Drywall foam is used to fill and seal awkward gaps, hollows, and cavities. It shoots liquid foam deep into cavities, creating a long-lasting seal, which insulates against heat, sound, and moisture.

Most foams are Polyurethane based (also known as PUR and PU) and is a highlight flexible compound which is essentially plastic based. It is vital that when using Polyurethane foams that you wear the correct safety gear including respiratory masks, hand and eye protection.

Its bonding structure allows for the foam to come out in a flexible format but dry hard, so that you can use it to fill awkward holes and deep gaps, and once filled, it remains stable. It’s often used in combination with lightweight fillers which work to fill small gaps and holes.

Step 1: Put on your safety gear.

Step 2: Clean the exterior of the hole so it’s free of dust and grease.

Step 3: Remove the top and apply the applicator straw to the top nozzle, being careful not to bend the straw.

Step 4: If the brand of filler you’re using indicates to do so, lightly spray the hole with water.

Step 5: Shake the can for 15 seconds.

Step 6: For optimal results, turn the can upside down and put pressure on the applicator nozzle until the foam begins to come out.

Step 7: Start at the lowest and furthest point of the hole and work upwards.

Step 8: Stop applying and shake at regular intervals during application. Remember that the foam is designed to expand so be careful not to overfill.

Step 9: The job is complete when the foam has expanded out and filled the entire hole. Allow the foam to sit and become solid. Depending on the foam you use, this can be anywhere between 5 minutes and 24 hours.

Step 10. Using a knife or saw, cut the overflow of foam so it sits flush to the wall.

Step 11. Using sandpaper, remove any excess foam.

Step 12: You can then use light wall filler to fill any small cosmetic holes that still exist.

Step 13: You may at this point want to attempt to recreate the wall style, whether that’s speckling the filler, or simply painting over to match the rest of the wall.

 

Foam fillers are often used to fill cavities where pipes have been removed, or surrounding external plastic pipes, between beams, frames and lintels, in concrete floors or timber construction. There are specifically designed fire foams for when you’re looking to offer fire-stopping properties. It is essential to always read the labels of products for correct application.

We sell both Everbuild and Siroflex cavity foam. Browse the full range.