How to Frame a Roof for a Tree House

What You'll Need
Tape Measure

If you are building a tree house, you can frame a roof for it on your own. The roof will extend the life of the tree house and is just as important as the rest of the framing. A flat roof is the easiest to install and, when built correctly, is easy to maintain. Follow the simple steps below to frame your own tree house roof.

Step 1 - Understanding the Dimensions

Even though these are called flat roofs, they do have a slight pitch. A completely flat roof would not allow for proper drainage and runoff from rain and snow. A flat roof will have a pitch that is no higher than 1/4-inch of the rise. To find the pitch for the frame, you need to find the rise and run. You can find calculators online to help you find these exact numbers.

Step 2 - Finding the Square

In a perfect world, your tree house wall framing would create a perfect square. However, even professional contractors can't pull this off. Before you start framing with rafters, you need to find out just how square the tree house is. To do this, use a tape measure to measure from corner to corner. You may be surprised to see a few inches off between the walls. Write down the numbers you have; you can work around the measurements later.

Step 3 - Correcting the Square

You aren't actually going to rebuild the tree house frame in this step. Instead, you are going to compensate for how out of square the structure is. Find a corner that isn't square, and create braces to run at the top corner of the wall. 2x4-inch boards work well for this, and you will end up with a square to work with. Once you finish one corner, move on to the corner opposite of it and work on that one. The result should be a shape similar to an upside-down V.

Step 4 - Laying Out the Rafters

Choose the wall where you are going to start the rafters. From here, measure out to the center of the tree house.