What Happens to Foam Padding Under Carpet When Wet?

Foam padding under carpet is designed to cushion your steps, but it also absorbs water readily. When it gets wet, the foam swells and becomes heavy with moisture. It holds that water against the carpet backing and the subfloor beneath, which slows drying dramatically.

The longer the padding stays wet, the more damage it can cause. The water can seep into the wood subfloor, causing it to warp, rot, or grow mold. The carpet itself may also start to smell musty or develop stains that are hard to remove.

The longer the foam stays wet, the more time mold and bacteria have to grow. Mold can spread from the padding to the carpet and even into the air you breathe. That can cause health issues, especially for people with allergies or asthma.

Drying the padding quickly can help prevent permanent damage. You can start by blotting up excess water with towels and using fans to circulate air. If the padding is soaked through, you may need to remove it entirely to save the carpet and subfloor.

For minor spills, you can try to dry the padding yourself. Lift the carpet carefully and use towels to blot as much water as possible. Then set up fans to blow across the wet area and open windows to lower humidity.

For larger water damage, such as a flood or a burst pipe, the pros have equipment that can extract water and dry the materials faster. They may also use moisture meters to check if the padding and subfloor are dry enough. If the padding is beyond saving, they can remove it and replace it.

• Blot with clean towels to remove surface water
• Lift the carpet edge to expose the padding
• Use fans and dehumidifiers to speed drying
• Check for mold growth after a few days
• Call local water damage pros if the area is large