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5 Answers

Concrete slab reinforcement: M100 vs. F100 fibers: finish and strength

My concrete contractor has 2 fiber choices for the slab pours : M100 and F100 from BASF. Both are polypropylene fibers, the difference is the size.

Officially M100 is only to be used to prevent shrinkage cracking. Unofficially it has been used (with apparent success) to replace light wire mesh in slabs poured in Southern Ontario. Concrete contractors prefer it when a smooth finish is requested as the extra fine fibers make the slab easier to finish.

F100 is a larger fiber, that is approved by BASF to replace light gauge wire mesh. There is no question this is the robust choice.

Asked By Mai Tai | Jun 25 17
3 Answers

Dense packing a flat roof

Hi Recently I've been wanted to upgrade my insulation as my house was built in 1975 and I'm sure the insulation is not pulling its weight.. I got an estimate from an insulation installer who said that they can take of the fascia board vent screens and put in and blow in cellulose and pack it in in the flat part of the roof. I asked him about moisture and vapor issue and he said that it wouldn't be an issue. Although I am a bit hesitant on this as I'm sure it will be an issue down the road. I was wondering if some of the experts can lead more info on this situation.

Asked By Beach13 | Jun 25 17
15 Answers

Frost wall foundation details for stone and siding construction

I am planning a slab on grade build (24"X8" footings, 4' deep, with 4'6" frost walls). I am having issues with the location of all the sub components on the frost wall width, specifically on the stone detail wall (front wall only).

Asked By Mai Tai | Jun 18 17
2 Answers

Spraying vapor barrier paint on open-cell foam

Hi,

I want to use open-cell foam on a new project and am trying to meet the IRC guidelines. The insulation installer suggests spraying vapor barrier paint directly on the foam. I have read previous research on GBA that found this ineffective. However, would it also be detrimental to the performance of the foam, or would it make no difference?

Thanks,

Josh

Asked By user-6868809 | Jun 16 17
2 Answers

Why is the "Green Homes" section blank?

When I click on section tab at the top, the page that I'm directed to is blank!

Asked By Cm Mm | Jun 15 17
4 Answers

Adding exterior insulation to 100 yr old house - added risk for rot where framing contacts foundation?

Going to add exterior insulation (spray foam likely) over 1 layer of siding. The house has a rubble foundation with no capillary break between the foundation and the framing. The ends of the floor joists are embedded in the foundation.

The house had 2 layers of siding. I've removed the outer layer to expose the inner and found the inner siding and sheathing rotted at the bottom of the wall where it covered the band joist and sill. See pictures. Luckily, the joist itself is in good shape.

Asked By TIM LANGE | Jun 14 17
8 Answers

Zone 1 (Oahu) uninsulated house, but don't want to use A/C - DIY

Hello, I'm in a Zone 1 climate, leeward (west) Oahu, Hawaii. My house is a mid 1980's construction, double-wall but with no insulation, anywhere. AC is via window units, installed in either windows or wall, but I really don't like using them as even if it's just one AC, room closed up while habitated, say the bedroom, it will raise the bill by $~70 for the month and is not pleasant anyways (noise, cycling etc). I've looked at several sites and this and green building talk seem the most professional in their engagement, and have some of the same posters it appears.

Asked By 73Greencorvette | Jun 12 17
8 Answers

Has anyone ever heard of homeowner insurance canceling your policy due to bees under your siding?

We bought our house 2 years ago in Louisiana and last year, a swarm of honeybees from a neighboring beekeeper choose our home and made colonies. We've had 2 professionals come look and they say it's likely we have at least 3 colonies based on the size of activity and 3 different entry points. So the suggestion was made to contact our insurance company to see if we could get help removing bees and honey and repairing siding that would need to be removed,which is practically the entire back and side of our home.

Asked By Vinysgirl | Jun 9 17
2 Answers

Turning a traditional bathroom into a wet room.

Anyone have suggestions on how to waterproof the entire floor to drain properly....my space is limited and my drain pitch is maxed......fyi this is in the basement.

Thank you in advance

Asked By Ogmrfixit | Jun 3 17
13 Answers

Floor above unconditioned space

Hello
Firstly thanks for the feedback on my previous roof assembly post. This question relates to the floor of the conditioned area (ceiling of a garage/carport). Thankfully no ducts, just wires and plumbing in a few locations.
By way of background, its climate 4C (near Vancouver, Canada) and a small building used as a holiday home, not fully occupied in Winter. The occupied conditioned space will sit above both an unconditioned garage and cantilevered over a carport.
Designers build up from conditioned side down:
- ¾ OSB T&G
- Poly sheet
- 9.5” I Joists on 16” centers

Asked By Quinn Sievewright | Mar 29 17
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