Under the cover, not on it
A flat seat photographs perfectly.
Seat foam replacement for transit, coach and school fleets in NYC. New cushions on the frames you already own, back under the covers you already have.
What flat actually means
Worn foam does not go soft. It goes hard.
A cushion does not wear away the way a cover does. The cells inside it collapse and stop springing back, so the seat loses height rather than losing material.
- It reads as hard rather than saggy. The cushion has lost height, so the rider sits closer to the pan than the seat was built to put them.
- The complaint arrives as backs and long shifts, not as an opinion about the upholstery.
- It shows first in the seats that get used most, under covers that still look perfectly serviceable.
What to specify
Density is what lasts. Firmness is what you feel.
They are two different properties and they move independently, which is how a seat can arrive firm and still be flat again long before it should be.
Density
What it lasts on
How much material is packed into a given volume. It is what decides how many times a cushion can be squashed flat and still come back up, and nothing else on the specification predicts that.
Firmness
What it feels like
The force needed to push the foam down. It sets whether the seat feels soft or supportive on the day it goes in, and it says nothing about how long it will go on feeling that way.
Foam suppliers put the order the same way: density first, for how long it lasts, then firmness, for how it feels. Buying on firmness alone is the usual way a fleet pays for the same problem twice.
Why the cover decides the job
The risk in foam work is the cover, not the foam.
New cushions come back at full height, so a cover that has spent years stretched over a collapsed one has to reach further than it has in a long time. Vinyl that has given up its plasticiser splits at the seams doing exactly that. So the cover is judged before any foam is ordered. Where it will still take the stretch it goes straight back on and nothing else changes; where it will not, restoring the finish first or recovering the seat outright is the honest answer, and either beats opening the same seat twice.
Before you order
What fleets ask about foam.
How do I know it is the foam and not the cover?
Cover problems you can see and foam problems you have to sit on. Press the middle of the cushion with the flat of your hand: sound foam pushes back and comes up again when you let go, and spent foam gives way and stays down. If the seat also feels hard through the base rather than soft, that is the cushion rather than the covering, and it is worth checking before you order anything, because a cover that has split or gone chalky is a different job with a different answer.
How much does seat foam replacement cost?
It is quoted against the vehicle rather than the seat. What moves the number is how many cushions are being changed, whether the seats have to come out to open them, and whether the covers that come off are going back on or being replaced at the same time. A fleet doing a run of vehicles is priced differently from one bus with a handful of tired seats, so a seat count and a vehicle count get you a real figure.
Do the seats have to come out of the vehicle?
Usually yes, because the cover has to come off the frame to get at the cushion, and that is not work you want done in an aisle. They go back on the same frames, in the rows they came out of. Fixed benches are the exception and are handled in place where the layout allows it. Either way the vehicle is scheduled around, not written off for the duration.
Can you do only the seats that have gone?
You can, and sometimes that is the right call, but it is worth knowing what it feels like afterwards. A new cushion sits taller and pushes back harder than the ones either side of it, so a part-done vehicle reads as uneven to anybody who moves down it. Operators who care about that usually do the whole vehicle at once and quote it as a bulk project; operators fixing a handful of the worst seats do not.
Whole vehicles and runs of vehicles are quoted as bulk projects. Where the covers are going as well, the job becomes school bus or fleet reupholstery instead.
Sit in it first
This is the one you cannot photograph.
Sit in the worst seat on the oldest vehicle, then tell us what you felt and how many seats are like it. That is enough to quote from. If the cover has gone as well, start with a repair or a restoration instead. Or call (347) 310-7483.
