CONCRETE FOOTINGS Forming
concrete walls begin at the footing, I
like to go with a 1x4
cleat that is 24" wide..
this gives me a 21" footing which is over code
for a two story house.. I use a 2x8 as the form
sides.. rule of thumb
is footing should be twice as wide as the concrete wall on top and as
least as deep as the wall
is wide.. so these dimensions will carry an
8" foundation wall.. wider footings are always
better. the
form work is called a ladder
   note bracing on corners the rock pins should be placed every three feet and driven down flush with top of 2x8 they take a lot of pressure... I do not use wood cleats under the footings... The rebar is held up with tie wire to cleats.. I try to keep the rebar in bottom third of footing and at least 2-3 inches above the ground... if you are using a #3 copper wire for grounding in your footing it can be tied to the bottom side of one piece of rebar max 2" from ground... note my 1x4 cleats every three feet STEPPED FOOTING  The stepped footing is used where bearing ground has caused a change in footing elevation.. the minimum overlap is two feet... the maximum drop in elevation is two feet by code... engineered after that.. I use a double ended 10" waler tie with wedges to hold the bottom together You can pick up 1/4" threaded rod for this it works great... this is the simplest solution to holding together this point... some people use a wooden cleat I do not like any wood running through my footings Note the bulkhead.. I run the 1x4 cleat tight to the bottom just so there is no movement When you vibrate it increases the pressure on the sides  footing
intersectionThe steel can turn in either direction.. it is just as strong both ways When building my footings I run my ladders right through the intersection place and nail the adjacent ladder and the cut out the intersection at the end once the elevations are all set Order of building: Measure the number of feet of footing you need and then build your ladders one cleat each end to hold sides together Place your ladders in place measure the distances and cleat ladders together with 1x4 scabs one at each end.. I cut a handful of temporary spacers to hold the forms apart.. Make sure all is square and accurate Drive rock pins to hold forms in place at the end of each ladder Find the highest elevation and start leveling ,...I use a four foot level and flip end to end each time ... the footings do not need to be deadly level but the closer the better... level and drive a nail through the rock pin Once the whole footing is level I use scarp plywood to skirt the inside of the footing wherever there is space between footing and ground... three or four nails in a 8' piece of plywood is enough... this skirting firms up the sides and holds the elevation in place... now I drive the rest of the rock pins home and nail them to sides Go back and cut out all intersections.. lay in your steel and then place your cleats every three feet and tie your steel to the cleats Now lay a 2x4 down the centre of the footing all around and nail it off to the one by four cleats I always use steel in my walls even though it is not called for by code, so I place my 15m (5/8") hooks in at this time and I tie them with tie wire to the inside of the centre line 2x4... I use 16" centres.. my hooks have an 8" and a 24" leg the 24" leg gives me plenty of room to tie off my vertical steel for my wall curtain  You should make sure you have block outs for plumbing.. electrical.. I also find the low spots of the footings and place a drain pipe so no water accumulates beneath floor... do this for footings in centre of building also... Pour and consolidate with a vibrator float it as flat as possible where the form wall plates will sit the rest leave rough.. go back after pouring and clean up any ridges.. clean up overflows while concrete is still fresh this just makes stripping easier once concrete has set up You can cut in a key way but it is not necessary all your rebar works to lock the wall together GO TO CONCRETE FORMING  |