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48 Answers

The differences between mass and insulation

The "I installed more attic insulation and now my AC runs more" thread got me thinking about the mass effect a bit.

Asked By Nathaniel G | Sep 15 14
2 Answers

The joys of insulating...

What is the best way to insulate around the corners of rigid round duct using foil-faced blanket type duct insulation?

Make a "sock" and coax it around the corners and don't worry about bunching?

Snip out pieces and try to form something like an elbow while generally making a mess and wasting time?

Something else?

Asked By Lucas Durand - 7A | Sep 19 14
19 Answers

Options for high R-value above-grade walls (R-80)?

To make a long story short, my above grade exterior walls need to be at an R value of 80. This is to meet Passive House standards for a new residential house in a very demanding climate.

I am currently planning on using SIP's of some sort. But even the best of those only get me up to around R-50 though. Any thoughts on ways to get to R-80 while still being cost effective and keeping the size of the wall to a minimum?

I have found a number of options myself, but was curious if anyone else had thoughts or suggestions to meet such a high R value for a wall.

Asked By Tom Schmidt | Sep 19 14
0 Answers

Thinking fo going Solar

I have reading alot about solar systems. I live in a 40' 5th wheel RV. Now This is what I was thinking of buying.....

6 - LG 305 watt solar panels ( 305 watt output each total 1830 watts ) ( around 75 amps output )
Magnum 5000 watt 24 volt inverter
Schneider (Xantrex) XW-MPPT-60-150V Charge Controller
4 - 6 volt 480ah Royal AGM batteries.
( Plus 3 - 30 amp fuse boxes and a junction box for the solar panels

My question is..............

I am Trying to figure out how many hours per will I be able to runs some devices on solar

Asked By Ron Davis | Sep 19 14
4 Answers

Air and moisture proofing

I am going to be renovating a 1950’s house in Toronto, ON. It’s a 1 ½ storey that we are making 2 storey with adding addition on the back and attached garage. The plan for the 2nd storey is wrap the outside in Blueskin then cover in 3” Roxul Comfortboard IS, Strap and vinyl side. 3 of the 1st floor brick walls are to be left in place, which I also want to cover in 3” Roxul strap and vinyl side, but unsure what to use under it to keep the air and moisture out.

Asked By Dave B | Sep 18 14
3 Answers

Seeking underlayment material for exterior wall shingles.

I own a home built in 1965. It has cedar shingles as the exterior wall surface. I will be rebuilding a section of one wall as part of a project to replace a rotted window.

The problem is that the original construction includes a material that I can't find, and I'm not sure what could be used as a substitute.

Asked By Don Boettger | Sep 18 14
2 Answers

Sheathing at the ridge vent

I have a 12 pitch roof with 24 OC tji rafters and 5/8 deck membrane I have a 1.5 inch air channel between the rafters that vents along a continuous ridge vent. The sheathing sets back from the ridge 2". How do I attach the sheathing membrane at the ridge set back (other than the 24 OC rafters) without impeding the air flow? Is there a metal, inverted 'U' shaped bracket that I can screw the deck to? Left unattached, compromises my shear value and will eventually sag.

Asked By Ron Walashek | Sep 19 14
2 Answers

A layer of 1" XPS foam between fiberglass batts?

I live in MN and am working on a complete interior remodel. The exterior walls are 2"x6" w/ R19 fiberglass batt insulation, some with Kraft back & some with poly on the interior side. I would like to try & at least double the R value, but due to other design constraints would like to keep the additional interior intrusion to a minimum (exterior insulation is not possible).

Asked By Joshua Streblow | Sep 19 14
3 Answers

Insulating and air-sealing a room-in-truss over a garage

Hello,
I am looking for some clarification on insulation and air-sealing, when dealing with room-in-truss construction for a conditioned space over a garage.
I live in Michigan, climate zone 5. I have a 28x36 garage, with 28ft span 8/12pitch "attic" trusses. the trusses have a 2x10 bottom chord and 2x8 top chords with 2x4's at the kneewall. I have a permanent stairwell going to the room in the truss, and I plan to heat the room. I have in-slab hydronic heating on the garage floor.

Asked By Ben Helmreich | Sep 15 14
2 Answers

Looking for guidance on how to downsize in a green way

Hello. Am looking for some guidance. My husband and I want to sell our current home and downsize to something smaller and greener. Our budget is pretty limited, though, so we're trying to figure out what the best options may be. We will likely have to pay a fair amount just to get out of our current mortgage, pay closing costs, etc. Then we've been approved for a 150,000 mortgage and with that we could:

a. buy an existing smaller home, close to nature (though those seem very hard to find in our budget)
b. buy land and put up a modular home

Asked By Jen Yost | Sep 19 14
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