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9 Answers

Are holes in exterior plywood sheathing necessary?

We are building a new home on the west coast of BC. Our framer has placed large diameter holes in the exterior plywood sheathing saying this is necessary to meet code and allow the exterior to breathe. Our concern is that when other protective layers placed over the sheathing break down over time (plastic and tape and glue only last so long) we have a welcome entry point for water, rodents, carpenter ants ect. How does this practice fit into an 'airtight' home??
We are not builders but can't find anywhere noted that these holes are necessary. Thoughts, advice or comments appreciated.

Asked By Frances Bucinel | Feb 10 16
7 Answers

GSHP and an endless pool

We have slowly been renovating our 115 year old, 2200 sq ft farm house over the past 12 years and live in northern Michigan (climate zone 6). This year we are replacing the 60 year old aluminum siding and roof and upgrading the walls to r30 and the roof to r60. We are also adding a 2425 gal endless pool/spa to the outdoor covered porch. I understand an outdoor pool in northern Michigan probably doesn't fall into the category of green building but it will definitely be fun!

Asked By Ryan Knight | Feb 9 16
0 Answers

insulating walls and ceiling for barn workshop...

Hi Folks,

I am in the process of building out my 1350 sq ft barn for use as a sculpture studio (i do mostly wood and metal fab). I use the space year round, and before insulation I can barely keep it in the low 40s with a 35k BTU pellet stove running 24/7.

The barn is sided with 1x12" eastern pine board and batten (all dims are actual not nominal) The roof and walls are 2x6 rough hemlock or eastern pine. Between the b&b siding and the studs is a very cracked/UV damaged poly barrier.

Asked By Benjamin Jones | Feb 11 16
3 Answers

Duct manifold for a stand-alone ERV

I'm trying to figure out the best way to install my ERV ductwork. I don't have a forced air system, so each supply or exhaust will have it's own duct. I have seen the typical trunk/branch method, but a manifold system seems easier. Does anyone have experience with building a manifold system for mechanical ventilation? I will have three exhaust ports and four fresh air ports. I've looked at the Zehnder systems and they look pretty slick, but I cannot afford the price. I am leaning toward Thermaflex ducts, which are high quality flexible ducts usually used in commercial applications. Thank you!

Asked By Adam Emter | Feb 9 16
1 Answer

Gasket material for Seiho vents?

I am installing Seiho vents on metal siding. Does anyone know of a good gasket material or similar product to keep water from making it behind the vent? My thought was to cinch the vents tight to the metal and sheathing with screws and include a gasket and bead of silicone around the edge.

Asked By C. Maglio | Feb 11 16
36 Answers

Best way to fix insulation problem in cathedral ceiling? Please help!

I built my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

Asked By Aaron H | Jan 31 16
4 Answers

Do I need to install rigid insulation in the bottom of a walk-in refrigerator before I install tile?

I am being hired to remove the failing metal floor and install quarry tile in the bottom of a commercial walk in refrigerator. The existing floor has 4" of insulation, then plywood and then metal floor on top of the wood. I believe the existing insulation is in very poor condition and possibly wet and I am planning to remove all of it. This is in a restauraunt in southeren California which is on the second floor of a commercial building where there is a structural slab as the foundation and there is occupied space on the first floor below.

Asked By Jim Jelinski | Feb 10 16
6 Answers

I have a crawl space with cold joints that are inadequately sealed and ooze water. How can I seal them?

I would like to do it healthfully and effectively so I don't have to be concerned about water intrusion in the future.

Asked By Kevin Krafft | Feb 7 16
3 Answers

Effects of 2" to 3" PVC dry drain pipes through crawl space

Good evening. I have a 2,600 SF home that has 900 SF crawl space under half of it. The builder placed all the overflow type drains (next to water heater/washer, next to my mechanicals, etc, to run to daylight into my far yard. These don't have water traps because they run to daylight I suppose and rarely if ever have drain water in them.

My house does not use A/C and in winter we currently use a large indoor wood burning stove and supplement cold rooms with electric oil radiant heaters, as-needed.

Asked By Andy Nels | Feb 11 16
1 Answer

Zip panels as a WRB for SIPs?

We are building our home with 8.25" SIPs made from OSB and EPS foam. I have been considering using a fluid applied WRB like one from Prosoco, Stoguard, Tremco, or the fluid applied Tyvek brand. I'm reading varying reports of their durability and have been turned off by their steep prices. For instance, based on estimated coverage, the Prosoco Cat 5 would run me around $1.44 per sq ft. Surprisingly, sheathing over the Sips with Zip system panels would be around $0.62 per sq ft.

Asked By Brian W | Feb 10 16
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