Short answer
Tumble dry low or line dry, as the care label says. Casper warns that heat drying can cause delamination and shrinkage of a TPU protector. Make sure it's completely dry, including the skirt and seams, before it goes back on the bed; a damp protector traps moisture against the mattress.
Key terms used on this page
- Delamination:
- When a protector's waterproof film separates from its fabric, showing as bubbles, peeling or flakes. Casper warns heat drying can cause it.
- TPU membrane:
- A thin thermoplastic polyurethane film laminated to a protector's face fabric to stop liquid. Casper lists 'Polyester with Thermoplastic Polyurethane' for its waterproof protector's top.
- Care label:
- The care instructions sewn into a mattress, topper or cover. Tempur UK notes that 'A label stitched inside the cover will give you specific care instructions for the item you have purchased.' A care label outranks general web guidance.
Most protectors are ruined in the dryer, not the washer.
General information about mattress care, not medical advice. For allergy or asthma questions, talk with your doctor.
Low heat or line dry
Casper's instructions: "machine wash on cold and tumble dry low. It will be tempting to wash and dry on hot — resist this urge! Heat drying could cause delamination and shrinkage." They add, "You may also opt to air dry."
Signs of heat damage
Delamination shows up as bubbles, peeling or flakes of film. Once the membrane separates, it no longer reliably stops liquid. See when to replace a mattress protector.
Fully dry before it goes back on
The EPA's mold guidance is to dry wet items within 24 to 48 hours. A protector that goes back on damp traps moisture against the mattress: see moisture and mildew under a protector.
Sleep Sanitation's view
This section is our view. Sleep Sanitation serves Omaha, Lincoln and surrounding towns. Every visit includes dry vapor steam, HEPA vacuuming, UV-C light treatment, the built-in bed mite sensor on our JIGOO UV-C mattress vacuum and a moisture check before we leave. We take your protector off at the start of the visit, so you don't need to strip it first; wash it yourself per its care label while we work or afterward. The first mattress is $249. Call or text (402) 512-5658, or email info@sleepsanitation.com. Office hours are Monday to Friday, 9 to 6, and we return calls and texts on weekends.
Changelog
- 15 October 2026: First published. Sources accessed on this date.
Sources
- Waterproof Mattress Protector: Materials & Care · Casper
- A Brief Guide to Mold, Moisture and Your Home · US Environmental Protection Agency
Last reviewed October 15, 2026. Manufacturer specifications and care instructions change; check the current version for your exact model. This page is general information, not medical advice. How we source and check pages: editorial standards.