How to Add a Cupola to a Metal Roof
- Determine your roof pitch. The pitch of a roof is calculated by the number of inches it rises vertically for every 12 inches it extends horizontally. Measure 12” out horizontally from the peak of your roof, then measure down until you meet the slope of the roof. This is your roof pitch. (E.g., if the vertical drop is 10”, your roof pitch is 10-12. If the vertical drop is 6”, your roof pitch is 6-12.) For our Sundance cupolas, we will cut out your roof pitch for you. If you have questions about how to determine your roof pitch, our cupola specialists are happy to assist you!
- Find and mark the center of your roof, then mark where your cupola will sit, measuring out from the center mark. (For example, if your cupola base is 24”, measure 12” on either side of the center line.)
- Prepare your roof. If you are adding a decorative cupola, there is minimal preparation. Simply cut and remove the section of ridge vent or cap where the cupola will sit. If you are adding a functional cupola to your metal roof, you will need to cut an opening into the roof itself. Cut a hole that is at least 6” smaller than the inside perimeter of the cupola base. (E.g., a 24” cupola would require an 18” hole.) Be sure not to cut any structural supports. Just cut the metal roofing itself, not the ridge or rafters.
- Secure the cupola base to the structural framing members (ridge, rafters) with non-ferrous screws or nails driven at an angle. Do not fasten the cupola to the roofing alone. (Note: for larger cupolas - over 36” - you may need to install additional wood supports inside the cupola base. This is also beneficial for buildings that experience high winds.)
- Install flashing around the cupola base to ensure a watertight fit and use caulk to seal the sides as well.
- Once the base is installed, you can finish assembling the cupola. Our cupolas come in three sections - base, midsection and roof - for quick and easy assembly. Simply place the midsection on top of the base and attach with 2” screws using the pre-drilled holes. Then place the roof on the midsection and fasten with screws, again using the pre-drilled holes.