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4 Answers

Sanity check on energy efficient window pricing

I'm pricing out energy efficient windows, and am wondering if the quotes that I'm receiving are typical. I'm looking at white, triple glazed, low-e, argon or krypton filled fiberglass new-construction casements with no grids. I've received quotes from two Canadian manufacturers that are both $47/ sq. ft, uninstalled. Does that seem in-line with other people's experience buying windows?

I'm aware that vinyl windows would be cheaper, and that double pane windows probably have better ROI. Having a firmer idea of pricing will help with that math for my house.


In Green products and materials | Asked By John Ranson | Sep 22 16
9 Answers

Condensation on plexiglass?


In fall-winter-spring, I have lots of condensation on my double-pane windows. After reading multiple sources on the Internet stating that condensation does not form on acrylic, I fastened a plexiglass sheet on a window to test. I lowered the double-cell cellular shades for the night.

This morning, I realized that the test failed - there was fogging on the bottom part (but no droplets). I guess I read the wrong sources or I did something wrong.

Which one is it?

Thanks for your help!

In General questions | Asked By Marc Delisle | Sep 25 16
3 Answers

Could a heat pump unit be used to heat a crawl space that is closed in?

I'm thinking about having a heat pump system added to my mobile home. The home is about 1500 sq. ft., with a crawl space about 3 1/2 ft from slab to bottom of the mobile home.
This would help heat the floor above and allow me from leaving my home unoccupied for a time during the winter and only have the heaters keep temps around 56.
Well above 35 degrees.

Could this be done?

In General questions | Asked By Leonard Klinger | Sep 25 16
3 Answers

Uninsulated flex duct: Does it lose its sound-dampening qualities?

I'm working on my HVAC material list. All of my branch lines are short and straight. I see where people suggest flex duct for these applications (if installed correctly) for it's sound dampening benefits. However, I am running the ducts inside soffits, and I want the ducts as small as possible so the soffits don't get too big. Since I am inside the thremal envelope, I don't need insulation. Insulated flex duct adds 2-4" to the overall duct size.

In Green products and materials | Asked By Clay Whitenack | Sep 24 16
58 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

In Energy efficiency and durability | Asked By Susan Hanway | Aug 28 16
1 Answer

Rain screen detail on chimney box with brick veneer and flashing detail

Building chimney box on peak of roof for chimney pipe and plumbing vent to exit. Thin brick veneer with a rain screen detail. The lid for the chimney box is elevated 1/2" for an air gap with 3.5" down turned legs for weather protection. All good so far, but when I go to install the step flashing on the roof next to the brick and then the cap flashing over that which it's mortared into the grout line, there is now no more ventilation from the bottom of the rain screen as it has been sealed off with the flashing details.

Is this an issue?

In General questions | Asked By eric Mikkelsen | Sep 24 16
3 Answers

Is HPWH reliability still an issue?

I'm seeing a lot of negative feedback on the reliability of heat-pump water heaters. Are they much more prone to problems than straight resistance heaters? If you had to choose a 50-gallon domestic model, what would you choose?

In Mechanicals | Asked By Charles Campbell | Sep 23 16
4 Answers

How far should poly run up the edge of a monolithic slab on grade?

How far should polyurethane run up the edge of a monolithic slab on grade? If it doesn't run all the way up (as I've seen in some details), should the edge be painted with damp-proofing?


In General questions | Asked By John Ranson | Aug 21 16
12 Answers

Following up on the musty smell in our crawl space

Editor's note: This is a follow-up to a previous thread on GBA. The previous thread was Why do I have a musty mildew type smell in my conditioned crawl space?

In General questions | Asked By Linda Larochelle | Aug 26 16
12 Answers

ZIP system R-sheathing on a Roof

I'm looking for a poor-man's alternative to thick polyiso on a roof and was wondering why ZIP system R-sheathing is not "allowed" to be on a roof? From Huber's web site:

"Zip System R‐Sheathing is currently limited to wood‐framed wall applications only. DO NOT use roofs or light gauge metal framing. For systems requiring multiple layers of water‐resistive barriers, ZIP System R‐Sheathing is intended to replace only the first."

My roof is extremely unique and you will all probably roll your eyes, but here we go:

1. My Roof is vented with baffles

In General questions | Asked By Christiaan Lutzer | Sep 20 16
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