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6 Answers

What to do with SIP face exposed below siding?

We are building our first SIP house complete with SIP foundation. We will be using Hardiplank siding which requires 6" clearance between the lowest plank and grade.

So for those 6" or so the skin of the panels will be exposed, and in certain areas it may not be the foundation panels which will have the pressure treated plywood, etc.

So this general question is: What should I do with that space? Normally this space is just exposed poured concrete walls, but with a SIP building, what do you do?

In Green building techniques | Asked By Joe Hartwig | May 7 13
3 Answers

Optimizing use of rigid foam for top plate/soffit?

I want to blow cellulose in my attic, but it is impossible to get a very good r-value in the tight space where the roof slopes down to the soffit.

In Energy efficiency and durability | Asked By Nick Welch | May 9 13
11 Answers

Should I put poly behind tongue-and-groove paneling on exterior walls?

Location is in NE Ohio. 2x4 wall construction, fiberglass insulation, OSB and 3/4" polyiso exterior foam and finally housewrap. Some AC for one to two months a year.

In General questions | Asked By Richard Hummel | May 2 13
5 Answers

With a multi-zone mini-split, does the indoor unit or the outdoor unit decide when to turn on?

Background: new home to be built in Zone 4A. Living area about 2200 sq.ft. on main level. On lower level is a 778 sq.ft. shop space, and 450 sq.ft. for future use. My energy rater estimates the cooling load at 18,000 BTUs for everything.

I’m thinking mini-splits. Mitsubishi offers several outdoor heat pump units that can have 2, 3, or even 4 zones, matched with any mix of the interior units (with an appropriate combined total of course). I’d like at least three zones to meet both distribution and the diverse needs of the spaces, but there’s a big question.

In Mechanicals | Asked By David McNeely | May 7 13
6 Answers

Should I insulate around the edges of a basement slab if it has in-floor radiant?

I'm building a house in zone 6a. Local codes require 2" of rigid foam on the outside of the foundation wall, so that's what we did. We plan to insulate under the basement slab (1.5 or 2 inches of rigid). We also plan to install radiant heat in the basement slab. Should I insulate around the edges of the basement slab to prevent continuous thermal bridging and heat loss from the heated slab into the foundation wall and eventually down to the footing and into the ground?

In Energy efficiency and durability | Asked By Mike McKernan | May 8 13
5 Answers

Managing overheating in a 1.5-story home

I’ve purchased a small 1950’s 1.5 story (or Cape style) house, where the second floor has knee walls and sloped ceilings. We’re in Nova Scotia, Canada which is a cold climate but spring/summers can get hot. We plan to super insulate the house using the PERSIST/REMOTE approach when we can afford to, but in the meantime the house has no mechanical ventilation and minimal insulation. The second floor bedrooms are already getting uncomfortably warm on sunny days. I’m curious what methods can be used to manage the overheating in this type of building.

In General questions | Asked By Mark Fredericks | May 8 13
3 Answers

Problems with configuring minisplit system as ONLY heat source

I am having trouble finding the best possible configuration for a mini-split system. I'm building a small house in NW Ohio, a story-and-a-half with full basement). Total calculated heat load is 16,000 Btu/hr.

In Mechanicals | Asked By Andy Chappell-Dick | May 9 13
3 Answers

Shock absorbing system for exterior dance floor?

I'm building an exterior wood framed, 8 by 8, 1/2" marine grade plywood dance floor, (1 layer only) so a typical floating floor method won't work. Is there a way to put , maybe, bridge rubber or springs, or some polycarbonite foam in between the pier block and the bottom of the floor joists, or in between the top of the joist and the plywood for some flex in the floor for the dancers legs?

In General questions | Asked By Roger Aiton | May 7 13
51 Answers

Open-cell foam on roof deck

My house is spray foamed with open-cell Icynene on the roof deck as well as all walls. I have an HRVv for fresh air.

Everything's been good but I'm noticing now that the humidity in the attic starts out around 36% in the a.m. but gets up to 60-70% during the day then back down to 40-50% at night. The temp is always within 5% of the house temp. I'm not sure what to do.

There isn't any moisture sources in the attic. To make it more confusing is, there are two separate attics and both are doing the same thing.

Any help would be greatly appreciated. I don't know what to do.

In General questions | Asked By mark hanson | May 1 13
1 Answer

What to do about undersized Marvin double-hung windows installed without spray foam, with sloppy exterior caulking?

After reading all of the FH and GBA articles I could, I elected to order Marvin Ultimate custom-sized insert double-hung windows for my 1910 brick row house with a flat roof since I had limited options to improve the energy efficiency and comfort without disturbing the plaster or reroofing. My storms didn't help much and I vowed not to put up plastic another year.

In General questions | Asked By sharon slovenec | May 7 13
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