How to Measure Outdoor Bench Cushions (Benches, Porch Swings, Outdoor Swings & Built-In Seating)

Outdoor bench cushions may seem straightforward to measure, but “bench” can mean many different things—a standard garden bench, porch swing, built-in seating, poolside bench, or a bench against a wall. The key is to measure the bench frame, not just the old cushion. Accurate frame measurements help ensure a better fit, improved comfort, and a cushion that stays securely in place.

This guide explains how to measure outdoor bench cushions, including swings and built-in seating, while also covering cushion thickness, ties or Velcro ties, and finishing details such as piping.

Identify Your Bench Type

Before you begin measuring, determine which type of bench you have:

• Standard outdoor bench – freestanding seating

• Porch swing or outdoor swing – moving seating that may need extra support

• Built-in bench – often requires custom lengths, corners, or unusual shapes

• Bench against a wall – requires careful attention to depth and clearance

Measure the Bench Frame

Start with the frame, not the old cushion. Cushions can compress, lose their shape, and shrink slightly over time, so the frame provides the most reliable measurements.

1. Measure the Bench Width

Measure the usable seating area from left to right.

• If the bench has arms, measure between the inside edges of the arms.

• If there are no arms, measure from one edge of the usable seat deck to the other.

Bench Width = ____ inches

2. Measure the Bench Depth

Measure from the front edge of the seat deck to the back.

For benches with a backrest, measure to the backrest. For backless benches, measure to the rear edge of the seat deck.

Bench Depth = ____ inches

Tip for benches against walls: Leave a small amount of clearance if needed to prevent the cushion from rubbing or bunching against the wall.

3. Measure the Seat Deck Height

Measure from the ground to the top of the seat deck, without the cushion.

Seat Deck Height = ____ inches

This measurement helps you determine the finished seating height after adding the cushion.

Choose the Cushion Thickness

The ideal cushion thickness depends on the bench design, seat height, and how the bench will be used.

Consider:

• Whether the seat surface is solid or slatted

• The existing seat deck height

• Whether the bench is used for short periods or extended lounging

Common thickness options include:

• 2"–3" – slimmer profile and useful for taller benches

• 3"–4" – comfortable thickness for many outdoor benches

• 4"–6"+ – plusher, more cushioned feel for deeper seating and built-in banquettes

Check the Finished Seat Height

Before choosing the final thickness, make sure the cushion will create a comfortable overall seat height.

Finished Seat Height = Seat Deck Height + Cushion Thickness

For example:

• Seat deck height: 16"

• Cushion thickness: 3"

• Finished seat height: 19"

This simple calculation helps prevent a cushion from making the bench feel too high or too low.

Measuring Porch Swings and Outdoor Swings

Swings are measured much like standard benches, but they require a couple of additional checks.

1. Measure Between the Inside Arms

If your swing has arms, measure the inside-arm width to determine the actual usable cushion width.

2. Plan the Tie Placement

Because swings move, proper tie placement is especially important.

Common options include:

• Back-corner ties – the most important for keeping the cushion secure

• Additional back ties – useful for longer swings

Make sure the ties will not interfere with the chains, hangers, or other hardware.

Measure Built-In Bench Seating

Built-in benches often have unique dimensions, so they may require custom cushion shapes and sizes.

Measure:

• The full usable width of each bench section

• The seat depth

• Any obstacles such as walls, posts, trim, or corners

• Whether the bench tapers or angles

Common built-in configurations include:

• Straight bench

• L-shaped corner bench

• U-shaped banquette

• Angled or trapezoidal seating

Built-in tip: If the bench sits tightly against a wall, consider leaving a small amount of clearance to prevent the cushion from rubbing or bunching.

Choose Ties, Velcro Ties, or No Attachments

Not every bench cushion needs ties, but they can be especially helpful for:

• Porch and outdoor swings

• Smooth metal or aluminum seating surfaces

• High-traffic areas with children, pets, or frequent use

Common options include:

• Fabric ties – traditional and secure

• Velcro ties – convenient for removing the cushion and cleaning or storing it

• No attachments – suitable when the cushion fits securely in a built-in space or the surface naturally prevents movement

Choose Piping or No Piping

Piping is a finishing detail that can change the overall appearance of the cushion.

• Piping (corded edge): Creates a more traditional, tailored upholstered look

• No piping: Gives the cushion a cleaner, simpler, more modern appearance

Frame

• Bench width (inside arms, if applicable): ____"

• Bench depth (front to back): ____"

• Seat deck height: ____"

Cushion Choices

• Thickness: ____"

• Finished seat height: ____"

• Piping: Yes / No

• Attachments: Fabric ties / Velcro ties / None

• Use type: Bench / Swing / Built-in

When measuring outdoor bench cushions, start with the frame and consider how the cushion will be used. Swings may need additional ties, built-in benches may require custom shapes, and seat height should always be checked before choosing the cushion thickness.

Accurate measurements and the right finishing details will help create a cushion that fits properly, stays secure, and looks like it was made specifically for your bench.