Drafty Window Weight Pockets

Looking for contractor to reconfigure drafty old windows by replacing the rope and weight system and insulating the channels where the weights were. Is this something you can do?

Blower door test on an 18th century mill house.

The short answer is no, we do not fill weight pockets.

The way a house manages air flow changes from house to house and has everything to do with the way it was built, what period, and what part of the envelope is actually leaking. 


The weight pocket is just one part of the building envelope where air can be coming from lots of places. Filling the weight pocket doesn’t necessarily stop the air at the source, but rather diverts to another vulnerability in your interior envelope, like baseboards, trim, cracks in plaster, etc. 


So it doesn’t necessarily pay to replace a weight and pull system for building efficiency. Plus the weight and pulley is the best window operating system ever made.


An energy audit with a blower door test will expose the areas where and how air is coming in. The solutions depend on the source of the air; it could be repairing the exterior trim and siding, insulation/air sealing, sealing penetrations through the building, storm windows or any combination of work. We balance the materials and methods on what effect they will have on the building, its health, longevity, effectiveness, and of course, budget.


National Grid has an energy efficiency program with financial incentives and we have worked with an Auditor that can get you into some of their options. The program does blower door tests, but it does not look at your windows, look at the building holistically, or consider the impact as much. 


So that is why we don’t fill weight pockets.