Garden Bench Cushion Sizes: A UK Guide in cm

Quick answer: Most UK garden benches are about 120 cm long for two people, 150 cm for three and 180 cm for four. A "4 ft" bench is roughly 122 cm and a "5 ft" bench roughly 152 cm. Measure the seat between the arms, not the whole bench, and order your garden bench cushion to that size.

A bench sold as "5 ft" can measure 172 cm from end to end, and the seat between the arms on a bench that size can be nearly 20 cm shorter. That gap is why so many bench cushions slide about or bunch up at one end. This guide gives the common sizes in cm and shows you how to measure your own bench properly.

What size are UK garden benches?

Most UK garden benches fall into three lengths: about 120 cm, 150 cm and 180 cm. Retailers often still name them in feet, so it helps to know the conversions.

Under the Weights and Measures Act 1985, a yard is exactly 0.9144 metres and a foot is a third of a yard. That makes one foot 30.48 cm. So a 4 ft bench is about 122 cm, a 5 ft bench about 152 cm and a 6 ft bench about 183 cm.

Treat these as starting points only. In the UK listings we checked, a 4 ft two-seater measured 122 cm overall, while one "5 ft" bench measured 172 cm and a three-seater measured 170 cm. Names vary, so a tape measure beats a label every time.

How do you measure a garden bench for a cushion?

Measure the seat between the arms, in centimetres, and round to the nearest half centimetre. Ignore the old cushion if you have one, because cushions shrink and lose their shape over time.

Seat depth matters as much as length. Bench seats are often somewhere around 40 to 50 cm deep; one 150 cm three-seater we checked had a 48 cm seat. Listings also give an overall depth of 60 to 75 cm, but that includes the sloping back and legs, so ignore it.

1. Measure the width between the arms at the front of the seat.
2. Measure the width again at the back, next to the backrest. Some benches taper, so the two figures can differ.
3. Measure the depth from the front edge to where the back slats meet the seat.
4. Note where the back uprights and any centre legs sit. You will need this for the ties.
5. Check the arm shape. Curved or notched arms may need a template.

Our step-by-step guide to measuring cushions in cm covers trapezoid and curved shapes in more detail. Say your bench is 152 cm long overall, with arms 8 cm wide at each end. Your seat is then about 136 cm, and that is the number we need.

Seat pad or seat-and-back cushion, and how thick?

A seat pad covers only the seat, and suits most benches. A seat-and-back cushion adds a second piece that rests against the backrest.

A seat pad is quick to bring in when rain is forecast. Add a back cushion if your bench has hard, upright slats and you like to sit for a long time. Measure it from the seat to the top rail, and consider super soft foam, which is lovely to lean on but too soft for seats.

For thickness, 7.5 cm to 10 cm suits most garden benches. The benches we checked sat 42 to 46 cm off the ground, and a cushion adds its full thickness to that. On a tall bench, stay nearer 7.5 cm.

Our standard thicknesses run from 76 mm to 127 mm (3 to 5 in), and the builder goes up to 203 mm. Thinner pads are possible on request.

Where should the ties go on a bench cushion?

Ties should sit where they can wrap around something solid, usually the back uprights or a back slat. That stops the cushion sliding forwards when you sit down.

Tell us where your uprights are, measured from one end of the seat, and we place the ties to loop around them. Ties come in matching fabric as standard, with Velcro on request.

We don't add rubber or non-slip backing. It would stop the cover being machine washable and would void the warranty.

Which fabric and foam suit a bench left out in the rain?

For a bench that stays out, use outdoor fabric with quick-drain open-cell foam. This foam has an open structure, so rainwater runs straight through rather than soaking in.

British rain is the main test. Met Office averages for 1991 to 2020 show the UK gets about 1,163 mm of rain a year, falling on around 159 days. Even drier Heathrow sees rain on about 112 days.

Sunbrella says its fabrics "range from water-resistant to waterproof." Most Sunbrella is water-resistant, so water beads up and runs off, but a long downpour will get through. Its waterproof and marine ranges keep water out completely. Browse our Sunbrella cushions or read our guide to waterproof garden cushions to see which suits your garden.

High density foam is the all-purpose choice for a covered porch or a bench under a pergola. Foam for UK orders is made and cut in the UK.

Teak, iroko or metal: does the bench change the cushion?

Yes, a little. Hardwood benches can stay out all year, while metal benches need a bit more thought about drainage and rust.

The RHS says teak and iroko are durable because they contain high levels of natural oils, so they can stay outside over winter. It advises washing them once a year and keeping their feet off wet ground. Timber merchant Timbersource notes that iroko is often used as a cheaper alternative to teak.

A wet cushion holds moisture against the wood, so stand it on edge after rain. On metal benches, the RHS suggests checking for rust and repainting every two to three years. Rust from chipped paint can mark a pale cover, so darker fabrics are safer on metal.

How should you store bench cushions?

Store cushions clean, dry and with air around them. A shed, garage or cushion box works well, as long as it isn't damp.

Clean them first. Sunbrella says its fabrics do not promote mildew, but mildew may grow on dirt left on the fabric. Let them air dry fully, and avoid sealing them in plastic bags, which trap moisture.

If your bench stays out over winter, the RHS recommends heavy-duty waterproof covers for the furniture. After a few seasons, you can order covers only and keep your existing foam.

How do you order made to measure bench cushions?

Order online with your seat size in cm, your thickness and where the ties should go.

Start with our bench cushions, or go straight to a custom Sunbrella bench cushion. We cut every cushion within 6 mm (maximum ±2.5 cm) of your measurements and remake it free if we miss. If you're unsure on colour, order fabric swatches and see them in your garden's own light.

Standard shapes take 2 to 3 weeks to make, and template shapes take 5 to 6 weeks. UK delivery is free, with import duty and VAT already paid, so there's nothing to pay on arrival.

Frequently asked questions

What size is a 2 seater bench cushion?

Most two-seater benches are about 120 cm long overall, which is roughly 4 ft. The seat between the arms is shorter, because the arms take up part of that length. Measure your own bench between the arms and order to that size.

What size is a 3 seater bench cushion?

Three-seater benches are usually about 150 cm long overall, close to 5 ft. Some measure up to 170 cm. Always measure the seat between the arms, as that is the size the cushion needs to be.

Can I leave a garden bench cushion outside in the rain?

Only if it has outdoor fabric and quick-drain open-cell foam. Water then runs through instead of soaking in. Even so, the cushion lasts longer if you stand it on edge after rain and store it over winter.

How thick should a garden bench cushion be?

For most benches, 7.5 to 10 cm is comfortable. Choose thinner on a tall bench so your feet still reach the ground, and thicker on a low or deep one.

Do bench cushions need ties?

Ties stop the cushion sliding forwards when you sit down. They work best wrapped around the back uprights or a slat, so tell us where these sit when you order.

Sources

• Met Office: UK climate averages, 1991 to 2020
• Met Office: Heathrow climate averages
• RHS: Maintaining garden seats and tables
• legislation.gov.uk: Weights and Measures Act 1985, Schedule 1
• Sunbrella: Is Sunbrella fabric water resistant?
• Sunbrella: How to clean Sunbrella upholstery
• Timbersource: West African iroko timber