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!

4 Answers

Our Larsen truss project near Mount Robson, BC

Jin wanted a picture of the big mountain neighbouring our small project. At nearly 4000m, it is not the highest peak in Canada but its intimidating south face rises nearly 3000m off the valley floor.

For any climbers out there, the dark triangle below and left of the main summit, the 'wishbone arrete,' is the classic route. I had to use a picture from the fall because the peak rarely reveals itself in the winter months. It is so much higher than its neighbours, it seems to have its own weather system...

In General questions | Asked By erik olofsson | Mar 19 13
14 Answers

How do I flash a no-flange window?

I am wondering if anyone can advise or point me to good details for flashing a non-flanged European window (specifically Unilux).

In Green building techniques | Asked By Robert Swinburne | Sep 14 12
1 Answer

Design of a ground loop system for an ERV

I am building a new house near Albany, NY which is region 5A. I plan to have a super-insulated house with an Ultimate Air ERV. I would like to hook up a ground loop system to the ERV which would consist of tubing that is looped around the foundation footing a couple of times which would contain water or an anti-freeze mixture. The liquid would be pumped through a water to air heat exchanger on the intake side of the ERV in order to raise the input air temperature during the heating season. Where can I find design details for a system like this? What kind of tubing should be used?

In Energy efficiency and durability | Asked By Robert Walker | Mar 18 13
6 Answers

Energy retrofit: HVAC strategy?

I'm planning an energy retrofit/remodel of my 2000SF single-story home in Dallas TX, involving substantial insulation upgrades and thorough air-sealing.

In Mechanicals | Asked By Andrew Thompson Zone 3a | Mar 15 13
5 Answers

Window sill flashing detail

I am completing design details on my house and am a little stumped with the details around the window sill. I will be using Vaproshield's wrap and window components along with Intus windows which have no flanges and Ceraclad's fiber cement rain screen system.

I have added several pictures. The wall is a 10 inch SIP with wood inserts to form the window opening. I will use Vapro's 3D corners and membrane to flash the opening then Vapro's sill saver system to form a sloped sill under the window. As there are no flanges this sill system will form good support.

In General questions | Asked By Stephen Carlton | Mar 17 13
7 Answers

Insulation in cathedral ceiling on addition

I have an addition on a balloon framed 1880 house that I am working on. The addition is comprised of three parts: Main Addition (kitchen) which is 11x14 and is in the center with the roof at approx 16' on peak. There are two smaller additions on each side of this kitchen and the roof slope is reduced significantly on each side. There was no insulation and no venting in this structure. I built out the main kitchen area with 2x10's and plan on insulating with R'30 fiberglass and leaving a 1.5 inch area and drilling holes into the two additions to add venting.

In Energy efficiency and durability | Asked By Geoffrey Cook | Mar 17 13
0 Answers

After the flood...A Sealed Crawlspace?

I recently posed a question about a few homes damaged by Superstorm Sandy in New York.Homes are near the coast,but neither experienced flooding for at least 50 years prior to the previous 2 years,this year being severe,flooding the main levels of the living area,causing major material damage,not structural.Both homes are built on crawlspaces with poured concrete foundations with a couple of cast-in-place vents.They have concrete "rat slabs",which I was to find out were actually retrofitted long after the houses were built in the 1950s.

In General questions | Asked By Dennis Dipswitch | Mar 18 13
5 Answers

Over slab polystyrene foam board insulation and clay tiles

We are using polystyrene board insulation for an over slab application. Is 25 psi polystyrene foam board insulation adequate to support one layer 1/2 inch osb board, one layer of cement backer board topped with ceramic tile?

In Green building techniques | Asked By Tim Hatcher | Mar 14 13
2 Answers

Did I get the right spray foam?

Hi. First thank you to the wonderful people who contribute to this forum. I need some advice and hopefully reassurance that I did the right thing. We just had open cell spray foam installed on the roof deck of the attic, in the eves and dormer roofs of our 100 year old house. I thought I had thoroughly researched this before hand but I guess not because today I found a post here that says this is all wrong. I did ask the spray foam contractor why not use closed cell but he said that open cell was the way to go for this installation. We live in Philadelphia PA which I believe is zone 5.

In Green products and materials | Asked By Cherylann Schieber | Mar 17 13
Register for a free account and join the conversation

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