PU coating — polyurethane coating — is a thin layer of polyurethane applied to the surface of a base fabric, usually polyester. The coating bonds to the fabric during manufacturing and acts as a protective film, making the material water-resistant, more resistant to abrasion, and less prone to mould and mildew growth.
It's one of the most common treatments used in outdoor furniture fabric, workwear, tents, and bags. In the context of bean bags, it's what separates a fabric that can handle an Australian outdoor environment from one that will deteriorate within a season.
What PU coating actually does
Untreated polyester is naturally somewhat water-resistant — the fibres don't absorb moisture readily — but it's not waterproof, and it won't hold up under prolonged UV exposure or regular contact with dirt, body oils, and spills without some degradation over time.
PU coating addresses this by adding a continuous film over the fabric surface. The practical effects:
- Water resistance — water beads on the surface rather than soaking through. The coating seals the small gaps between fibres that would otherwise allow moisture ingress
- Abrasion resistance — the polyurethane layer takes the wear instead of the base fabric fibres, extending the usable life of the material
- Mould and mildew resistance — moisture that can't penetrate the fabric can't create the damp conditions where mould spores establish. This matters significantly for outdoor furniture left in humid conditions
- UV resistance — the coating provides a degree of UV protection that slows fabric degradation and colour fading from sun exposure
- Stain resistance — spills and surface contamination are easier to wipe off a coated fabric than an uncoated one
The coating is typically applied to one side of the fabric — the inner face — so the exterior retains the texture of the base material. The result feels like fabric, not plastic.
PU coating vs waterproof
PU-coated fabric is water-resistant, not fully waterproof. The distinction matters. A water-resistant fabric repels water under normal conditions — rain, splashing, surface moisture — but will allow water to penetrate under sustained pressure or prolonged exposure. A truly waterproof fabric (like those used in drysuits or pool floats) requires sealed seams and a more complete barrier construction.
For outdoor bean bags used on a patio or deck, water-resistant is sufficient. For bean bags designed for in-water or poolside use, we use a different construction entirely — Olefin fabric with quick-drain panels and wetsuit-grade zippers. See our pool bean bags for that category.
For a broader explanation of the difference, see our post on waterproof vs water-resistant fabric.
PU coating vs other outdoor fabric treatments
PU coating is one of several approaches used in outdoor furniture fabric. The main alternatives relevant to bean bags:
- Olefin (solution-dyed polypropylene) — the fabric itself is inherently UV-stable and moisture-resistant because the colour is embedded in the fibre during production rather than applied to the surface. No surface coating required. This is what we use in our premium outdoor range. More expensive than PU-coated polyester but more durable under sustained UV and moisture exposure. See our Olefin fabric guide for a full comparison
- Solution-dyed acrylic — used in high-end outdoor upholstery like Sunbrella. Extremely UV-stable. See our Olefin vs Sunbrella comparison
- DWR (Durable Water Repellent) — a surface treatment applied to finished fabric, typically on outdoor clothing. Less durable than PU coating and requires reapplication over time
PU-coated polyester occupies the mid-range of the outdoor fabric spectrum — more protective than untreated fabric, more affordable than Olefin, and well-suited to the majority of outdoor furniture applications in Australian conditions.
Which bean bags in our range use PU-coated fabric
Our 1680D polyester range uses PU coating as a standard feature. 1680D refers to the denier count of the polyester — a measure of fabric weight and density. 1680D is a heavy-duty specification used in luggage and tactical gear as well as outdoor furniture.
Products in this range include:
- Big Boppa — our most popular outdoor/indoor adult bean bag. 1680D polyester with PU coating, water-repellent, antimicrobial-treated, non-flammable
- Cayman — a double lounger built for two. Same 1680D PU-coated construction with a breathable finish that doesn't stick to skin in warm weather
- Merlin — high-back ergonomic design, 1680D polyester, suited to both indoor and outdoor use
- Bermuda — triangular lounger in heavy-duty outdoor polyester
- Big Bob — armchair-style bean bag in PU-coated fabric
- Media Lounge — lightweight, water-resistant, widely used for events and commercial setups
- Portofino — our largest oversized lounger, 140 × 80 × 80cm
All products in this range are suitable for outdoor use on covered patios and decks. They're not designed for prolonged immersion — that's what the pool range is for.
For a full comparison of all fabric types we use, see our bean bag fabrics and materials guide.
How PU coating performs over time
PU coating is durable but not permanent. A few things affect its longevity:
- UV exposure — prolonged direct sun accelerates coating degradation. Products left in full sun year-round will show wear faster than those in shaded or partially covered positions. This is one reason Olefin outperforms PU-coated polyester in very high UV environments
- Cleaning products — harsh solvents, bleach at high concentrations, and acetone can damage or strip the coating. Use mild soap and water for routine cleaning
- Physical abrasion — the coating on a bean bag used daily on a rough concrete surface will wear faster than one on a smooth deck or indoor floor
- Moisture trapped over time — if a PU-coated bean bag is left wet in a confined space for extended periods, the coating can eventually degrade and become tacky or delaminate. Allow covers to dry fully between wet periods
For practical guidance on keeping outdoor bean bags in good condition, see our post on protecting outdoor furniture from weather and our guide to preventing mould on outdoor bean bags.
Caring for PU-coated fabric
- Wipe down with a damp cloth and mild soap for routine cleaning
- For heavier soiling, remove the cover and hand wash or hose off
- Air dry thoroughly — do not tumble dry
- Avoid harsh cleaning products: no acetone, concentrated bleach, or solvent-based cleaners
- Store covered or indoors during extended periods of non-use if possible
- After contact with saltwater or chlorinated water, rinse with fresh water and allow to dry
For questions about the fabric specifications on any specific product, contact us and we can provide the full technical detail.
Frequently asked questions
Is PU coating safe?
Yes. Polyurethane coating as used in furniture fabric is non-toxic and safe for normal use. It doesn't off-gas harmful chemicals under normal conditions and is widely used in furniture, clothing, and medical applications.
Does PU coating make fabric fully waterproof?
No — water-resistant, not waterproof. It repels water under normal conditions but is not designed for submersion or sustained water pressure. For pool use, see our pool bean bag range which uses a different construction.
How does PU-coated polyester compare to Olefin?
Olefin is generally more UV-stable and more durable in harsh outdoor environments because the UV and colour resistance is built into the fibre rather than applied as a surface treatment. PU-coated 1680D polyester is more affordable and performs well in the majority of outdoor conditions. See our outdoor bean bag materials guide for a direct comparison.
Can I re-apply PU coating if it degrades?
There are aftermarket PU coating sprays available, but the results are variable and generally less effective than the original factory application. If a cover has significantly degraded, replacing the cover is usually a better outcome than attempting to re-coat it.
