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4 Answers

Reading list

the american philospher, john serle, once said, "if you can't say it clearly you don't understand it yourself.” i sometimes feel this way when i try to articulate the theory behind everyday building science. what books or periodical articles do you recommend to better understand phenomena like condensation and air movement; how insulation and vapour retarders work, et al...?

In General questions | Asked By erik olofsson | Mar 12 13
0 Answers

What siding over 2 inches foam and 1x4 furring? Fiber cement? LP Smartside? Cedar?

South Cental WI, 53951. Zone 6a. Currently have:
- OSB sheeting
- typar housewrap
- 1" polyiso foam, taped.
- vinyl windows installed on top of foam, flanges taped to foam

Our roof is neat standing seam in burnished slate (dark grey/brownish color). Brown facias, soffits and gutters.

In General questions | Asked By Nick Zees | Mar 13 13
1 Answer

DensArmor Plus

anyone know what tape to use for DensArmor Plus in a bathroom? the bathroom has a shower. i swear i read somewhere not to use regular fibatape but the only other non-paper tape i can find is alkali-resistant cement board tape. it looks like regular fibreglass tape but is grey jn colour...

In General questions | Asked By erik olofsson | Mar 12 13
4 Answers

Bathroom moisture control in HRV defrost mode

Planning new residential construction in moist and winter cold zone 5A.  Basement/walls/roof are R20/40/60, triple-pane, super-tight, well-drying, direct-vent, and mechanicals all in conditioned space.  I feel like I have covered most angles, and am looking for extra insurance against mold.
I'm planning for 2 mini-splits to handle 3000sf plus another mini-split for a 600sf in-law, and an HRV to not only provide exhaust/fresh air, but with the help of a few transfer grills, to also distribute heat & cooling throughout the fairly open layout.

In General questions | Asked By Bill Littlewood | Mar 11 13
3 Answers

Is anyone familiar with reflective insulation, specifically Think Smart?

I was introduced to it a a home show. The cost is about $2.75 per square foot. It seems high, but could get a 4-5 year payback. Comments please.

In Energy efficiency and durability | Asked By Tom Swanson | Mar 11 13
15 Answers

Mineral Wool Exterior Insulation, Humidity and Windwashing

Every time I think I have my insulation strategy set, I learn something new that makes me question it. That's what you get for reading the internet.

Anyway, I am planning on 2 x 6 walls with dense pack cellulose with a smart vapor membrane like Intello Plus, an insulated 2" service chase. Outside of the cellulose would be plywood, housewrap, then probably 2 inches of mineral wool exterior insulation (Roxul Comfortboard is my plan) then strapping, then Hardiboard. I am in zone 3 mixed-humid in the Piedmont of the Carolinas.

In Green building techniques | Asked By Lucy Foxworth | Mar 8 13
18 Answers

Greenest EVER insulation! (It's also very cheap!)

- 0 carbon/embodied energy
- easiest installation of all
- comes when most required
- very very DIY friendly
- can be moved around

u guessed it ?

water ....ergg SNOW of course :)

I join a picture view from my first floor patio door taken on feb 28 2013 for your enjoyment
( for those southerns that think we don't have snow in Canada ...wait everybody thinks we have tons of it ?? damn .. )

On a more serious note,
i've designed my flat roof terrace on my own house to take advantage of the snow we have each year during the coldest phase of our winter in Quebec.

In Green products and materials | Asked By Jin Kazama | Mar 7 13
6 Answers

Tape test results

The results of my test of eleven air sealing tapes on six materials has been published.

Anyone interested in reading the results can find them here: Backyard Tape Test.


In Energy efficiency and durability | Asked By Martin Holladay | Mar 8 13
18 Answers

What kind of chimney for an energy-efficient home?

The recent discussion on masonry heaters in super-insulated homes is great, and Martin's "farewell to the chimney" post is a classic, but I have a question that I don't think has yet been covered here.

I am designing a well-insulated home that will require a modest amount of Btu input that I want to provide with a modest woodstove. What is the best type of chimney to use, masonry or insulated stovepipe? (Or some other option I'm not specifying.)

In Mechanicals | Asked By Tristan Roberts | Jan 29 11
3 Answers

How to hit studs with 4.5 inches of interior polyiso?

I am starting to install my polyiso on the interior of my slanted cathedral roof assembly and am having trouble finding the studs through the 4.5" of polyiso that I have.

Things working against me:

1. not all studs are perfectly 16" OC.
2. The ceiling deck is at an angle.
3. When I place the screws in it's hard to get them into the studs or even find the studs with the angle of the ceiling.

Are there any videos or techniques that can help me find the studs...I'm at a loss here!


In General questions | Asked By Kevin Lauscher | Mar 11 13
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