Set it so that the 8 inch 20 cm mark on the body of the framing square intersects the line for the tail cut.
How to jack up roof rafters.
The roof is hipped so the ridge is only.
Step 2 hang a plumb bob from the nail and mark the point where it touches the joist below the rafter using a pencil.
Remove the jack quickly and set the iron onto the entire beam.
This will provide a 4 in 10 cm birdsmouth cut.
Tap a small nail into the side of the rafter at that point.
Jack up the rafters by giving one inch space between them this will allow the roof to move with it without cracking.
Use the body long side of the framing square.
How to fix a sagging roof line.
However this should be done very slowly and carefully.
Then lower the jack down a little at a time so that the metal can take the weight of the roof.
Check the ceiling for sagging by attaching a string on one end of the beam and run it along the.
Place the jack back underneath the beam but this time under the iron piece.
I am tempted to install the new rafters with the crown down to reduce the jacking required.
Screw a 2x4 about 12 long.
Drive the remaining carriage bolts into the two by six rafter and tighten them all up.
I can jack against the ceiling joists over a bearing wall below.
Rotate it 180 from how you ve been using it so the right angle is pointing up.
The first step is to the basement first.
Position the body of the framing square on the rafter.
It may take several weeks for the rafters come back in their original position.
Measure the length of one of your rafters and mark the rafter at its midpoint.
Straighten rafters can be done easily by jacking them one over the other.
After your floor is straight it is time to concentrate on the next floor s ceiling.