Q&A: A Forum for Green Building Experts and Beginners

[Click map to enlarge]

drawing of climate zone map.gif

Advice can depend on climate -- Please specify in your question.

Please register for a free account or sign in to ask and answer green building questions.

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!

Ask a Question >
4 Answers
Attic Air Sealing

Hello,

I was wondering if there was a way to easily air seal an entire attic?

The attic is vented and unfinished with fiberglass batt insulation. The insulation and air gaps are located beneath a wood plank floor that has been nailed down. If I wanted to air seal the traditional way I would have to pull up all of the floor boards, the insulation, and then find and seal all of the gaps. Is there an easier way to to air seal over the gaps, existing insulation and wood floor?

In General questions | Asked By Graham Mink | Feb 6 10
17 Answers
Sizing exhaust only ventilation?

I am roughing in plumbing and electric and need to add ducts if we choose to use an HRV which is what I had originally planned. The house we are building has radiant floor heat in the basement and an outside air supplied sealed fireplace on the first floor so no ducts yet. Some other costs have exceeded estimates and I am thinking of using an exhaust only system to ventilate the house (Northern Michigan approx. 8000 HDD, R-40 walls, R-60 roof, hopefully fairly tight, about 2400 sf).

In Mechanicals | Asked By Donald Lintner | Feb 1 10
3 Answers
Discussion topic : Why we should consider simplicity during the design phase.

I came across a posting from Robert Bean's Healthy Heating site. I took a HRAI course that he taught on Radiant Hydronic when I started thinking about how I'd heat my house. The points he makes are somewhat aimed at hydronics designers but can apply to the whole house as a system too I believe.

In Energy efficiency and durability | Asked By Andrew henry | Feb 5 10
2 Answers
Dense-packed insulation

Hi,
I've worked with blown cellulose a few times, in attics and such. Each time I rented a blower from a big-box store. However there seems to be no provision for dense packing with these machines. Where do you find /rent dense pack machines and find good usage directions? Thanks.
Scott

In Green building techniques | Asked By Scott Mangold | Nov 25 09
3 Answers
To those who attended the 2009 Passive House conference.....

The Passive House Institute-US had made available for viewing and downloading the presentations made at the conference. I'm glad they did this-there was a lot of great information and seeing it again does make one re-energized!

http://sites.google.com/site/phconferenceoct172009/home

Derek

In PassivHaus | Asked By Derek Vander Hoop | Feb 4 10
6 Answers
Tradeoffs of passive heating and cooling strategies

Has there been any conclusive research done on how to negotiate the tradeoffs of passive heating and cooling strategies based on climate and location? Most specifically, should things such as light-colored roofs and minimal east- and west-facing windows be done in all climates in the U.S. or does it depend on whether or not your climate is predominantly heating or cooling. I have heard both positions from different building science experts.
If anyone has numbers to back up their opinion, that would be greatly appreciated!

In Energy efficiency and durability | Asked By Karen Leu | Feb 3 10
5 Answers
I have a 4-year-old home I built myself.

I used blown-in fiberglass up top. I went up the the attic to look lately and found that it has settled about 4 inches. I would like to use some cellulose to blow in on top of the old insulation.
Yes or no? Please help.
Fiberglass or cellulose?

In General questions | Asked By Ryan O'Dell | Feb 1 10
2 Answers
Does a hydronic air handler provide greater efficiency than a highly efficient natural gas furnace?

I have not been able to find any information showing measured efficiencies of hydronic air handlers. For one, hydronic air handlers seem hard to come by (unless I'm looking in all the wrong places). The only reputable manufactures to offer them to my understanding are LifeBreath and Lennox. Neither manufacturer provides any information regarding how the efficiency of a hydronic air handler compares to a natural gas furnace or any measure of efficiency at all.

In Energy efficiency and durability | Asked By Mike Maraghy | Feb 2 10
4 Answers
Outdoor air supply for woodstoves...

Assuming a tightly constructed home (2 floors each 1400 ft2 and exhaust only ventilation) and a woodstove in that home with a properly constructed chimney...
Outside air direct to combustion chamber or should the stove pull air from the house?
What is the difference between a sealed combustion gas boiler (for example) and an airtight woodstove with direct outside air supply?

In Mechanicals | Asked By Lucas Durand | Jan 31 10
1 Answer
I live in Florida. The garage is becoming a family room.

The room will need to be insulated. With foam board will I need a plastic barrier?
Then wood frame with sheetrock.
Thank you for reading.
Any advice will be helpful.
Doug

In Energy efficiency and durability | Asked By Doug Haisch | Feb 1 10
Register for a free account and join the conversation


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