by Refresh Home Improvements
Shows how to use spray foam as backing for drywall hole repair
Spray foam can act as a rigid backing for patching drywall holes that are too large for direct compound application. This technique works with either a basic spray foam can or a professional foam applicator.
Fill the hole with spray foam, ensuring it expands to cover the entire opening and adheres to the surrounding drywall edges. Use a standard spray foam can or a professional foam gun applicator for a cleaner result.
Allow the spray foam to cure completely until it is rigid and hard. Do not rush this step.
Using a utility knife, trim off any foam that protrudes proud of the wall surface. Also remove any loose drywall pieces around the edge.
Apply a thin fill coat of joint compound over the foam backer. Embed drywall tape into the wet compound, then apply another coat of compound on top.
Let each coat dry, then lightly sand. Apply one or two more thin coats of compound, sanding between each coat, until the surface is flush with the surrounding wall.