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2 Answers

Insulate Supply Line in Attic?

Hi, I'm trying to get a little more efficiency out of my HVAC system and I'm wondering whether to bother with attempting to insulate some supply lines that are in the attic of a commercial building. The attic is within the thermal envelope but it is unconditioned. The attic is used for storage and therefore has a floor. All the supply lines have been mounted flush on top of the floor and I can feel major air leaks at all the seams/connections. My idea is try to slightly lift sections and apply mastic tape to the seams on the bottom as well as apply mastic to the sides and top.

In Mechanicals | Asked By Kevin Dorsey | Aug 6 12
7 Answers

I Used the Wrong Nails

I am framing a first floor deck and I used the wrong nails. I shot 2" x 0.99 ring nails instead of 2 1/2" common. The floor is 11 7/8" I-Joist with 3/4" Pinnacle sub-floor. I applied plenty of construction adhesive and only attached the sub-floor only one sheet ahead of the adhesive application. My nailing pattern is about 4" to 6" along the perimeter and 6" to 8" in the field. Should I go over it with the correct nails?

In Building Code Questions | Asked By John McCormack | Aug 4 12
2 Answers

Humidity in Basement

Last year we added an addition onto our house located in Nova Scotia on the Bay of Fundy.The foundation is ICF and the header spaces are insulated with spray foam. There is drainage tile around the outside of the foundation. The problem - I'm getting around 4gal of water a day from my dehumidifier in the crawl space! (unheated). The floor of the crawl space is earth/sand/PLASTIC/Sand. There is no standing water and no signs of leakage but the top layer of sand is wet in some areas. There is no ventilation in the crawl space. Any ideas on how I can remedy this?

In General questions | Asked By Chris Harwood | Aug 4 12
1 Answer

An open thank you letter for GBA's help making my house more efficient

To Martin and all at GBA,

Im a home owner (built 2007) 2700 sq ft Colonial in Rockland County NY (Zone 5)

Ive been following various discussions on reduction in energy bills by increasing insulation and sealing the airleaks

By adding 6' of loose blown cellulose to the R38 in the attic (used GreenFibre and machine from Lowes) and filling the ceiling of garage (has fibreglass batts but huge airgap so used the Greenfibre machine to dense pack the ceiling and completely fill the space.
I airsealed the rim joists and top plates/attic as well

In Green building techniques | Asked By Darren Finch | Aug 5 12
1 Answer

Shutting off oil-fired boiler for 16 days in August

I have a oil fired boiler for heating as well as hot water, I will be away for 16 days this month; can I turn the boiler off for that time without causing any damage?

In General questions | Asked By Stephen Nack | Aug 4 12
5 Answers

Does anyone have an opinion regarding zinc strip installation to deter moss?

I have read pros and cons on installing zinc strips to deter moss and lichen. My House is surrounded with pine trees and I have a good amount growing on the north side of my house. Im hoping Martin will chime in with his opinion on this. Is it worth the expense? Will it do more harm than good? Thanks all

In General questions | Asked By Katherine Slufik | Aug 1 12
4 Answers

Venting under standing seam?

I’m in the design phase of a ranch home (my own), 5:12 hip roof, in zone 3, mixed/humid region of the U.S. Since the attic will be used for HVAC, the plan is for it to be unvented. Initially, the roof construction was to be: plywood deck (taped), tarpaper, two staggered layers of ¾ inch polyiso, 2X sleepers laid on a diagonal for venting and a standing seam metal roof.

In Energy efficiency and durability | Asked By Tim Ellison | Aug 3 12
1 Answer


In zone 6/5, attached barn from late 1800's. Timber frame, true 2x3, boards, lap, and then vinyl (I didn't do it). Someone raised it and poured a concrete foundation. Leaving the ceiling / roof out of the equation for now.

Ceiling height code will be a stinker if I build up the floor much so... floating floor (2x4 grid with XPS) over poly barrier. Don't feel like it's enough at the wall edges, concrete "sucking" out the heat Playing with raising the sub floor near the exterior walls, sort like a built in ledge / kick plate, for some layer foil panels. Sounds strange but it'll look nice.

In Energy efficiency and durability | Asked By T Stills | Aug 4 12
11 Answers

Moisture challenges in my basement

My home was built in 1996. Split level, 1040 square feet. No central air or air conditioning.

We have always had moisture issues with our basement. Cool in the basement, on hot days, just as hot upstairs.

Our bedrooms are in the basement, the basement is completely finished however the floor is cement. We thought we sealed it years ago, but apparently not.

We try to control humidity with a dehumidifier however its not economical nor does it work well.

In General questions | Asked By christine hanek | Jul 30 12
3 Answers

Research info on heat wasted evaporating inside water?

I'm wondering if any has come across research documents or done their own research on how much heat goes into evaporating water that's inside, and ultimately whether or not it is a large or small amount of losses. I know of a building with a wash bay that is heated with modines, and am wondering how much of the heat used is attributed to evaporating un-drained water. Maybe there is a way to eliminate the excess water in a more cost effective manner, prior to its next use.

In Mechanicals | Asked By Mike LaCrosse | Aug 2 12
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