Pergola Design with Curved Cedar Rafters

The Curved RAFTERS

I start by making a pattern for the curved shape of the rafters.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Cutting the pattern blank for the rafters

The pattern will be cut from thin plywood. I lay out a grid with tape measure, pencil, and straight edge.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Marking a grid on the rafter blank

Then I mark points where the curve intersects the grid.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Marking the points for the rafter pattern curves

I tap in a nail at these points then bend a thin strip of metal across them to form the upper and lower curve of the rafter.

Drawing Curves

Construction of a cedar pergola designed with curved rafters and curved corner braces
Flexing a metal strip against the nails to draw a curve

I used a strip of linoleum edge metal for this.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Lower curve drawing

I trace the curve on the plywood with a sharpie.
On the plans I also show the radius values for the two curves that make up the shape of the rafter. The curves could also be struck with a long straight piece of trim like a compass.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Rough some meat off the pattern for the next step

Over sawhorses I rough off a piece of the pattern to make the next step easier.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Small jigsaw rips through the thin plywood

Then cut the upper profile of the pattern with a jigsaw. Then use a belt sander to smooth and shape.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Belt sander is very fast at smoothing the curves

I reposition the pattern to cut the other curve.

Construction of a cedar pergola designed with curved rafters and curved corner braces
Nice!!

The location of the beam is also marked on the pattern then this birds mouth is cut.

Construction of a cedar pergola designed with curved rafters and curved corner braces
The birds mouth is also cut in the pattern

We had our sawyer mill boards just over 12″ wide for these rafters. Alternatively, thinner boards could be glued up to get the width required but, it’s a lot easier to just have them cut to what you need.

Completed Rafter Pattern

Construction of a cedar pergola designed with curved rafters and curved corner braces
The pattern is done! Yess!!!
Shopping Cart
Scroll to Top