How to measure your sofa
Two numbers, three if you have a sectional. It takes about a minute, and it is what matches you to the board that performs best on your sofa.
Before you pick up the tape
Take the cushions out first, and measure the bare seat base underneath them. Cushions overhang the frame by an inch or two on every side. The seat base is the surface the board actually rests on, so the seat base is the measurement that matches you to the right size.
About a minute with a tape measure
Three steps, two numbers
Nothing here needs a second person or anything more than a tape measure. Write both numbers down as you go.
Clear the seat
Take every seat cushion out and set them aside. You want to see the flat seat base, corner to corner. That seat base is what every number below refers to.
Measure arm to arm
Run the tape along the seat base from the inside face of one arm across to the inside face of the other. Keep it straight rather than following any curve in the frame. This is your inner width.
Measure front to back
From the front edge of the seat base straight back to where the backrest begins, square to the front edge rather than angled across a corner. Round both numbers down to the nearest half inch.
Seen from above, cushions out
What you are measuring
Inner width runs from the inside face of one armrest across to the inside face of the other. Not over the arms, not the outside of the sofa. You want the space your cushions actually sit in.
Seat depth runs from the front edge of the seat base straight back to where the backrest begins. Keep the tape square rather than angled, or you will read long.
Round to the nearest half inch, and round down on both numbers. A board that sits a little inside the space is exactly where you want it: fully on the seat base, spreading your weight evenly across the whole seat.
Worth checking twice
Where people go wrong
None of these take long to undo, and all of them are easier to catch now than after the box arrives.
Said plainly
When this is not the answer
The board solves one problem: a seat base that has gone soft underneath the cushions. That is what is wrong with most sagging sofas. Here are the cases where it is not.
A frame that has cracked or given way
If the sofa creaks under you, leans, or one corner has dropped, the problem is the structure rather than the seat base. A board laid across the seat will not straighten a frame.
Springs that have snapped rather than stretched
Webbing and springs that have slowly gone slack are exactly what this is for. Metal that has actually broken needs a repair, and the board would sit on top of the fault rather than take its place.
Cushions that are worn right through
The board gives your cushions a firm base to rest on. It does not put thickness back into foam that has collapsed. If the cushions themselves are thin and flat, you are looking at new cushions as well as a board.
A sofa bed
It helps with the sag, but it cannot fully cancel out the folding mechanism underneath. Go in expecting an improvement rather than a fix.
You like sinking into your sofa
This makes the seat firmer. That is the whole point of it, and it is the wrong buy for anyone who wants soft. We would rather say so here than have you send it back.
Not sure which one you are looking at? Take the cushions out, photograph the bare seat base, and send it to us. We will tell you straight whether the board will help, including when the answer is no.
Got your numbers?
Put them into the size finder and we will tell you exactly which board fits. Or send them to us and a person will check them for you.
The awkward cases
When your sofa is not a textbook sofa
My sofa has three seat cushions. Do I measure one of them?
No. Measure the whole seat base, arm to arm, in one go. One board covers the entire seat regardless of how many cushions sit on it. It is hinged, so it folds flat to ship and opens out across the full width.
My sofa has no arms. Where do I measure from?
From one end of the seat base to the other, where the cushions were sitting. The rule is the same on every piece: you are measuring the space the cushions occupy, not the outside of the furniture.
The seat base is springs and webbing, not a solid platform. Does that change anything?
No, and that is the usual case. Webbing, straps and springs are exactly what stretches out over time, which is the problem the board is there to solve. Measure the same way, arm to arm and front edge to backrest, and the board rests across it.
Should I round up or down?
Down, on both numbers, to the nearest half inch. The board does its best work sitting fully on the seat base with a little room at the edges, so rounding down is the side to err on.
What if I am between two ranges?
Take the smaller one. It sits fully inside the seat area, which is where you get firm, even support right across the seat, and the panel gaps can be closed up to bring a slightly narrow one in. If you would rather have someone confirm it, send us the numbers first.
Do I need the seat height or the back measurement as well?
No. Two numbers is all it takes: inner width and seat depth. A sectional needs a third, the length of the shorter arm of the L, measured exactly the same way.
My sectional is deeper at one end than the other.
That is normal, and it is why you measure the two sections separately. Take the long run and the chaise as if they were two different pieces of furniture. The size finder will tell you whether one set covers both or whether a pair sized to each section suits you better.
What if my measurement falls outside all the ranges?
Send us the numbers before you order. Give us the inner width, the seat depth and what the piece is, and we will tell you which board suits your seat, or tell you plainly if none of them do. We would rather answer that now than have you guess.
Can someone confirm my measurements before I order?
Yes, and it costs nothing. Send us the width, the depth and what the piece is, plus a photo of the bare seat base if you have one, and we will confirm the match. A size confirmed in advance is the simplest way to get the full benefit from day one.
What if the size I ordered is not the right match?
You have thirty days. Return shipping is at your cost, and the refund goes out as soon as it arrives back in good condition. Tell us your numbers and we will help you land on the right one instead.
Sit down without bracing yourself.
Find the size that fits your deck and give the cushions something solid to land on again.
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