Sagging roof rafters can lead to serious problems with the entire roofing system. If you notice that there is a sag in your roof, chances are you have a problem within one, or several, of the roof rafters. Broken, or sagging, rafters will directly affect the rest of the roofing system causing more problems like caving in, water leaks, and even walls to bow out. Repairing a sagging roof rafter is not a hard project, but it can be difficult if there is not easy access to the rafters.
Tools and Materials Needed:
- Hydraulic jack
- Reciprocating saw
- 1/2 inch thick angle iron
- Carriage bolts
Step 1 – Determine Extent of Damage
The first step is to find out how many rafters are sagging and if anything else is damaged. You may find that several roof rafters are in need of straightening and that some of the sheathing must be replaced. It is important to fix the sagging roof rafter first before doing any other work to the roof.
Step 2 – Set Up Jack
The easiest way to straighten a sagging roof rafter is to jack it into position. The trick with this process is to do it very slowly. It may take a few weeks before you get the rafter into a position where it is straight again. Move the jack in increments of 1 inch to allow for the roof to be able to move with it without cracking.
Step 3 – Drill Holes in Angle Iron
To keep the roof rafter from buckling again you will need to secure it with a piece of 1/2 inch angle iron. Each side of the iron should also be at least 4 inches wide with the entire piece at least 2 feet long. This will give some added strength and take care of any cracks in the wood itself. To install the iron you will need to drill several holes for the carriage bolts to be driven into. Use a drill and a metal drill bit and drill at least 4 to 5 holes on each side of the iron.
Step 4 – Install Angle Iron
With the joist back to its original position, place one section of the angle iron on the upper most section of the rafter just before the area where it is sagging or broken. Attach it to the beam with carriage bolts, but do not tighten completely.
Step 5 – Reposition Jack
Once the iron is attached to the beam you will need to work fast to make sure that it does not sag again as you reposition the jack. Remove the jack quickly and set the iron onto the entire beam. Place the jack back underneath the beam, but this time under the iron piece.
Step 6 – Finish Securing Iron
Drive the remaining carriage bolts into the 2 by 6 roof rafter and tighten them all up. Begin to lower the jack down a little at a time so that iron can take the weight of the rafter and load of the roof. If there are other rafters that need to be repaired, follow the same procedure for each of them.
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