RR-0408: The deKieffer Bypass

Effective Date

Construction practices have improved and the HVAC systems need to improve with them. The deKieffer Bypass relieves air pressure in rooms without compromising sound or light transmission.


This is an early prototype. It is simple and consists of a metal sleeve that eliminates air leakage to the wall cavity, and a door trim system that allows air to pass behind it.

The standard door frame is constructed and a sheet metal sleeve is installed above the door.

The trim package simply pulls the top trim and the corner blocks out 1/2” from the drywall.

This type of system provides better air relief, sound control and consistency that door undercuts or transfer grills.

The trim package allows for the pressure relief with increase in the perceived quality of the home

This picture clearly shows the air path behind the trim and the drywall detail. This system provides ~23 square inches of free air space.

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