Building A Cupola

What You'll Need
Hardwood (preferably cedar)
Marine plywood
Miter saw (can be hired)
Wood stain

A cupola is a box-like structure with a miniature roof that sits on top of a garage or house. They were originally constructed to give ventilation to grain stores and attic spaces. However, most modern buildings have adequate ventilation and only have cupolas for decoration.

Step 1 – Choose a Design

The easiest cupola for a do-it-yourselfer to construct is a cube-shaped frame with slats fitted at angles.

Step 2 – Make the Vents

To make the vents, take four cedar posts you intend to use as the edges of the cupola. On one corner of each post, cut slots at a predefined length apart from one another. The slots should be cut at 45 degrees. You can set your miter saw to ensure that the angle is are consistent. So when you have finished making the slots, each post should have eight slots, intersecting to make four upside down “V” shapes. The next thing to do is insert the slats into the slots, so that the structure is joined together loosely. When you are confident that you have the correct angles, secure the slats in place with nails.

Step 3 – Make the Roof

Next, use a square of marine-grade plywood for your roof. Cut four scalene triangles (each with a right angle), which will go back to back to form rafters. Use a carpenter’s square for this to ensure precision. Then make a tongue and groove roof for this part. Do not worry if it is not perfect. After all, no one will be able to see the exact details from the ground!

Step 4 – Securing Triangle Slopes to the Base

The secret to fixing the cupola to the roof is in making triangle slopes at the exact angle of the pitch. The best way to do this is to get two batons of wood that you have hanging around in your garage, and lay them either side of the roof ridge. Nail them together at the top where they meet, and you will have a pattern to follow. Using the nailed-together batons as a measure, cut out a pair of base pieces of wood for the cupola to stand on. Then join these together. If you picked this structure up, it would look like a square. However, if you looked at it from the side, you would just see the cut-out angle you have just measured.

Step 5 – Fixing the Cupola to the Roof

When you have attached all the component parts of the cupola together, now is the time to stain it with a wood stain. When it has completely dried, attach it to the roof ridge by screwing it in place. To be on the safe side, also use a silicone sealant to ensure that the cupola and the roof are still waterproof where they meet.