Step-by-Step Construction for a Chimney Chase Top

Screw or nail the chase top shroud together. Many manufacturers will ship a shroud in flat pieces to a customer or retailer, requiring a basic parts assembly. Depending on the shroud's design, install screws or nails to attach the shroud covering to the supportive legs by using a screwdriver or hammer.

Nail or screw in 4-1.5-inch flashing spacers to the chimney's bare opening using a hammer or screwdriver. Each spacer should be near each chimney corner. The spacers provide a gap between the chase top flashing and the chimney's combustible length for preventing any fire hazards during wood-burning season.

Place the chase top flashing over the spacers. Nail or screw the flashing to the spacers and chimney length with a hammer or screwdriver.

Place the chase top shroud on the flashing. Connect three sheet metal screws to each leg on the shroud, using a screwdriver and securing the shroud to the chimney's assembly.

Begin a fire in the fireplace. Observe the chimney chase top assembly as the smoke exits the building. Verify that the smoke is not being impeded by the shroud.