Installing a chimney pot increases the height of the chimney stack above the ridge line of a roof. The removal of smoke from a chimney is most effective when unobstructed wind can blow across the top of chimney, so it is important to have a chimney at the highest point of the house. Chimney pots come in a variety of shapes and sizes that can also add a design element to your property. The installation procedure to effectively secure a chimney pot onto a chimney stack is fairly straightforward.
Brush off all dust and loose debris from the inside and outside of the chimney pot, using a hand brush. Measure the diameter of the top of the chimney pot.
Cut a circular piece of metal mesh to the diameter measurement using a metal cutter. Caulk a line of waterproof sealant around the inside of the chimney pot at the top, using a caulking gun. Bed the metal mesh into the sealant, and allow the sealant to dry.
Attach a masonry blade to a circular saw. Plane off any chimney tile that exceeds the height of the centre of the chimney. Brush off dust and debris from the chimney tile, using a hand brush.
Mix a batch of cement mortar according to the cement manufacturer's instructions. Use a cement trowel and load a 7.5 cm (3 inch) depth and width of mortar around the flue on top of the chimney stack.
Centre the chimney pot over the mortar bed and chimney flue. Apply even downwards pressure to the chimney pot to firmly bed the pot into the mortar. Position a spirit level across the top of the chimney pot to check that the pot is level on the stack.
Use the cement trowel to angle the mortar bed from the outside of the chimney pot base so the mortar tapers to allow rain to run off. Make sure the cement bed is 7.5 m (3 inches) deep around the perimeter of the chimney pot so the pot is secure. Repeat the procedure for any more chimney pots that need to be installed on top of chimney stacks on your property.
Install the chimney pot in dry conditions with low wind to avoid chimney pot movement before the cement sets.
Wear a long-sleeved shirt, protective gloves, a respirator and safety goggles to prevent injury from the chimney tile planing.