How to Frame a Hip Roof Addition How to Frame a Hip Roof Addition
Although many modern roofs are framed using pre-fabricated trusses there is still a need for handmade roof addition framing. Hip roofs in particular need to be framed by hand because of the more complicated nature of them.
Learning how to frame a hip roof addition isn't actually that difficult as long as you have the right tools and materials available. While it is slightly more complicated to frame a hip roof than a gable roof this really shouldn't put you off at all. With enough planning you should have no problem framing a hip roof addition.
Step 1 - Measuring the Ridge Board
First you need to measure the length of the ridge board on your house. To work out the required length it's simply a matter of measuring the width of the building and taking this away from the length. For example if your building is 30 feet long and 20 feet wide then the ridge needs to be 10 feet long.
Step 2 - Cutting Rafters
Now you need to cut the length of all the common rafters, this is exactly the same process as if you were cutting rafters for a gable roof. Work out the length of these based on the building size and pitch of the roof. A seat cut will need to be made in the rafters which will allow the rafter to fit snugly on the top of the wall, this will create a good fit and a nice sturdy rafter.
Step 3 - Fixing the Common Rafters
The common rafters now need to be nailed into the ridge board at each side. Lift the ridge board and nail the common rafters on the other side of this so that the ridge is securely held in place.
Once all of the other common rafters are fitted the ridge will be firmly locked in place and unable to move.
Step 4 - Hip Rafters
Work out the length of the hip rafters, this will need to extend from the ridge down to the corner of the building. This needs to run at a 45 degree angle. You can look this up in tables or instead do some simple mathematics.
Step 5 - Straight Hip Rafters
It's essential that these hip rafters do not move while you are fitting the jack rafters. To ensure that this is the case use a piece of string to make sure that the hip rafters don't move out of the 45 degree angle.
Step 6 - Installing Jack Rafters
Work out the length of the jack rafters by looking through a rafter table on the Internet. These are then cut to size and installed in the same way as a common rafter. Ensure that the hip rafters don't move out of place while you are doing this. All 4 of the hip rafters need to be at perfect 45-degree angles for the roof to be finished properly.