A waterproof cast, sometimes called a swim cast, is a fiberglass cast with a special waterproof cast liner or padding underneath. The outer layer is still a standard fiberglass cast, but the inner liner does not absorb water the way cotton padding does. This allows many patients, with their doctor's approval, to shower with a cast or even swim with a cast while the bone heals.
Guide prepared by the clinical supply team at OrthoTape — waterproof casting specialists since 2005.
In this guide, we explain how waterproof casts work, the different waterproof cast materials (including OrthoH2O, AquaCast, and Delta Dry), and how to care for a waterproof cast safely. While we offer all three systems, our primary recommendation for most families is OrthoH2O because of its simple one-piece design and patient comfort.
What Is a Waterproof Cast?
A traditional cast has two layers:
- A soft inner layer (usually cotton padding) next to the skin.
- A hard outer layer (usually fiberglass cast tape) that provides support and protection.
In a waterproof cast, the hard outer fiberglass layer stays the same, but the inner layer is changed to a synthetic waterproof liner. This liner does not absorb water like cotton. Instead, it allows water to flow through and drain out of the cast, so the skin can be rinsed and the cast can dry properly.
Waterproof Cast vs. Waterproof Cast Cover
Online, the term "waterproof cast" is often used for three very different things:
- Waterproof cast liners and padding – These are materials used inside a fiberglass cast. They are applied by a medical professional and become part of the cast itself. This is what OrthoTape sells in our waterproof cast collection.
- 3D lattice cast alternatives – Custom brace or cast alternatives with open, waterproof structures. These are a different technology from traditional fiberglass casts and may be available only through specific providers using specialized equipment.
- Waterproof cast covers – Plastic sleeves worn over a cast for showering or bathing. They do not make the cast itself waterproof; they simply try to keep water off a regular cast.
OrthoTape focuses on the first group: waterproof cast liners and waterproof cast padding that are used by clinics and hospitals to build a true waterproof fiberglass cast. We do not manufacture or sell disposable plastic cast covers.
Types of Waterproof Cast Materials We Offer
OrthoTape carries three main waterproof casting systems. All of them work with fiberglass cast tape, but OrthoH2O is our preferred, streamlined option for most families and clinics.
One-piece waterproof cast stockinette that slips over the limb and is finished with fiberglass cast tape to make a waterproof arm or leg cast.
Two-piece system with waterproof stockinette and padding for clinics that prefer a wrap-and-pad technique.
Pillow-type waterproof cast padding in roll form, available in kits for short arm, long arm, and short leg casts.
1. OrthoH2O Waterproof Cast Stockinette
OrthoH2O (formerly OrthoNEAL) is a thick, fishnet-shaped cylindrical waterproof cast stockinette. It is hypoallergenic and made from advanced synthetic fibers designed to wick water away from the skin quickly, drain water out of both ends of the cast, and reduce odor and moisture build-up compared to traditional padding.
OrthoH2O is a one-piece slip-on design that goes directly on the limb under fiberglass cast tape. When applied correctly, it creates a comfortable waterproof arm cast or waterproof leg cast that many patients can use for showering and swimming, with their provider's approval.
Shop OrthoH2O: OrthoH2O – Waterproof Cast.
2. AquaCast Waterproof Cast Padding
AquaCast is the original waterproof cast padding that uses a soft, pillow-type synthetic material in roll form, originally developed by the makers of Gore-Tex. AquaCast padding is wrapped around the limb and covered with fiberglass cast tape to create a waterproof cast. Available in dedicated kits (short arm, long arm, short leg) that include waterproof padding, saw-stop strip, and fiberglass casting tape.
Shop AquaCast: AquaCast – Waterproof Cast.
3. Delta Dry Waterproof Cast Padding
Delta Dry is a two-piece waterproof cast system with synthetic stockinette and padding. The liner feels similar to nylon and allows water to pass through and drain while still providing soft support under the fiberglass cast. Popular in clinics that want a familiar wrap-and-pad system but need the benefits of a waterproof cast.
Shop Delta Dry: Delta Dry – Waterproof Cast.
Can You Swim With a Waterproof Cast?
With a properly applied waterproof cast liner, many patients are allowed to swim in clean, treated pool water. Major pediatric orthopedic centers note that waterproof casts can be submerged in water but may not be appropriate for all fractures or all patients. Decisions about swimming should always be made by your treating provider.
- Prefer swimming in clean, chlorinated pool water rather than lakes, rivers, or the ocean.
- Avoid sand and muddy water that can get trapped inside the cast.
