|
| Author |
Message |
rockies
Member
|
# Posted: 14 Apr 2018 19:25
Reply
I was watching the Mike Holmes show where he was fixing a backyard deck/pool enclosure and he used a deck foundation system from Post tech. He said it was the best system he'd ever seen because it installs quickly, doesn't disturb the soil, there's no digging ,concrete, rebar or formwork involved. You can also use their system for docks, cabins, etc.
Canada:
https://postech-foundations.com/
A P312 pile or higher seems sufficient for a cabin, but their engineers will confirm.
Similar brands are available in the US
|
|
Greenland South
Member
|
# Posted: 14 Apr 2018 22:21
Reply
Thermal screw piles, hmm. Sounds like snake oil to me. I've personally used and seen hundreds more screw piles installed in NE BC. Never heard of a "normal" screw pile moving, (up or down) that was driven into undisturbed soil. I don't buy it.
|
|
ICC
Member
|
# Posted: 14 Apr 2018 23:42
Reply
Well, let's go ahead and accept that these screw in piles will prevent frost heaving. They likely do that if the screw plate end is below freeze level. However, they still have the main deficiency that all piers share. That is an absence of lateral stability. In fact, you would be completely safe in saying these screw in piles have less lateral stability than a typical poured concrete pier or even a 6x6 timber. And it is not a DIY item. Read the notes on their site, depending on the soil composition you may still need a geotech soil analysis and it is stated in several places that installation must be done by a certified installer using mechanical equipment. The pile and screw must be pushed down with sufficient force as it is rotated to ensure the screw plate advances through the soil at a rate that matches the design pitch of the screw plate. Otherwise, it will just drill a hole and loosen the earth like a typical auger bit.
I don't know how the approval for code process works in Canada but in the US any similar piles I've had a look at require an engineer to sign off on the design before the code authority will accept them. Of course, if you are thinking of doing piers in the first place you are most likely not bothering with permits, codes and so on.
|
|
beachman
Member
|
# Posted: 15 Apr 2018 07:27
Reply
I have these very same piles for my deck in hard clay soil that freezes quite deep each winter. After three years, the deck has not moved one bit. I have seen them used on this site for cabins with great results.
|
|
creeky
Member
|
# Posted: 15 Apr 2018 17:04
Reply
I used the deck piers for my 10x14 winter bedroom. The build is documented here.
No frost heave. They do rock back and forth in the summer. Winter freeze in is actually appreciated.
But its fast and cheap. Total cost was 15/anchor x 6. I put them in with a post auger. And I put rebar down the front to help pin the building into place. It still rocks. Gets a little tighter every year.
|
|
|
