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8 Answers

Crawlspace Beam Layout

Hi Friends,

Long time reader, first time poster. I'm looking for some feedback on my plans on fixing some floor bounce/sag.

House layout is pretty simple, 62x32 with one corner consisting of a 20x20 slab garage. Floor Joists are 2x10s, spaced 16" on center. They span almost 16'. The house has long been neglected, and the crawl was filled with moisture for years. Poor landscape drainage, washing machine leak, and a dryer vented to the crawlspace led to sagging floor joists and a main beam with rotten ends. Plus plenty of mold.

Asked By alexallo | Feb 16 18
0 Answers

ERV vs fresh air intake

So my HVAC design is looking like I will do a fancoil on each floor.

I'm seriously considering going with an air-to-water chiller for the outdoor unit and a spacepak aircell on each floor, 4 in total.

These units have a 4" round fresh air port that you can program a percentage of fresh air.

Asked By Jamie B | Feb 17 18
1 Answer

Insulating Raised Slab

Alright, so here’s one that I can’t find in the great treasure troves of this site: how to handle insulating my raised slab on our new house. Quick details on the project: climate zone 6, 3500sqft, two story, zip-r external insulation/sheeting (R6), fiberglass batts in 2x6 walls, combination vented roof w/ R60 cellulose and unvented roof with R50 foam, low U 4th surface fiberglass windows, and a combination of slab on grade and vented crawl w/ R48 foam. The concrete will be polished as finish floor in slab areas. Heating is entirely mini-split, no in floor radiant.

Asked By user-6804212 | Feb 17 18
0 Answers

Slab on Grade in Climate Zone 6

Hey all,

So watching a bunch of Matt Risinger, he's always talking about slab on grade builds, and how we have basements in the far north etc. I know these topics have been brought up before.

I'm in Climate zone 6, Toronto. I'm designing a 100sqft satellite building, or you could call it a shed with all the bells and whistles of plumbing, elec, heating etc.

I'd like to do a frost protected slab on grade for this to incorporate infloor radiant hydronic heating. The slab will essentially act as the radiator, and be the base for the Insulated perimeter wood stud walls.

Asked By Jamie B | Feb 17 18
5 Answers

Are 48" Baseboard Diffusers necessary?

Doing flooring and have pulled out the baseboard diffusers from 1959 house. They are 48" long but the hole in the floor is only 2" x 12". Can I replace with a smaller size or is the 48" length helping to spread the warm air around the room? Note that there are 2 of the 48" diffusers along the same wall in the 14' x 17.5' living room.

Thanks in advance!

Asked By MollyV | Feb 12 18
3 Answers

Ice Damming ~ Solutions for this Situation ...

Some time back I've asked a question about my ice damming issue and received some good advice but had difficulty with local contractors; unskilled or untrustworthy. With time ticking and panic in my heart i went ahead and just got my roof resheeted (steel) but at least got all my soffit vents opened, ridge vent installed and the steel sheets installed with 1" to 2" strapping. Ice Damming still occurs, if not worse, and so i'm back for an updated solution to my existing situation.

Asked By Jake Rabe | Feb 16 18
4 Answers

Questions regarding insulating a 1912 double-wythe brick building

We have a 1912 brick schoolhouse that we are renovating in Michigan. We just demoed the entire floor system including joists and main beam due to extreme powder post beetle and moisture damage.

Asked By 5grams | Feb 15 18
2 Answers

Damp proofing for deck pilasters

I have 9 20"x20"x96" concrete pilasters on footings to be used as supports for my deck and the columns supporting the roof over that deck. Some of these are almost entirely below grade while others are primarily above grade. Do these pilasters need any sort of damp proofing to prevent freeze/thaw spalling? This is a new-build that will have appropriate drainage in Denver, CO in sandy/clay soil.

My opposing thoughts on this subject are:

Asked By Tony Arcuri | Feb 15 18
2 Answers

Brick weep retrofit

Quick intro, I'm an architectural & hvac designer for a engineering firm in Ontario. Before that I worked for a carpenter with a knack for great details and learning from mistakes for all my early years. I'm re-insulating an existing 1970's home in Stirling Ontario. See the attached photo for a wall section. I've run into an issue. There are no existing weep holes and from exterior examination, it would appear there is no flashing. I cannot confirm the existence of a drainage space either.

Asked By Yupster | Feb 15 18
3 Answers

Attic access door recommendation

In my new build i want access to the attic space via a kneewall. What options are there that will provide a good seal and r-value?


Mixed Humid


Asked By Norman Bunn | Feb 14 18
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