Please note that the rafter length calculator works both ways. If you picked the rise, all you need to do is input its value, put in the roof's run, and the calculator will return the rafter length in the bottom-most field. If you want to learn more about the way it's calculated, check out our roof pitch calculator. You can choose the rise of the roof (which is its height), or the roof pitch (which is the slope created by the rafter). Start by deciding what you want your calculations to be based on. In the field above the illustration, pick either 'rafter length' or 'truss count'. To start your calculations, you need to choose from the two options mentioned above.
You can use it either as a rafter length calculator, and get the dimensions of your trusses estimated or as a roof truss count calculator, which will also allow you to estimate the roof truss costs and even include the price of installation.
