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3 Answers

Polyiso on the inside?

A question from a DIY prospective.... I can see a point of adding rigid foam insulation on the outside. But for a 2-story house, and a do-it-yourselfer, it is a bit of a scary project - you have to complete a lot of work in a short time, and get a lot of details just right.

In Green building techniques | Asked By Vladyslav Ovchynnikov | Aug 15 13
5 Answers

Roofing underlayment for vented cathedral ceiling

After finally deciding on my insulation thanks to this previous thread: Insulation Delirium (thanks again everyone). I am now talking with my roofing contractor and I have a follow up question, though it seems a new thread is most appropriate.

In General questions | Asked By Andrew David | Aug 13 13
4 Answers

Approach for adding insulation to existing concrete walls?

We just purchased a new (built in 1951) home and are working on some renovations before we move in. One major issue is the lack insulation in the entire house. The exterior walls are built of concrete block with full brick on the outside. Then looks like the interior plaster was put right up against the concrete block. The house used to have a flat tar roof, the previous owners added engineered trusses to create an attic space. Only insulation we have found is between the interior ceiling and old tar roof, nothing in the walls or the new attic.

In Energy efficiency and durability | Asked By Kathleen Kendall | Aug 10 13
1 Answer

Water-blown closed cell SPF

Is water-blown (or non-HFC blown) closed cell spray polyurethane foam (SPF) available?

In Energy efficiency and durability | Asked By Robert Pinto | Aug 15 13
1 Answer

Is it safe to paint Polyisocyanurate Insulation?

I have a lot of Polyisocyanurate Insulation in my basement. We are not at a point where we can finish our basement, but I'd like to at least get it looking a little nicer so it can be used as a playroom - carpet on the floor, paint on the walls.

The top half of the walls is this Polyisocyanurate Insulation. It has a reflective aluminum facing.

Is it safe to paint this? Will it decrease the effectiveness of the insulation?

Thank you!

In Green products and materials | Asked By Brittaney King | Aug 15 13
1 Answer

Concrete slabs: fiber or mesh for best practice?

My engineer calls for 6x6 mesh placed at mid-slab on supports, and has drawn control joint locations.

Joe Lstiburek recommends fiber-reinforced concrete with a water-to-cement ratio of less than 0.5, and control joints, because he says no one ever puts mesh on chairs anyway.

Can GBA Pros provide best practice guidance? If fiber, is there a standard I can use in my notes?

Also, does the advice apply to exterior hardscape?

Building Zone 4A. Thanks!

In GBA Pro help | Asked By David McNeely | Aug 15 13
0 Answers

What are the best hurricane-proof skylights for a residence in South Florida?

The real problem is the roof contractor's high labor rate to install 4 standard-size skylights. The current skylights need to be replaced to receive a $700.00 discount from the insurance company.

Suggestions and recommendations please.

Philip Lord Flint
511 Misty Oaks Drive
Pompano Beach, FL. 33069

In Building Code Questions | Asked By Philip Lord Flint | Aug 15 13
7 Answers

If a home is too tight and does not have provided mechanical ventilation, can it draw in humidity and excessive heat during peak times?

I have a customer that purchased a home eight months ago and all summer long he has complained to the builder that the temperature and humidity levels are way too high. I performed a blower door test and found that the home is 2000 cfm lower on infiltration than what BPI recommends.

In Mechanicals | Asked By matt tucker | Aug 13 13
0 Answers

I'm looking for a green architect/designer/contractor in the San Francisco/East Bay area

I am doing a single family home reno in Lafayette, CA and want professionals who are up on building science ... roofing, infiltration, insulation, etc. You may recommend yourself if you think you qualify. You may email me direct at ballerina4hire-cashonly@yahoo.com, if you prefer. No spam please.

In General questions | Asked By Joe Karen | Aug 13 13
4 Answers

What type of water heater and where?

I was planning to install an electric heat pump water heater in my new house. I really liked what I read about the Airgenerate ati66. But apparently so do a lot of other people. The ati66 is in short supply and not distributed in my region. I can possibly buy one and have it shipped from the West coast.

I could possible substitute an AO Smith Voltrex 80 gallon. It would be easier to source and support than the Airgenerate.

In Mechanicals | Asked By Steven Knapp | Aug 12 13
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