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4 Answers

What type of tape is recommended for poly seams under basement slab?

Looking for recommendations for the best tape to use on poly seams under basement slabs. Can the same tape be used on polystyrene foam board if it is used under the slab?

In General questions | Asked By Kim Hibbs | Feb 12 11
45 Answers

ERV choice

So looking at ERV for my build, and comparing models. Want something efficient, but not crazy $$$.

The house hopefully will be tight and well it is on the larger side.
Main floor is 2275sq' walk-out basement is 1880sq' of finished area. (including unfinished area it is 2275 also)
So 4155sq' of living area, currently only 2 people and 2 large dogs.
Will have it's own dedicated duct work (heating/ac hopefully will be mini-splits)

Zone 6 (20 miles SW of Peterborough,ON)

I've looked at the following models

In Mechanicals | Asked By Dave B | Mar 12 18
1 Answer

Air & Moisture Barrier with unconditioned Crawl Space

North Idaho

Unconditioned Crawl Space
Hydronic Floors
Only Power Source Available is Electric.
Fiberglass Insulation between Floor Joists.
A/C Ducting with Insulation in Crawl Space striped tight against Floor Joists.

Create and air & Vapor Barrier between Crawl Space and underside of floor.
Reduce thermal bridge from Floor Joists.
And, most important reduce heating costs.

Based on above what is best method to achieve goals?

In Energy efficiency and durability | Asked By North Idaho Guy | Mar 14 18
9 Answers

Should I install door to separate main floor from basement?

Good morning everyone. Wondering if we should place door at bottom of stairway (top just wouldn't work) of raised ranch home. House is new and we're finishing our basement. Both floors will have conditioned space with supplies, returns, etc. Will this help the basement area maintain temp/humidity better? Or is this a fool's errand? Thanks.

In Energy efficiency and durability | Asked By gi4ever | Mar 14 18
0 Answers

HRV Core Material

While researching HRV units I noticed that some have a Polypropylene Core and others an aluminum core, which one is better?

More Efficient:
More Durable


In Mechanicals | Asked By Dlauffenburger | Mar 14 18
6 Answers

Zone 7 garage wall insulation

Zone 7
1000sf detached garage
No hvac at present, will be added and run intermittently.
1960's build

Current assembly:
Steel siding
~1/4" rigid exterior sheeting
Shiplap (possibly salvaged)
2x4 @ 16"

The shiplap has large gaps (up to 1x12 inches). Short of spray foaming/caulking the shiplap prior to putting bat insulation in I do not see any practical way to seal it. Is there any reason not to just go with R-13 batt insulation (faced or unfaced) with a vapor barrier? Interior will be unfinished.

Attic will be sealed and ~R-60 cellulose.

In Energy efficiency and durability | Asked By DavidJ7 | Mar 13 18
26 Answers

Insulation upgrades

Hi Everyone.

Thank you in advance for your feedback, you have all been so helpful.

Zone 5A (coastal Mass) house.

I have an older 3200 sq ft home with a mix of well-pointed fieldstone foundation and poured concrete. The 1000 sq ft attic is currently air-sealed in most places, and has a mix of fiberglass batts and cellulose for about R-30. I have 10 recessed lights in attic, which have the LED airtight retrofits with gaskets, but are not covered in cellulose. The recessed fixtures are IC-rated. The remainder of the home has vented cathedral ceilings (sigh).

In Energy efficiency and durability | Asked By Justin Brown | Jan 22 18
4 Answers

Staple-up hydronic heating: air cavity or aluminium exchanger?

I'm getting ready to install the radiant tubing in the floors (staple up from the bottom to the sub floor in between the joist bays). I was planning on getting aluminium heat exchangers, as I imagine they are more efficient for heat transfer. However, I don't like the added cost of the material and labour. I spoke with my local Upanor rep, and he mentioned that without them, I'd need to do an air cavity at the top of the floor joist bay.

In Energy efficiency and durability | Asked By Jamie B | Mar 13 18
18 Answers

Radiant for comfort, not heating

I put radiant tubes under my slab when I built my house, there is 5 or 6 loops around 200'.

I want to install something, preferably electric, to warm my (wifes) feet, but not toss a lot of heat and disrupt how my current propane furnace operates, something simple. Just an expensive foot warmer, is that possible? Just under 2000 sf, I wouldnt have to, and may not want to use all the zones, but 1000 sf at a minimum. Thanks.

In General questions | Asked By T Carlson | Mar 8 18
2 Answers

Insulation Against Concrete and AAC Wall

Hi all; with the help of the answers to my previous question (thanks!!) We've attached 3" of XPS and EPS foam against the interior of my foundation walls. We used a combination of glue and screws/washers to hold it against the walls. All told it seems to have worked nicely. Thanks for the suggestions on that one! Now to my next round of questions:

In General questions | Asked By Michael Grundvig | Mar 12 18
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