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4 Answers

What is the minimum permeability for drying to the exterior in Zone 6?

Are there guidelines on the minimum permeability you should have in an exterior wall assembly for drying to the outside? For a cold climate, specifically Zone 6 in Halifax. We get a fair amount of rain and I'd imagine it'll depend on that as well?

In Energy efficiency and durability | Asked By Wesley Manning | Jun 21 15
3 Answers

ERV / HRV Details

The more I read both here in discussion forums and in articles, the more I ponder various concepts, and the more perplexed I end up. I'm a homeowner undertaking a gut-renovation on nights/weekends/holidays. I'm trying my best to balance idealism and the realistic necessities of my budget.

~2000 sf house in Southern CT; CCSPF insulation throughout; Hydro-Air HVAC system. I'm pretty well convinced that an ERV is the correct choice.

In Mechanicals | Asked By Matthew Kreuzkamp | Jun 22 15
4 Answers

Is this a good plan for updating our wall layers?

This site has been a HUGE help with putting together our plan for updating our 1986 built home while replacing the roof and siding due to a hail damage claim. We live in Columbus, Ohio (zone 5). We have a gas furnace. Thank you!

Our recently updated plan is described below. We plan to have the install done within the next week or two.

1. Should I be concerned about having multiple vapor barriers on the interior with the addition of foam on the exterior? I've read your articles which express concerns about that because of the need to dry to the interior.

In Energy efficiency and durability | Asked By Chad B | Jun 22 15
1 Answer

Air conditioning fans

Hello Mr. Holladay,

My house is located in central Florida. It is a two story house and has additional vents in the hallway and each bedroom. All but one shoots out cold and the other shoots out hot (right in the circulation path to the thermostat).They are and are facing the walls. I was told to by a friend to cover the one that shoots hot air so it doesn't keep the thermostat running.

Is this safe to cover it up or is the hot vent meant to do this?

Why were they installed, facing the walls, and why is one shooting out hot air?

Thank you for your time with my concern.

In General questions | Asked By Tim Spaulding | Jun 22 15
3 Answers

Linoleum over slab with a layer of insulation - Kerdi-board

My daughter's school (Vermont) has the pre-school on the walk out basement level. The floor is old vinyl tile directly on an uninsulated slab. The floor is cold in the winter and condensation is an issue in the warmer months. Donated carpets are changed out periodically and we did a whole building Air exchange system which improved air quality quite a bit. Headroom is an issue on this floor.

In Green products and materials | Asked By Robert Swinburne | Jun 22 15
8 Answers

Moisture management for tiny house subfloor?

My husband and I are just about to start building a tiny house on a trailer in Nashville, TN, and I'd like to make sure our subfloor does a good job of protecting against moisture, as well as drying out when necessary. Any advice would be greatly appreciated!

Our current setup, from bottom to top, is:

- Steel trailer frame
- Metal flashing
- 2x4 framing filled with Roxul, anchored to steel flanges on the trailer using bolts
- 3/4" Advantec with taped seams, which will connect to ZIP system sheathing as our air barrier
- Cork floating floor

In General questions | Asked By Michaela Riley | Jun 20 15
3 Answers

Minisplit choices

I am looking to replace window ACs with split units but am running up against a common problem - multiple small rooms that each need their own cooling, but using individual heads will result in excessive cooling capacity and the problems it brings with it.. 3 small (2x 10x12, 1x 10x20) bedrooms, living room , and EI K all need cooling. Metro NYC area.

In Mechanicals | Asked By Richard Jackman | Jun 22 15
2 Answers

Best practices regarding blown-in insulation in a double-stud wall?

Martin mentioned in another Q&A that choosing a contractor with experience installing blown-in insulation in a double-stud wall is important because of multiple ways it can go wrong. I am going to build my first dble-stud wall home soon and would like to know what to look for/ask for regarding a proper install. In our area (climate zone 4C) dble-stud walls are not common. I can imagine that getting the proper density might be challenging without discrete stud cavities to pack. Advice?

In General questions | Asked By David Landry | Jun 20 15
9 Answers

Drainage and prep requirements for a basement egress door

Hello, all,

I'm poking around trying to do my due diligence and see how feasible it is for me to install a basement egress door in the spot where I've got an existing basement glass block window. Before different contractors come and tell me I do-or-don't need this-or-that, I'd like to get a sense for what's appropriate.

In General questions | Asked By Minneapolis Disaster | Jun 19 15
10 Answers

Feedback on this sill insulation overlay detail

So I'm considering changing using this detail instead where the insulation covers the sill and comes down to the top of granite veneer, while inside the foundation the interior insulation comes up between the joists. It sounds like a typical basement detail - but it's fairly unique because of the granite veneer and the way I insulated in front of the joists, by using a shelf on the inside....it's decision time reaaaaal soon - so thoughts - criticisms - whatever!

In General questions | Asked By Brad Hardie | Jun 21 15
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