Because the pipe gets hot building codes require 1 in.
How to seal an attic opening.
Sealing the attic hatch or door.
They also give you an easy area to add hook fasteners if needed.
Of clearance from class b flues 2 in.
If your hatch rests directly on the moldings add 2 1 2 inch wide stops around the opening.
The stops provide a wider surface for attaching the weatherstrip and a space to mount hook and eye fasteners.
Ever wonder how much your attic entrance costs you each month in your cooling and heating bills.
Small attic vents located below the roof peaks provide sufficient ventilation to let the moisture created by heat rising into the attic escape.
Install a gasket around attic access openings to air seal between the opening and the panel covering.
Insulate the cover with rigid foam that is glued in place or batt insulation that is mechanically fastened e g with wires and screws.
From masonry chimneys to any combustible material including insulation.
If the attic hatch rests on the molding you should add 2 1 2 inch stops around the entire opening.
The large vent opening allows the heat to rise and.
Finish up by sealing the access hatch with self sticking weather stripping.
The opening around a furnace or water heater flue is a major source of warm air into the attic photo 5.