How to stop draughts through evaporative cooling outlets

Sealing evaporative cooler outlets can reduce air leakage by 20%.

The ceiling outlets of ducted evaporative cooling systems can be a significant source of heat loss.

Heated air can escape from around the outside of the outlets, as well as through the louvres into the ductwork. Although the louvres of the evaporative cooling system can be closed off manually after each summer, they do not form a tight enough seal to stop heat loss in winter.

Sealing an evaporative cooling unit

Step 1: Getting started

There are commercially available covers that can be fitted over the ceiling outlet in winter to eliminate air leakage through the louvres.

Step 2: Fixing the problem

It is important to ensure that the covers you purchase are suitable for the type and size of your ceiling outlets. You may need to use a caulking compound around the outside of the ceiling outlet to create a nice tight seal.

If an appropriate sized cover can’t be found, there are DIY solutions such as covering them with a product like ‘Contact’. Also, fit a cover over your roof mounted evaporative cooler when it’s not being used.

Cover for evaporative cooling unit

More information

If you need to know how to seal up other areas around the house, this information is covered in the following guides: