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52 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

Best time to stop construction for winter..?

It looks like our builder has overbooked himself and will very likely not be able to put the house under the roof+finish exterior before winter. We understand that one could continue to work in winter, through all stages of construction if additional measures like heating tents are used when applying exterior EIFS stucco. So the problem here has to do with management of resources and time rather than the physical limitations. Nevertheless, we face these choices:
1) don't start until next spring (bank funding would be lost and we'd have to re-apply)

Asked By Lucyna de Barbaro | Sep 20 14
23 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
3 Answers

Thinking of 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
1 Answer

Woodpeckers, Stucco + Exterior Foam with Rainscreen

Our client has requested to change the exterior wall cladding from from smooth panel cement board to acrylic stucco mainly for aesthetic reasons (eliminates corner trims, battens, etc.). Woodpeckers are a real concern in the area and when they knock on stucco with foam behind it sounds hollow so they keep digging.

First up, the proposed wall assembly: (BC Interior Climate Zone 6)

5/8" GWB
Membain vapour retarder
2x6" Studs @ 24" of
R22 Fiberglass Batt Insulation
3/8" OSB Sheathing
Tyvek WRB
2 Layers of 1" Type 2 EPS with staggered joints and taped seams on outside layer

Asked By Brett Sichello | Sep 20 14
1 Answer

Insulating Cantilever Space Containing Water Pipes Zone 4A No. VA

I am wondering what is the best way to insulate a cantilever space containing hot/cold supply pipes and a bathroom exhaust vent. Above the cantilever is a bathroom, below is the entrance to my house and on the inside another bathroom. Currently there is only fiberglass, no blocking, no foam, no sealants. The pipes have been there since 1984 and since I live in a middle unit townhouse they will not be moved.

Asked By Alex Chandler | Sep 20 14
0 Answers

Fresh air intake filters

Hello,

I have the RecoupAerator ERV that I am in the process of getting installed. I have some sheet metal/duct people coming next week to give me estimates on installing the fresh air intake duct that will terminate thru an exterior soffit.

The RecoupAerator comes with MERV 12 filtration material inside, but I am wondering how to filter the air at the entry point into the fresh air intake duct. A simple insect screen there might still let small bugs and such into the the duct work where they will decompose.

Asked By Venkat Y | Sep 20 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
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
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