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25 Answers

Insulation retrofit

Looking for some advice on a smallish rehab project I am about to start. I've read many of the great articles and Q&A discussions here, so I think have bit of direction...but as I am novice, I am interested in some feedback before I moved forward.

Asked By Jeremy Kachejian | Jan 12 17
4 Answers

Insulating vaulted ceiling

I am building a tiny house / cabin and have 2x6 joists my current plan is to use 1/2" osb on the deck covered with synthetic underpayment then a radiant barrier on top of that follower by 2x4's strips to gain 1.5" of air space then attach my metal roofing to that. On the underside I was going to do closed cell spray foam for a sealed roof the. T&G pine over the insulation are there any faults with this plan? I read in a article I should install drywall with a vapor retarding paint then the T&G over then any reason why? Also plan on installing a lunos e2 HRV.

Asked By Devin86 | Sep 5 17
6 Answers

Anchor bolt issues: bolts too low or too far, need alternatives after pour

First casualty of a custom build : my anchor bolts are not ideal, with some placed too low in the wall, and a few placed too far forward to grab the sill plate per current design. Apparently even after I insisted they placed the bolts in the outside third of the wall (their "siding" position,as i was told), where they really should have been placed on the inner third of the wall. Even though I caught it before the concrete was cured, moving the bolts to an "acceptable" location made a few of them too low to provide enough thread to bolt to.

Asked By Mai Tai | Sep 4 17
3 Answers

Multiple conduits from house to garage (gas, electric, low voltage) : is there a separation rule?

I am pouring my frost walls tomorrow (London, Ontario), and I will be adding an 8" sleeve 3' down in both walls so I can run (3) separate 2.5" conduits from the house to the garage (about 20' between house and garage). Things I may be running through the conduits:

1 Natural gas
2 Electrical (to feed a 100 amp garage panel)
3 3/4" cold water pex line (to feed garage taps and utility sinks)
4 1/2" pex hot water line (to feed the utility sink)
5 (2) 1/2" pex lines (supply and return) to supply the in slab heat from the main water heater

Asked By Mai Tai | Aug 30 17
9 Answers

Electricians: Are copper main water lines still used for the main house ground?

I will be running my main water line under the footing very soon, and although I have selected Pexa for the main 550' run, I still have the option to connect it to a 12' piece of 1 1/2" copper pipe to make the through slab section/main ( I am just running a 3" abs pipe under the footing right now to allow connections at a later time)

Asked By Mai Tai | Aug 22 17
22 Answers

3/12 pitch roof insulation

Hi all.
I sent a question and got a reply on a 2/12 pitch roof.

I have an architect working on my plans now. It is a single-slope roof at the widest part (of 32 or so feet).

I originally was going with 3/12 pitch, but he thought 2/12 would be a lower roof at the tall end, so I said fine!

Now, looking at the problems with 2/12, I asked to go back to the 3/12 pitch. So: If I go 3/12, would I (or should I) use R-60 fiberglass? It will have 24 in. parallel trusses.

Would I still need a cupola? (Zone 6, lower Michigan.)

This is TMI for my small brain...


Asked By Robertsoave | Aug 19 17
5 Answers

How would homeowners find a truly green contractor?

Where or how would a homeowner be able to find a licensed contractor knowledgeable in the practices and topics discussed on this site, or even green building and healthier building materials in general? Had hoped to be moved in before the holidays and I'm told there is roughly only one month or less of work remaining to be done... but I can't even find a contractor or subcontractors to do it. Maybe I'm searching in all the wrong places? Any advice or help would be immensely appreciated.

Asked By Natasha Reeves | Aug 21 17
6 Answers

Ridge vents: are they susceptible to snow drifts and driving rain?

My current design incorporates ridge vents with simple gable roofs (both house and garage).

It seemed to be both the aesthetic and performance choice. I will be using standing seam steel roofing, which seems to have a very water tight ridge vent design.

Asked By Mai Tai | Aug 17 17
4 Answers

How do I solve a backdraft issue in an airtight house with a three flue chimney?

There is a wood stove in the basement, a fireplace in the living room and a BBQ place in the kitchen. Each has their own flue. When I light a fire in the fireplace, it draws air back into the house through the BBQ flue. If I open a window in the dining room, it stops drawing air down that flue. Unless there is a wind out of the North West, then it is still a problem. Smoke from the chimney flue goes up and out and then gets sucked back in the BBQ flue and comes out in the kitchen.

Asked By Luke Thompson | Jul 30 17
14 Answers

AC register condensation: Not enough ridge for adequate ridge ventilation?

I'm living in the Houston area (zone 2) and noticed water leaking from some AC registers yesterday. The home is 9 years old, 300 sq ft.

The flexible ductwork is insulated.
The register boots are insulated, and the insulation has a lot of mold. (pic attached)
There is significant water in the attic on the blown in insulation around the duct boots: not damp, really wet.
I do not think the register boots are leaking, but I guess they could have small leaks.

Asked By Mark McFarlane | Aug 14 17
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