How to Measure For a Chimney Cap

I have always said the hardest part of installing a chimney cap is getting out the ladder and you have to do it twice. Once you get the energy to get the ladder out and get up on the roof the rest is simple. The first climb on the roof is to measure for the chimney cap. Remember to take a tape measure, paper and pencil with you! There's nothing like getting down and forgetting if it was the big line or little line you were looking at on the tape measure. Write it down while you're up there, then measure it again. Measure twice buy once! Below is a list of chimney caps and the measurements needed for them.

Single flue chimney with the clay tile raised from the crown is the most common. The best chimney cap will be an outside fit with 4 simple pressure screws. Measure the INSIDE of the flue tile length and width. Chimney caps are available in black galvanized, stainless steel and copper. Black Galvanized Stock sizes

Multi-Flue chimney cap is designed to cover several flues at one time. If the flue tiles are more than 6 inches apart you can use single flue chimney caps for each one. Using a multi-flue chimney cap tends to give your chimney a cleaner look with only one cap covering all the flues. Measuring for multiple flue chimney caps can be a little
more difficult especially if the flue tiles are offset. Using the diagram below you will need to measure the widest point for all 4 sides, sometimes the flues are not set square to each other.