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11 Answers

LPG infloor heat with HWH with a heat exchanger in the HWH is too expensive to run!

I have the above home on a monolithic slab. ...LPG to run the HWH and a heat exchanger pipe running through the HWH to heat my floor...TOO DANG EXPENSIVE TO HEAT MY HOME THAT WAY! Suggestions on how to make it more efficient would be appreciated. A air to water heat pump? A heat pump water heater with a heat exchanger pipe running through the HWH? A solar system of some sort?

Asked By Ed Jones | Jan 25 15
0 Answers

Mud sill seal

In the FH article about air sealing a mud sill they used a EPDM product. The mud sill was 2x6 but it looked like they used the gasket intended for 2x4 material. I believe the product is available in both 2x6 and 2x4 widths and was wondering why the intended product was not used. If the 2x4 gasket is acceptable it would save some $.
Thanks.

Asked By Robert Brown | Jan 22 15
2 Answers

Insulating solid brick house

Hello! I've been reading this forum for awhile now and there's so much good information about insulating I don't know which direction to head in. I have a 1950s ranch in Michigan that is under renovation. I currently have most of the walls exposed and wanted to know the best way to go about this. It's a solid brick (like small cinderblock?) house with furring strips and 2 layers of drywall on the inside. On the outside I have furring strips with vinyl siding.

Asked By Jeff Hogarth | Jan 9 15
5 Answers

Condensation prevention for houseboat insulation

Hi, this is a revisit of the question about trying to prevent condensation and water damage while insulating, but in this case for a marine houseboat. We are talking a 3/8" steel hull, 1" air gap, with wooden frame and "rockwool" insulation bats just under 6 inches deep, then vapor barrier, wood veneered plywood sheeting interior walls. Vessel will have hydronic radiant floor heat using grooved plywood with aluminum face for the PEX tubing, and engineered wood flooring, just under 8' deck to deck height. A 15 ft beam, and a LOA of 92 ft..

Asked By John Shank | Jan 16 15
2 Answers

Cathedral attic moisture

I have an attic converted to living space where the roof is also the cathedral ceiling. Most bays go from soffit to ridge and are insulated with fiberglass and a foil barrier with a Duravent installed so that there is always an airspace from soffit to ridge. Those bays are mostly fine. The areas I'm having a ton of ice and moisture on the sheathing is where the bays are interrupted and there is only a ridge vent. Should I fill the bays solid with spray foam? Or should I at least foam up the ridge vent from the inside on those bays?

Asked By steven pereira | Jan 13 15
6 Answers

Flat roof assembly in a hot humid climate

We are going to construct a very modern home with low pitched roofs (1/4" per foot on 5 separate roof levels) being constructed of 18" trusses, utilizing Advantech sheathing for the deck, then a vapor permeable fluid or adhered membrane, then rigid Polyiso board varying from a minimum 1" thick to 6" to create the slopes, then Densdeck Duraguard and finally a fully adhered, highly reflective PVC membrane. Underneath the deck, we intend to use 6-8" of open cell spray foam.

Asked By Norman Luke | Feb 8 14
4 Answers

Vapor barrier height and polyiso question — unvented crawlspace

I am looking to convert my poorly vented crawlspace to unvented one. Because I am in Northeast, I also have to manage radon levels, so I am planning on installing 20mil vapor barrier and already have active radon system installed (but not running yet, until I have the vapor barrier)

Question 1: Considering I will be insulating the walls with polyiso, how far up the wall to I attach the vapor barrier? Foundation is cinderblock and is from 3' to 5' high.
Question 2: Do I attach vapor barrier behind the polyiso or on top of it?

Asked By Apolinaras Sinkevicius | Jan 5 15
10 Answers

Not a green area, but seeking advice on HVAC issue, if someone has time.

Need help from Pros here on what to do.

Had an attached closed porch gutted a few years ago. Was never insulated, connected to the kitchen, with an entry door. Had the porch gutted, re-studded insulated, and had a half bath in one part put in, and the other open area just for storage.
They punched thru an old basement window under the porch (was a basement window on that side of house until the old porch was added on decades ago, but was boarded up). Under the porch is the ground, dirt. the siding does go down to the ground on the porch.

Asked By Dave Mac | Dec 29 14
1 Answer

Crawl space rehabilitation using vapor barrier, rigid foam board and cellular concrete

Whoever coined the phrase "Do it Right the First Time," had it correct.

I have a technical question concerning how to properly rehabilitate a crawlspace using the correct materials and procedures.

Asked By Thomas Trible | Dec 27 14
8 Answers

To install engineered hardwood flooring over a basement slab, can I use (2) 3/8" CDX plywood over 1/2" XPS?

QUESTIONS: Can I use 2 layers 3/8” CDX Southern Pine plywood (joints staggered, glued & screwed together, but NOT mechanically attached to the slab) over 1/2" XPS? Whether I install the plywood sheathing over a vapor-retarder or rigid foam insulation, is CCA treated plywood necessary in either case? Which installation method (e.g. rigid foam or vapor-retarder) do you recommend in view of my concerns below?

Asked By Kevin Peters | Dec 11 14
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