Community: GBA Pro help

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!


7 Answers

Stone foundation floor insulation

We have purchased a 100yr old home in central Massachusetts with a stone foundation. The basement is used solely for the purpose of holding the heating and hot water systems. We are in the process of addressing significant water problems. To date we have installed sump pumps, air exchange ventilation system, dehumidifer and we have begun parging the stone walls with hydraulic cement. Long term plans are to regrade the exterior and divert roof water away from the building. That being said we believe the basement will never be entirely dry and the cost to do so is prohibitive.

Asked By Michael Peluso | Oct 9 11
2 Answers

ERV/HRV installations using forced-air space heating ducts

I am a HERS rater and EE building consultant. 40-50% of the new constructon I see utilizes an ERV/HRV for whole house ventilation. Of those, (roughly) half of those are installed in houses using ductwork for space heating and/or cooling. Of those many have the ERV/HRV houseside ports ducted into the return side of the duct. My question is: How reliable is the airflow strength of the ERV/HRV when the ERV is called to run, but the air handler unit fan is not running.

Asked By Kevin Hanlon | Oct 7 11
7 Answers

What is the best approach to waterproofing stone foundation walls?

We have a 100-year-old home, and are introducing exterior foundation drains to help mitigate water infiltration in basement. What is the best approach to waterproofing stone foundation walls? Spray-on products?

We will be excavating to expose entire foundation wall, introducing perforated pipe to daylight, creating a drainage plane against wall with aggregate. Given the porosity of the existing stone foundation, we'd like to consider a spray on or paint on waterproofing application. Looking for advice.
THANKS!

Asked By Robert Post S.E. Pennsylvania Zone 4a | Sep 25 11
7 Answers

Airtightness of wall systems

Can anyone produce a list comparing the average airtightness of the most popular wall systems?, tyvek and fiberglass, airtight drywall and fiberglass, taped EPS and fiberglass, sprayed caulk and fiberglass, same where applicable w cellulose, open cell, closed cell foam? I know everyone has their favorites, and there are a million variables,

Asked By william goodwin | Sep 25 11
3 Answers

Vented vs. non-vented roof

I live in zone 2A north of Lake pontchartrain. I am building a gable house with living area upstairs. The roof is galvalume with a metal ridgevent. The ceiling in the upstairs living area is cathedral then it goes flat. Should I go to the trouble of providing air space under the roof sheathing or close off the ridge vent with closed cell foam and foam the underside of the sheathing?

Asked By dwight foreman | Sep 2 11
11 Answers

How will the use of a Thermastor dehumidifier affect the temerature of a superinsulated basement?

Facts: The house in question is (3) story 4,800 sqft, designed with R-43 walls, R-60 ceiling, R-29 basement (where sub grade, the rest is R-43 at walk-out) and sub slab insulation is R-19. The slab is to be 4-inch. The location is Newbury, NH (Zone-6) I would like to address summer time humidity concern by installing a Thermastor ("Sante Fe") unit in the basement Utility Rm. My son, who works for Thermastor has a similar set up in his Madison, WI house and he observed 70% humidity at the 2nd floor was reduced to 50% within a day (maybe less).

Asked By Harry Seidel | Aug 25 11
5 Answers

Is it a good idea to use a drainage plane behind vinyl siding?

I am residing my home and installed Tyvek for the weather barrier. Is it also good to use a drainage plane material to control the water intrusion from the vinyl siding?

I have only a 1/4 to 3/8 of an inch that I could add to siding depth because of window depth. What type of drainage would work best if needed or used mat,dimpled or fiber weave. No one in my area is using this method. I live in SE. Wisconsin.

Thanks for your advice.

Asked By Deryl Dew | Aug 24 11
3 Answers

Is some roof venting better than none?

I read with interest the article on roof venting by Joseph Lstiburek in the Sept. 2011 issue.
I am halfway finished with a mountain home in southern Colorado, climate zone 6. I will
insulate soon. I had planned to vent as much of the roof as rasonably possible and have

Asked By John Reeder | Aug 15 11
7 Answers

How about sealing and insulating both the roof deck and the attic floor?

I just read Joe Lstiburek's excellent Crash Course in Roof Venting. It caused me to have an unorthodox idea about which I seek your opinion: sealing both the attic floor and the roof deck. Please read on before you dismiss me as nuts.

Asked By Robert Nachtrieb | Aug 12 11
2 Answers

Please help with my board on board external wall design

I'm in middle Georgia - zone 3 mixed humid climate with 2565 heating degree days, 1948 cooling degree days. I'm building a 1600 sf house on a slab on the last lot of an old community of board on board cedar patio homes. The inner boards were 1x8" and the outers 1x6" overlapped 1" so the widths all looked the same.

They were nailed directly over let in blocking with no sheathing.
They suffer from air infiltration and require repainting every 4 to 5 years.

Asked By Jay Apalachi | Aug 13 11
Register for a free account and join the conversation


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