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9 Answers

Slab on top of slab: Building science?

I have an existing foundation which is a trench poured monolithic pour, slab on grade with the perimeter foundation walls extending 40 inches to the frost line. It has perimeter stem walls extending 24 inches above the floor slab. The room is unheated, 400 square feet, used 9 months of the year. It has 9 foot walls and vaulted ceilings.

Architectural plans for the room call for the floor to be elevated 14 inches from the existing. The monolithic pour is uninsulated and has no poly in place under it.

In General questions | Asked By Dennis Dipswitch | Apr 29 14
13 Answers

I am thinking of using Huber’s new Zip System R-Sheathing on new construction

I have three questions:
1. What has been users' experiences with this product?
2. Do I need to install a rainscreen over it if I am installing fiber-cement siding?
3. What’s the best insulation in the 2X6 wall behind it? Is flash & batt overkill?

In Green building techniques | Asked By James Kuszaj | Apr 26 14
155 Answers

Serious Windows vs. Thermotech, Fibertec, Inline, Accurate Dorwin

Does anyone have experience with Serious Windows or Canadian fiberglass windows? I'm having a difficult time finding high SHGC windows (with a U-value less than or equal to 0.30) for my passive solar home that are affordable. Looks like the fiberglass windows can give me the performance I'm looking for, but I can't find any local installations to inspect the quality of manufacture.

In Energy efficiency and durability | Asked By Claire Anderson | Oct 1 09
5 Answers

Tightening up a 1949 mid-century modern

I just bought a really cool 1949 mid-century modern 2200 s.f. split-level home in the Chicago area (Zone 5) and will be doing a bit of work to it. The work to the exterior consists of all new siding - cement fiberboard and cedar siding set over the existing sheathing as a rain screen on 1x4 furring strips. I will be adding 1 1/4” extruded poly where the cement fiberboard is going, and for aesthetic reasons, adding 2” extruded poly where the cedar siding is going. I will cover the sheathing with the a WRB. New orientation specific Integrity Low E windows will be set as ‘outies’.

In Green building techniques | Asked By Nathan Kipnis | May 1 14
2 Answers

Paint that rejects heat?

I am from Mexico, just crossing the border of Brownsville, TX. Like 15 years ago I brought a house in Matamoros, Tamaulipas, Mexico. This is a production house made by Infonavit, a government agency made for low-income families. After suffering for around 5 years of severe hot weather and with little money to invest on my home, somebody told me about a paint that rejects the heat and only cost about 60 dollars.

In Energy efficiency and durability | Asked By Manuel Hernandez | Apr 30 14
8 Answers

Heating/Cooling Loads - Oversized and not correct?

Hi everyone!
I am finally getting ready to dig and got back my system sizing and I have a few questions as it seems over sized and what homes normally receive without this amount of insulation and product.
What first led me to believe something looked off was that my heating load was higher than my cooling as well as the sqft area of the rooms were not looking correct.

If you wouldn't mind taking a quick look and helping me understand if it seems correct or that I should have a conversation with the individual that I paid to size my system and perform the duct work design.

In Mechanicals | Asked By Matt Anderson | Apr 30 14
4 Answers

Help — Critters in my windows

I don't know if this is a question you have ever seen before. Recently we decided to remove a window and close the wall up. It was not possible to remove the window intact without damaging the siding, so my husband cut the frame and removed it in pieces. The windows are typical vinyl single-hung windows. They seem like good energy-efficient, double pane windows and are newer.

In GBA Pro help | Asked By L H | Apr 30 14
8 Answers

New construction: Where to spend the money?

My wife and I may be building a home soon. We are on a tight budget, so I'm wondering what's going to give us the biggest bang for the buck.

A few facts:

- We are in zone 4A

- Crawl space foundation

- The house will either be a roughly 2,600 sq. ft. one-story (plus bonus room over garage), or a roughly 3,000 sq. ft. two-story. These are the minimum square footage requirements set by the HOA.

So, any advice on where we should spend more money to increase efficiency would be appreciated. An enclosed crawl space is pretty high on my list right now.

In General questions | Asked By Michael Geoghegan | Apr 29 14
4 Answers

Thermo-Ply under drywall?

I am working on a ranch style house. We have pulled all plaster and insulation from the ceilings in the house. As we start to put the ceilings back together, can I use a product like Thermo-Ply on the underside of my ceiling joist and drywall over that? That gives me the advantage of being able to put the ceilings partly back together, re-insulate the attic with blown insulation, and then drywall at my leisure.

I am putting blown-in to R-36, and will have an air space above to vents. No storage in the attic, and no mechanical.


In Energy efficiency and durability | Asked By Ralph Vickers | Apr 29 14
8 Answers

Roxul batts and Roxul Comfortboard insulation without plywood?

I'm building a timber frame house in Vermont and was thinking of using Roxul batts in the 2x4 stud walls (studded between the posts). Then putting 2" of Comfortboard on the exterior, then strapping vertical and horizontal for cedar shingles.

One question I have is that since I've made the timber frame so rugged and stiff, (I have hardwood 3x5 bracing going from close to the post tops down to the sill, it is not moving), I decided not to have plywood or rough-cut boarding on the frame. Is there any problems with this with air or vapor passing through?


In General questions | Asked By Seth Kelley | Apr 28 14
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