Often thought of this but have read here and elsewhere that it just moves the problem by causing inefficient pressure build up.
Debunking the Closed-Vent Myth and How to Really Improve Air Flow
Closing air vents is a popular strategy for adjusting air flow in the home, but it's not necessarily a good one. The closed-vent myth has nothing to do with improving air flow in your home.
Could work for cold environments, but for keeping factories cool, some buildings use seawater to save money.
Often thought of this but have read here and elsewhere that it just moves the problem by causing inefficient pressure build up.