Plywood and lumber PWF

Foundation

lumber

-preserved wood foundations certification mark “PWF”:

-(chromate or ammonical) copper arsenate

-pressure treated at 700 kpa for 6 hours and then kiln dried

- very toxic fumes and dust

-wash, wear gloves, do not breath dust

Plywood PWF

Foundation

back filling

-basement floor and the upper floor should be in place before back filling begins ..  back filling should not be directed against wall

pit run gravel in layers around the house evenly not one side at a time than a 600 layer of impervious material then 200 -300 top soil

-a plywood strip 300 wide .. cover plate at ground level to protect the polyethylene .15

Plywood PWF

Foundation

waterproofing

damp proofing:

treated plywood is caulked at all joints using asphalt or bituminous material while fresh stick a layer of black polyethylene ..15  to cover the whole wall.. . joints are lapped 150 and caulked .. the polyethylene extends down over the footing to undisturbed soil

-polyethylene is strip bonded at top

waterproofing:

use the same method only spray entire wall first with the asphalt or bituminous material before laying the polyethylene.. . backfill gently to avoid damage to the membrane

-drainage tile set in a bed of crushed rock with crushed rock covering to a depth of 150

- polyethylene under concrete slab or wood floor does not go under footing

Plywood PWF

Numbers

numbers foundation

-footings; concrete or pressure treated wood, concrete on undisturbed soil must have drain pipes at 1200 on centre 60 diameter

-floor: concrete slab separated from wall with a screed board, or wood sleepers, or suspended wood floor

-plywood 12.5 must be caulked to stud and to each other sheet of plywood with a 2 to 3 gap

-holes and cuts must be treated with a non leachable  preservative

-stainless steel nails and staples

-hot dipped galvanized anchours and straps

- sealant must be compatible with PWF and polyethylene .15

-drainage layer 10% fines # 4 sieve and the rest up to 40

-whole excavation to 300 outside the wall covered with 125 granular drainage layer

-sump pump 750 below basement floor surrounded  up to 150 with granular fill, pump or positive gravity drain, location easy access