Q&A: A Forum for Green Building Experts and Beginners

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!


3 Answers

Insulating underneath wood shingles underneath asphalt shingles

Hello!

I've done my research and read quite a few relevant posts and articles here, but I couldn't find an exact match for my situation.

Legend has it that my home was built in 1876 in Philadelphia and moved here to Harrisburg via barge sometime after that. I'm in Climate Zone 5.

My wife and I are looking to build an insulated cathedral ceiling. Yes, I've read the wonderful GBA article :)

Asked By Drew Buglione | Sep 20 16
2 Answers

Polyiso in bonus room

I'm starting the process of finishing my upstairs I'm located in piedmont of north Carolina. My house is 5 years old I have soffit and Ridge vents 1 dormer simple roof line 2x6 rafters . I found a deal on Craigslist for polyiso the problem is its foIL faced on both sides . My plan was to cut and cobble 3.5" pieces between rafters flush to interior of rafters leaving a 2 inch gap from soffit to Ridge vent then install 3 " polyiso on inside of rafters to adress thermal bridging then 1x3 nailers for sheet rock. Is this a sound plan?

Asked By Eric Teer | Sep 24 16
55 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

Asked By Susan Hanway | Aug 28 16
55 Answers

Mooney floor

I want to put insulation on top of a concrete floor.
A layer of foam + plywood bolted to the concrete has been suggested. (By Dana I think)
While that looks an good option I've been exploring more low cost options.

What about a Mooney wall, flooring variation.
Thinking about 2x4 + 2x4, filled with blown in cellulose. Likely GreenFiber or InsulMax.

Is that a good alternative?

Asked By Tony Tibbar | Aug 6 16
35 Answers

Have many questions about HVAC, insulation, and ventilation

I have many questions about HVAC, insulation and ventilation, but will just start with a few. If we decide on an exhaust-only system for a new build home, does also trying to button up the envelope tight work with that type of ventilation?

We will probably insulate with fiberglass blown in at attic floor because spray foaming the whole attic would be so much more expensive. If we don't insulate at roof, do we need to install a radiant barrier at some location to try to bring the heat down in attic?

Thanks.

Asked By C Clark | Sep 21 16
2 Answers

low E

I just installed some high end french doors that came with a sticker warning 'DO NOT SCRAPE GLASS". Does anyone know anything about this? Is it some new kind of low E film, have there been long term problems with scraping low E glass?

Asked By william Goodwin | Sep 24 16
2 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?

Asked By Charles Campbell | Sep 23 16
0 Answers

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?

Asked By eric Mikkelsen | Sep 24 16
7 Answers

Air sealing

I am in the process of building a new home in zone 5. We are doing a passive solar house with vaulted ceiling in the living room, kitchen and dining room area and the rest of the house will be flat ceilings. I plan to do blown in cellulose insulation on the flat ceilings and closed cell on the vaulted ceiling. I plan to do 3” of rigid foam insulation on the exterior walls with spary in cellulose (2x6) walls. I am also using Prosoco seam filler for the sheathing and Fast Flash for the flashing.

Asked By Michael Brackett | Sep 23 16
0 Answers

Un-insulated flex duct...loses it's 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.

Asked By Clay Whitenack | Sep 24 16
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!