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12 Answers

Insulating a P.W.F. (Permanent Wood Foundation)

I purchased a house with a PWF a few years ago in southern Michigan. I am interested in finishing the basement now, and would like some advice on insulation options for the walls. The pwf is constructed of 2x6's on 12" centers with 3/4" exterior plywood. From what I can see the outside is wrapped with a some type of poly / plastic wrap, and I don't believe there is any exterior foam type insulation. I would say most of the walls are completely below grade, but certainly some portions that are not - if that impacts the insulating plan.

In General questions | Asked By Chris | Jan 2 16
2 Answers

Recommendation for wood double-pane windows?

We recently noticed moisture intrusion under a window in our house. I had a mold inspection company do further testing, and eventually we determined that the window was leaking and there is mold inside of the wall there. The house was build in the 1920s and the windows are old single-hung wood.

In Interior design | Asked By Chris Durand | Jan 4 16
3 Answers

I have a very tight 1800 sq ft home that is need of an air circulation system.

Is it possible to use a ductless air conditioning system to bring in fresh air?

In Energy efficiency and durability | Asked By brian Adessa | Jan 4 16
4 Answers

Can I cool an old house with 1 minisplit... in the attic?

my 1953, 1300 sqf, new to me florida ranch 3bed/2bath has an HVAC issue. The current system is a heat pump split system with ducts, located in a *completely* non-insulated attic. I mean, NO insulation. Not on the floor/ room ceilings. Not under the roof. Nowhere. The attic is super small, which means that not only there is no way to add insulation without removing the ductwork and the air handler (and not putting it back), but also that the ductwork is very poorly done (squeezed everywhere, not straight, sharp bents, etc.) making it a very, very unefficient HVAC.

My plan is to:

In Energy efficiency and durability | Asked By damien kirrmann | Jan 4 16
1 Answer

Zone 2 Vented attic

We live in Houston and have an attic with soffit and ridge vents.
This is bringing in hot humid air. (100+ degrees 90%+ humidity)
The air handler and ductwork is in the attic.
I'm considering converting the attic to an unvented space, but am confused about vapor permeability for the high outside humidity associated with Houston. Everything I've read about making an unvented attic seems to apply to colder/dryer climates.
Should we use closed cell foam under the rafters or do we need to use rigid foam above the roof sheathing?

In General questions | Asked By Michael Trout | Jan 4 16
4 Answers

Yet another heat pump question

Hello, all. Hoping for some guidance. Looking to install heat pumps to supplement (or replace?) existing oil furnace in an 1880’s house with lots of walls, small rooms, and very little open floor plan (see attached images, please).

I’ve had two contractor present very different options.

Contractor # 1

First floor: Two (2) Fujitsu m/n ASU9RLF1 9K BTU ductless wall units. One at kitchen and one in livingroom to serve entire first floor.

Second floor: One (1) Fujitsu m/n ARU18RLF 18K BTU ducted unit with four ducts to serve 3 bedrooms and bathroom.

Contractor # 2

In Mechanicals | Asked By Christian | Jan 1 16
2 Answers

Passive solar home design

My wife and I will be relocating to a small town outside of Clemmons, NC. we have land that is directionally well set for a passive solar home. I have been searching for someone in the area that I can hire as a consultant and help design a passive solar home that is reasonable in price both in design and building costs (seems like most of what I have been finding on searches are extremely expensive and/or generic plans). Is there someone in the Winston-Salem area that I would be able to talk with?

In General questions | Asked By Al | Jan 3 16
15 Answers

How do I get hot water to shower faster?

Just installed an LP tankless hot water heater. It is about 40 feet to the shower. I have 3/4" pipe, on a well that delivers about 40PSI. Thinking about going to 1/2" pipe for hot water supply to reduce volume that has to be heated up. I have insulated all the runs.

thanks for help.


In Energy efficiency and durability | Asked By Bruce Stubaus | Dec 28 15
7 Answers

Planning for a roof insulation retrofit - SPF vs. Polyiso?

We are doing a gut renovation of a home that includes super insulating the walls (1.5" polyiso wrap + 2x4 stud bays furred out to 6"). The roof is in good condition, so we are leaving it for now.

Plan is to eventually put 4" polyiso (R23) on the roof when the shingles wear out, and use metal roofing. This is what I have seen a lot of on this site. Have not got a quote on this, but I imagine well over 10k, given the new roofing, adding bigger overhangs, etc.

In Energy efficiency and durability | Asked By Reanna Alder | Jan 1 16
2 Answers

Looking for Energy Star contractor in Hudson Valley, NY

I'd like to get a home energy audit and do some sealing/insulating through the NYSERDA/Energy Star program. The NYSERDA web-site lists a couple dozen Energy Star, BPI-certified "Home Performance" contractors in my area (near Poughkeepsie, NY), and I have no idea how to chose. Does anyone in the area have experience doing an audit/retrofit with a local contractor? Alternatively, if there is a contractor who is reading this web-site, that would be enough to recommend you!

In General questions | Asked By Jeff Seidman | Aug 29 13
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