The goal is to prevent conditioned air from escaping or unconditioned air from entering the thermal envelope.
Floor vent seal.
Inspect your floor vents.
If you live in a house with a crawl space there is a good chance the floor vents are not sealed.
If you do unscrew one of the floor vent covers and set it aside.
Next apply weather stripping around the underside of the vent cover.
Is there a gap between the metal duct and the floor.
You have an unsealed vent.
While it certainly is possible to abandon the under slab ducts and to put ducts in soffits or an attic this.
This will further improve efficiency and prevent energy losses.
Find floor registers at lowe s today.
To properly seal around air vents apply caulk or expanding foam between the ducting and the sheetrock.
Check to make sure you have a crawl space and that you have air vents coming up through the floor.
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