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7 Answers

Interior air barrier in walls

Hello again

Thanks to help from those here last year I have built a holiday home cabin/garage close to Vancouver, Canada, (Zone 4C I recall). The exterior is complete and my project this summer is to complete the interior.

Firstly, this 'outbuilding' is not considered by the inspector to be a habitable building, so many 'code' rules don't apply. I believe this means we do not need to install an interior vapour barrier as per the norm in the area. Moreover, my reading on here suggests I should not need an interior vapour barrier anyway. I'm I correct in this assumption?

Asked By Quinn Sievewright | May 13 18
10 Answers

Seal gap between felt paper and interior wall stud cavity?

Hi there,

I'm currently remodeling a house in Austin, and while I have the walls opened up from the interior, I wanted to know whether or not to caulk or use spray foam as a way to fill in the gaps between the sheathing material and the stud walls. In portions of the house there is felt paper for the areas with wood siding, and other areas there is thermo-ply for the brick walls.

Asked By homeowner123 | May 11 18
3 Answers

How to insulate tiny hot roof

I live in Michigan. We just survived six months of snow. It's forecast to be 80 next week. Humidity in summer is very high. Those are the unchangeable factors.
I'd like to insulate the roof in my bedroom closet. The house went on the tax rolls in 1896, when insulation wasn't a big concern for the builder.
I had dense pack cellulose blown into the walls. A pro did the attic over the two-story part of the house; another company blew in cellulose into the roof of the 1 and 1/2 story part. All parts of the ceiling in that section are lath and plaster.

Asked By AZOgram | May 13 18
9 Answers

Residential peak demand questions

I'm sure most of us have read Dana Dorsett's comments on residential peak demand based pricing that is gaining interest from utilities across North America. Those comments always come up in other members comments so while I feel like I have several comments and questions I try not to derail another persons thread too much. I was hoping to start a thread about that subject so I could ask those questions.

Asked By Calum Wilde | May 12 18
38 Answers

How am I doing?

I just finished the first two weeks of monitoring my water heater. It looks like we're averaging ~5.5kWh/day. There's two adults showering twice a day, and two elementary school aged kids showering every few days. The dishwasher runs about 8-9 times per week. My rough estimates puts us at around an average of 20 gallons of hot water per day.

Can anyone chime in with their usage and family makeup so I can get an idea of home we're doing?


Asked By Calum Wilde | May 2 18
6 Answers

Exterior foundation waterproofing

I recently had my foundation wall treated with a spray on waterproofer. I noticed a week later that there were little pin pricks throughout the black layer. Some of the pin pricks you can see concrete through. Is this a typical occurrence or should I have the company spray the wall again? I am mostly worried that it will cause the waterproofing to be defective due to moisture instrusion. Thanks!

[Editor's note: Photo below.]


Asked By Chris Roche | Jul 16 17
5 Answers

Why is there condensation on my cathedral ceiling?

It’s warm outside (80 degrees) and 75 degrees in the inside thermometer. The roof is in full sun all day so it's hot up there. The is nothing except insulation between the ceiling and roof and the condensation only forms along the beam at the peak of the roof inside.

It’s a split level home with a crawl space under the living room and the finished basement is below the upper level kitchen.

I've attached pictures of the space. Or there also in this link.

Thanks in advance for any help you can offer!!

Asked By Candi163 | May 9 18
7 Answers

Retrofitting walls with interior vapor barrier?

My house is in climate zone 6a, has 2x6 exterior walls, sheathed with OSB, with batt insulation, and an interior vapor barrier. Is there any way to retrofit these walls with exterior insulation that won't cause issues as they can't dry to the inside?

Asked By Calum Wilde | May 9 18
9 Answers

Surface 4 low-e... condensation issues?

I'm just about to order windows for a project, and leaning towards spec'ing some of the units as double-pane with low-e on surfaces 2 and 4. My sales rep is trying to get current information on exactly which coatings are available, but it appears to be Cardinal 180 on surface 2 and i81 or similar on surface 4. He mentioned that there was uncertainty about the surface 4 coating because there had been some condensation issues when this product line came out.

Asked By David Meiland | Apr 10 13
22 Answers

Flat roof (TPO over polyiso build-up) insulation guidance

I am trying to figure out the best insulation build up under this roof situation.

- 27'x29' flat roof with 5/8" plywood sheathing.
- There is polyiso over the plywood built up 1/4:12 on all four side to the the center. There is 1/4" of ISO at the edges built up to approx. 3.5" in the middle.
- There is no ice/water or vapor barrier under the ISO. The ISO is covered with 60mm TPO.
- The plywood seams where not tape or sealed
- The ceiling joists are 14" TJI 360 at 16" OC.

Asked By Eric | Jan 17 16
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