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!


5 Answers

Best brand of screws with washers for steel roofing?

The painted steel roofing panels on my simple 4:12 gable roof will be attached to 2x4 strapping with exposed fasteners. The #9 x 1-1/2" screws with EPDM washers used to secure the roofing to the wood range from around 12 cents each made by Metal Sales, who make lots of steel roofing such as ClassicRib, to a not-yet-specified brand that are 8 cents each. The Metal Sales screws are described as having "Metal encapsulated in EPDM for extra strength." How significant are the differences between the brands of these screws, and which do you recommend?

In Green products and materials | Asked By Jeff Cooper | Feb 9 16
13 Answers

Whirlpool HybridCare discontinued?

I was just looking on the Whirlpool website for some information on the HybridCare ventless heat pump dryer, and it is listed as discontinued!

I contacted them to confirm and find out if a new model will be coming out or if they are abandoning their heat pump technology, but have not heard back.

Anybody else hear anything on this?

Thanks.

In Green products and materials | Asked By Stephen Youngquist | Jan 27 16
2 Answers

Do they sell Dow Thermax anymore?

I have a big basement I need to insulate from the interior and I'd like to avoid the cost of framing and drywall since the basement will only be used for storage.

Do they still make Dow Thermax? I can't seem to find it anywhere. Is there a new product that meets the fire ratings as Thermax, that won't require drywall over it?

In Green products and materials | Asked By Clay Whitenack | Feb 9 16
7 Answers

Spray foam directly on underside of roof?

I have a conditioned attic, currently insulated with R19 fiberbatts between the rafters. No airsealing, hence I want to remove the fiberbatts and spray 3 inches of closed cell spray foam in before putting the fiberbatts back in place. The attic is unvented, for instance no ridge vent exists. Should I put any membrane or the like on the underside of the roof sheathing before spraying the foam in ? I was thinking that would help with keeping the insulation intact in case the roof needed repair later on?

In General questions | Asked By matthias paustian | Feb 9 16
8 Answers

Leaky Ductwork in Basement

After getting a very poorly rated energy audit from our electric company, I'm working diligently to get our house more air tight. Seeing lots of posts about HVAC equipment, I'm thinking ours is a little lacking. It is 5 years old, the furnace is 95% efficient. But, the black tape is falling off and according to infrared, it is leaking. I've attached several pictures and also infrared pictures. We are in zone 5 (NW MO). It is 20 degrees outside and our basement walls are 47 and 53 at the frost line.

In GBA Pro help | Asked By Becky Parrish | Feb 9 16
3 Answers

Appropriate treatment of shower/tub walls adjacent to dense-packed cellulose?

Climate zone 4C marine, planning for new construction.

Planned typical R-26 exterior wall section: fiber cement siding, 1X rainscreen furring, 3" 8pcf rock wool, taped sheathing (primary air control and WRB), 2X4 load-bearing wall with 3.5pcf cellulose, 1/2" gypsum board.

How should interior high-humidity areas like showers adjacent to this exterior wall section be handled?

In General questions | Asked By Stuart Friedberg | Feb 9 16
33 Answers

Best insulation for indoor air quality?

I cannot decide on a type of insulation for our new home. I want something that is the safest for indoor air quality. I am worried about the off gassing of spray foam, but am also worried about the borate used in blown in cellulose (mainly the reproductive effects of borate). Please help! I want energy efficiency, but indoor air quality is of primary concern. Thank you!

In Green products and materials | Asked By Carolyn Farrow | Feb 8 16
2 Answers

A couple of renovation questions regarding my 1960 Cape

Hello all, I was looking up information on housewrap, and stumbled upon this website, what a great find. Anyways, I’m hoping to get some information/advice as the best way to go about doing some renovations this spring/summer on my house

In General questions | Asked By Khouri Rice | Feb 9 16
2 Answers

How do I calculate the interior temperature of a window at a given outside temperature with a fixed interior temperature?

I am trying to predict at what outside temperature will I get condensation on my windows. If it is 70 degrees inside with 40% relative humidity and my window has a u-value of .3 at what outside temperature will the window (frame and center of glass) have condensation. How do I calculate this?

In GBA Pro help | Asked By Chaz Steffen | Feb 9 16
4 Answers

Homemade dog house insulated panels

I'm having to make a homemade dog house for my rather large Akbash mountain dog family (papa, mama and 12 wk old pup). I live in Region 5, western Colorado. I need a floor panel, roof panel, and 4 wall panels. I had this design for making the panels utilizing empty water bottles. What do you think? Will this work well enough to keep in heat and block outside cold air? I wish I had some idea of the R value. Cut 42" long x 36" tall 1/2" thick thick plywood panels. Glue 2x4s around inside edge of each wall panel perimeter, on the wide (4") side.

In Energy efficiency and durability | Asked By Andy Nels | Feb 7 16
Register for a free account and join the conversation


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