Welch | Jun 27 17
5 Answers

What type of sealant?

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
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