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4 Answers

Retrofitting an uninsulated slab for radiant

We are planning a major renovation of our 1970s ranch and would like in-floor radiant heat. The house is on an uninsulated slab in climate zone 5A. Our current plan is to insulate with 1.5" XPS over the slab, lay Schluter Bekotec over the insulation, place the the PEX in the Bekotec, screed then tile thoughout the house.

In Plans Review | Asked By Jessica Marchesi | Apr 6 14
1 Answer

Martin Holladay will be speaking this week in Montreal

Martin will be speaking on "Affordable Green Homes for Cold Climates" in Montreal, Quebec, at 7:00 p.m. on Friday April 25, 2014. The event will be held in Room 3110 at the School of Architecture at the University of Montreal. He will be speaking in French.

For more information on the event, visit the Maison Saine website.

In General questions | Asked By Martin Holladay | Apr 21 14
12 Answers

REMOTE vs. PERSIST approach for a flat roof?

I'm not sure I fully understand, but the REMOTE system states an advantage over PERSIST by allowing more insulation in the roof and not building a second roof structure.

Does this advantage apply for a flat roof?

I'm also trying to understand whether a vapour permeable barrier is needed for the roof and walls on the outside of the sheathing, before the exterior insulation is installed. REMOTE promotes vapour permeable, and PERSIST uses impermeable.

In Green building techniques | Asked By Jerry Chwang | Feb 11 14
2 Answers

Roof insulation

I am rehabbing a house located in zone 5, Pennsylvania. The room I am working is a kitchen with a cathedral ceiling. The room is completely gutted. The rafters are 2 x 10 on 24 o.c. The roof pitch is about 15 degrees.

In General questions | Asked By Anthony Jackson | Apr 21 14
2 Answers

We need some advice on a solar envelope house

My husband and I are considering a home on a huge lot we love, but we found out it is a solar envelope home built in 1983. I've read mixed reviews on this type of home and we have some concerns. We'd appreciate any help!

1. If we wanted to ever convert it to a normal home, is that possible?

2. Have people really experienced health issues stemming from mold and modes growing in the walls and under the house from the moisture in the air? How common is that? Fires seem to be a concern too.

3. This home is in southwestern Illinois. Will it really make a big difference in our bills?

In Energy efficiency and durability | Asked By Erin Litteken | Mar 22 14
2 Answers

What is the best angle for a skylight on a low-slope roof in Chicago?

I am replacing a 30 year old plastic bubble skylight as part of a major remodel. The skylight is located a flat (low slope) roof in a typical Chicago small residential building and serves a third floor bathroom. The skylight will not be openable.

I have searched this site, the web, and the manufacturer's installation information, but am still unsure how to orient the skylight to maximize its benefits, while reducing drawbacks, like unwanted heat in Summer. It appears that the only requirement is that the skylight be installed at a slope greater than 15 degrees.

In Energy efficiency and durability | Asked By Dan Nehm | Apr 19 14
1 Answer

Where should vapour barrier be in double basement wall?

Walkout basement in zone 4C (west coast) 2x6 framed exterior wall with r20 fiberglass batt insulation. To eliminate the 'step' (many houses have a finished shelf) of concrete foundation which comes up 2', client wants walls framed from floor to underside joist inside foundation to avoid the shelf, creating a space between the framed exterior wall and the new interior wall. Should the vapour barrier (6 mil plastic be relocated to inside of newly framed wall, and if so, should new wall be insulated? the full cavity be insulated? thanks, dan

In General questions | Asked By dan nugent | Apr 21 14
7 Answers

Heating for small bathroom?

I am renovating my house, installing solar panels and getting rid of my gas forced hot air system and replacing with mini-splits (very small home < 1000 sq feet)
I would like to install an energy efficient heating system in the bathroom (about 6' x 8') as I'm not sure the heat will effectively get there, plus I like to have a separate zone for the bath for the usual reasons. i had thought about electric radiant heat in the floor but have heard that can be quite an energy drain.
Do people have a suggestion for a very small heating unit for this purpose?
Thanks!
Maggie

In Energy efficiency and durability | Asked By maggie wilbur | Apr 19 14
2 Answers

Passive house and sunshine hours

is there a ballpark rule of thumb that spans different regions for the mean monthly sunshine or possible percent sunshine that is conducive to a favourable result in PHPP?

In PassivHaus | Asked By erik olofsson | Apr 20 14
4 Answers

Rigid foam insulation over Bildrite during remodel/reside?

I have a recurring question / situation that comes up in my east central MN location (6b-7a border). There are many 1970's homes undergoing remodeling and looking to add insulation for improved comfort and energy effciency. Miost common construction is drywall, kraft faced R13, 2x4 walls, 3/4" Bildrite (asphalt fiberboard sheathing).

In Energy efficiency and durability | Asked By Troy Tvedt | Apr 17 14
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