🚀 go-pugleaf

We are about to build a 24' x 24' cottage on our lake lot in northern
Alberta. I plan on using 3" steel pipe as piers set in a 6' grid for a
foundation. I want to drill 8" holes, 9' deep (to get below the frost line),
pour in 1 bag of dry redimix per hole and set the 3" pipe in the holes
(after welding a 6' diameter plate onto the bottom of the pipe). I plan on
welding horizontally, 3" pipe onto the piers to form a "checkerboard" to set
the sill and bottom floor joists. I will be using platform framing.

The cottage will be 2 story with the bedrooms on the bottom floor. The
kitchen and living room will be on the top floor to take advantage of the
lake view.

Reason for using pipe is that it is free. The cottage will be in amongst
some nice trees so there is no room for heavy duty equipment such as
backhoes and dozers. Getting trucked in cement to the house location would
mean cutting down some trees which is something I do not want to do.

Can anyone see a problem with the above. I have been told that perhaps the
piers should be 4' apart but that is a lot of digging.