- Rinse the cast well with clean water after swimming.
How to Dry a Waterproof Cast
After showering or swimming with a waterproof cast:
- Rinse the cast with clean water to flush out soap, chlorine, or debris.
- Hold the cast so water can drain from both ends.
- Pat the outside of the cast dry with a towel.
- Allow air to circulate around the cast until it feels dry.
- If recommended by your provider, you may use a blow dryer on a cool or low setting to help speed up drying. Do not use high heat.
Is a Waterproof Cast Right for Every Patient?
Waterproof casts are not right for every injury or every patient. Some fractures, surgical incisions, or skin conditions may require a traditional cast and strict protection from water. Always ask your orthopedic provider whether a waterproof cast is safe for your specific fracture, when you are allowed to shower or swim, and how to monitor your skin for redness, rash, or odor.
How to Ask Your Doctor for a Waterproof Cast
Many clinics do not stock waterproof cast liners. A simple option is to order a waterproof cast kit from OrthoTape and bring it to your appointment:
- Call ahead to confirm your provider is comfortable applying a waterproof liner under fiberglass.
- Order the correct size kit (short arm, long arm, short leg, etc.) from orthotape.com/collections/waterproof-cast.
- Bring the unopened kit to your visit.
- Ask for written instructions about swimming, bathing, and drying the cast.
Shop Waterproof Cast Products
OrthoTape carries all three major waterproof casting systems plus fiberglass casting tape in all widths and complete cast kits.
- All Waterproof Cast Products — OrthoH2O, AquaCast, Delta Dry
- Fiberglass Casting Tape — all widths and colors
- Cast Care Instructions — how to keep your cast safe and comfortable
Frequently Asked Questions: Waterproof Casts
What is a waterproof cast?
A waterproof cast is a fiberglass cast with a special synthetic waterproof liner or padding underneath instead of traditional cotton padding. The liner does not absorb water, allowing water to flow through and drain out of the cast. This allows patients, with their doctor's approval, to shower or swim while the bone heals.
What is the difference between OrthoH2O, AquaCast, and Delta Dry?
OrthoH2O is a one-piece slip-on waterproof cast stockinette made from Aerosliver yarn with antimicrobial silver ions and Quick-Wick Technology. AquaCast is a pillow-type waterproof cast padding in roll form, originally developed by the makers of Gore-Tex. Delta Dry is a two-piece system with synthetic stockinette and padding. OrthoTape recommends OrthoH2O for most families due to its simple one-piece design and patient comfort.
Can you swim with a waterproof cast?
With a properly applied waterproof cast liner, many patients are allowed to swim in clean, treated pool water with their doctor's approval. Avoid lakes, rivers, the ocean, and sandy water. Always rinse the cast well with clean water after swimming and follow your provider's specific instructions.
Can you shower with a waterproof cast?
Yes, most patients with a properly applied waterproof cast liner can shower normally. The synthetic liner wicks water away from the skin and drains out of the cast. After showering, rinse the cast with clean water, pat the outside dry with a towel, and allow air to circulate until the cast is dry. A blow dryer on a cool or low setting can help speed drying — do not use high heat.
How do you dry a waterproof cast after swimming or showering?
Rinse the cast with clean water to flush out soap, chlorine, or debris. Hold the cast so water can drain from both ends. Pat the outside dry with a towel and allow air to circulate. If recommended by your provider, use a blow dryer on a cool or low setting. Never use high heat. The waterproof liner dries significantly faster than cotton padding.
Is a waterproof cast right for every patient?
No. Waterproof casts are not appropriate for every injury or patient. Some fractures, surgical incisions, or skin conditions require a traditional cast and strict protection from water. Always ask your orthopedic provider whether a waterproof cast is safe for your specific situation.
How do I ask my doctor for a waterproof cast?
Many clinics do not stock waterproof cast liners. Order a waterproof cast kit from OrthoTape and bring it to your appointment. Call ahead to confirm your provider is comfortable applying a waterproof liner, order the correct size kit, bring the unopened kit to your visit, and ask for written instructions about swimming, bathing, and drying the cast.
What is the difference between a waterproof cast and a waterproof cast cover?
A waterproof cast uses a synthetic liner applied inside the fiberglass cast by a medical professional — it becomes part of the cast itself and allows true water exposure. A waterproof cast cover is a plastic sleeve worn over a regular cast for showering; it does not make the cast waterproof. OrthoTape sells waterproof cast liners and kits, not plastic cast covers.
