How to Build a Wood Cupola

A wood cupola adds elegance and style to your home. Usually, these constructions are placed on rooftops of barns or garages. While this is still common, they are becoming a popular addition to home rooftops as well.

Most cupolas are built for ornamental decoration; however, they can also provide ventilation into attic spaces or serve as light sources. In some cases, a weather vane tops off a wood cupola. To build your own non-venting cupola, follow these directions.

Step 1 - Choose Your Wood

Before you begin building, you need to think about the design of your cupola and what kind of wood you will use to build it. Cedar or pressure-treated lumber are good choices because they are weather-resistant and rot-resistant. You could use hardwoods such as oak or cherry, but they cost more and don't have a traditional or country-style look.

Step 2 - Size it Correctly

If you make the cupola too small, it may look awkward on your rooftop. But, if you make it too big, it may overpower other architectural elements of your house. A good size for most applications would be about two-feet wide by two-feet deep. The height should be about three feet or slightly less, not including the weather vane or finial.

Step 3 - Build the Sill

The sill portion of your wood cupola sits on the roof itself.

Cut the Lumber

Cut the 8-foot lumber into four equal pieces, each about two-feet long. Cut two angled sections that will ride over the ridge of your roof. Two other straight pieces will run horizontal with the roof. These four pieces will form a box-shaped base for the cupola. Use a table saw or skill saw to make your cuts, following all proper safety precautions, including wearing goggles and gloves.

Wrap the Sill

Then, wrap this sill with roof flashing and tar it in place with your putty knife. Use tin snips to make your cuts.

Step 4 - Secure the Base

Using the L-brackets and screw gun, secure the base to the roof. Attach it with roof tar and stainless-steel screws, too. Then, cut a small piece of plywood to place on top of the box to make a flat base.

Step 5 - Build a Plywood Box

Next, build a plywood box with four pieces of plywood. The box will be two-feet wide, deep, and high. Cut a hole in each section of plywood to mount your louvered vent. Put this together with stainless steel screws and caulking. Use additional L-brackets to mount this box onto your sill base, and add brick mold if you desire.

Step 6 - Cut Curved Plywood Pieces

Cut out one curved piece from your plywood. Use it as a template to make three other identical cuts to make a pagoda look. The four sections will look like a portion of an octagon, and they should be about 18-inches high. Secure the curved pieces together with the flat L-brackets on the inside and silicon caulking on the outside.

Step 7 - Mount Your Weather Vane

Lastly, mount your weather vane on the top of the wood cupola with stainless-steel screws if you choose to have one.