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2 Answers

Mold on wall sheathing?

We are having a new house built, currently being framed. I stopped by after work today and saw what looks like it could be mold on the brand new wall sheathing. It could also be some sort of ink I suppose, since some lettering on other boards were a very similar color. I was just hoping to get some optnions from the board since you all appear more knowledgeable than me, and possibly save myself from calling out our GC on a non-issue :) Thanks in advance!

In General questions | Asked By Jon Martin | Aug 21 15
4 Answers

Attic ventilation

2,100 sf ranch style house on a slab was flipped by contractor prior to our purchase in December 2014. Gas hot air furnace and HVAC unit, new in attic, replaced outdated equipment. Flipper added blown in insulation in attic to R38 and when testing of ducts failed -- the ducts were brought up to code. Living space was also evaluated for air tightness and leaks were resolved.

In General questions | Asked By Ray Gendreau | Aug 21 15
5 Answers

Net metering

I was on another site and heard something. Now I dont know if it is true but I got to thinking.

What I heard is that in Michigan the utilities want the net metering customers to be charged full rate for all the electricity used and then be given a credit of 4 cents per KWH for what you produced. In effect you dont get to use what you produce but share it with the grid and are paid 4 cents per kwh, Then you have to buy all your electricity at the standard rate.

In General questions | Asked By Robert Hronek | Aug 20 15
3 Answers

Split air line set deformation question

Hello All,

I'm installing my my own split-air system with three zones. One is an 18k ceiling cassette that has a 1/2" and 3/8" line-set. Despite my best efforts, the 1/2" copper got deformed when making a corner. It's not kinked, exactly, but definitely deformed. So my question is, will it work with the deformation or have I botched the line-set, altogether? I've attached pictures.

In Mechanicals | Asked By Scott Mcllarky | Aug 20 15
7 Answers

Detailing stoop slab: concrete to wood

I am building a new house which will be clad in full-thickness natural stone veneer. A stoop slab just outside the front door will be poured on top of a cold room that's part of the foundation.

My concrete contractor, of course, wants to pour the slab right against the rim joist. That's not going to happen. But what SHOULD happen?

With the masonry veneer, the wall above includes a 1" air space--should I have the guy leave the 1" also between the slab and the rim? How would I ensure proper water drainage out of that space?

In Green building techniques | Asked By Andy Chappell-Dick | May 18 13
9 Answers

How to I properly insulate and seal an HVAC plenum through a garage slab?


I have a difficult situation. I had to completely gut the existing HVAC system in my 1991 house due to numerous major issues (flex tubing like Swiss cheese facing into the plenum, kinks, leaks, a branch off the end of the trunk, returns in the wrong place, missing registers in some rooms, too many in others, etc. After ripping everything out in the house and basement, Now the trunk is all metal, sealed, insulated, properly sized, reduced correctly, dampers on all branches, etc However, I found another problem.

In Energy efficiency and durability | Asked By Jeff Richardson | Aug 10 15
3 Answers

Furring orientation over exterior mineral wool panels

Our office (architectural) is considering using exterior mineral wool with furring strips to create a rain screen. The assembly would be like this, from interior to exterior:

5/8" GWB painted w/ semi-permeable paint
2x6 studs w/ r-21 fiberglass batt insulation
1/2" plywood sheathing
Henry Blueskin WRB (fully adhered housewrap w/ 29 perms) which would double as air-barrier
2" Roxul Comfortboard IS
1x furring strips
vertical wood board siding

In Green building techniques | Asked By Daniel Stewart | Aug 17 15
13 Answers

Tape exterior XPS insulation and housewrap?


Long time follower first time poster.. I have learned so much from this site and appreciate all the knowledge you people share.

We are building a tight house in zone 6 Ontario. The wall stack from inside is as follows:

2x3 uninsulated service wall
2x8 stud wall filled with dense pack cellulose
Cross bracing for lateral strength
2" XPS on exterior
Tyvek WRB
Furring Strips (airgap)
Hardiboard Siding

In Green building techniques | Asked By kyle lamont | Jun 19 15
9 Answers


I know this is a topic that has been talked about a lot, but I do have a question we are mulling over in designing our house.

I have been pricing materials and it seems that both ICF and SIPS are going to cost relatively the same. (We are doing labor ourselves.) With the ICF we were going to get continuous R value of 24 and no air leaking or thermal bridges. We were going to bring this up to the roof where we would use SIPs that are 6 1/2" for an R40. We were then going to either dense pack below the sips or add another couple inches on top to try and bring it to around R60.

In Energy efficiency and durability | Asked By Jordan Schiele | Aug 18 15
6 Answers

Insulating a wall with loose and blown-in foam

We are in Zone 6 . Most builders here recommend the code which is 2x6 walls with R20 loose insulation plus optionally 1" of rigid foam outside of the plywood . One builder recommended R-20 loose insulation and 1" of blown in foam between the loose insulation and the vapor barrier. He said it creates a better seal.

I haven't seen this method, is it a sensible alternative to what the other builders are recommending?

In Energy efficiency and durability | Asked By John Ball | Aug 19 15
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