Open the sofa bed and measure the interior width and length of the metal frame.
Replacing a sofa bed mattress can turn a lumpy, "bar-in-the-back" guest experience into a legitimately comfortable night's sleep. If your sleeper sofa’s frame is still in great shape but the mattress has sagged or the springs have started to poke through, a high-quality replacement is a cost-effective alternative to buying a whole new sofa.
Measure the height of the frame's side walls where the mattress sits. Standard sofa bed mattresses are 4 to 4.5 inches thick .
Products like the Sleeper Helper are folding boards that sit under the mattress to prevent sagging and block the feel of the support bars.
For foam, aim for a density of 1.8 lbs or higher. Lower densities (1.2–1.5 lbs) tend to bottom out and lose their shape quickly after being stored folded.
If a full replacement isn't in the budget, you can still improve the sleep quality:
Ensure the foam is CertiPUR-US® certified , meaning it’s made without harmful chemicals like formaldehyde or heavy metals.
