Check whether the cover comes off before anything else. Removable covers go in the washing machine on a cold gentle cycle and line-dry. Fixed covers get dealt with differently: vacuum first, blot liquid spills with clear dish soap and warm water, lift odours with baking soda, and let everything dry completely before anyone sits on it. Most damage to foam furniture comes from the drying stage, not the cleaning.
Start with the cover
Everything downstream depends on this answer, so find it first. Look along the underside and the back panels for a zipper track. On modular pieces the zipper often runs across the middle of the base rather than down a side seam, which is deliberate: hardware on the base stays off floors and out of reach, and the tension spreads evenly when the foam pushes back out.
If each piece unzips fully, you have the easier version of this job. If the cover is stitched on or only partially opens, skip ahead to spot cleaning and adjust expectations accordingly.
The weekly pass
Crumbs, hair and grit work into seams and stay there, where they slowly abrade the stitching every time someone sits. A vacuum with a brush attachment once a week does more for the lifespan of the fabric than any cleaning product.
Run the brush along every seam line and around zipper channels. On double-seat modules the gap down the middle collects a surprising amount. This is also what keeps floor models in a showroom looking current, if you are maintaining stock rather than a single piece in a playroom.
Machine washing the cover
Assuming the cover comes off:
- Cold water, gentle cycle. Warm water is what causes shrink and warping, and it also accelerates colour loss on printed panels.
- Skip the bleach. It degrades fibres and leaves residue on a surface that ends up against a child's skin. Enzyme-based stain removers work without it.
- Close the zipper before washing. An open track catches on other items and can bend out of shape.
- Line-dry rather than tumble. Dryer heat is rough on the firm printed fabric used for themed pieces and is the most common cause of a cover coming back slightly too small for its foam.
Washing the cover separately from other laundry is worth it. Dyes from jeans and dark towels transfer, and the result is a colour shift you cannot undo.
When the cover will not come off
Fixed upholstery is manageable, it just takes longer and demands more patience with drying. Work through these in order:
Blot, do not rub
Rubbing drives liquid deeper into the cell structure and spreads the stain outward. Press down with a cloth, lift, and repeat with a clean section. Slow, and it works better than scrubbing.
Clear dish soap and warm water
A few drops of dye-free dish soap in warm water handles most juice and food spills. Dab it on with a white microfibre cloth. White matters here: a coloured cloth can transfer its own dye onto damp upholstery, which replaces one stain with a worse one.
White vinegar for set-in marks
One part white vinegar to two parts water works on older spots. Test it on the underside or a rear panel first and give it a minute, because some fabric finishes react badly. If the colour shifts at all, stop and go back to soap and water.
Baking soda for odour
Dust a thin layer over the surface, leave it for half an hour, longer for anything stubborn, then vacuum it off. Leaving it overnight is fine and occasionally necessary. This deodorises rather than disinfecting, which is the right trade for something a child sleeps on.
Never machine-wash the foam itself
This sounds obvious until somebody tries it, usually with a loose cushion rather than the full module. Foam is an open-cell structure. Submerging it fills those cells with water, and getting the water back out takes days of air movement rather than one spin cycle. Meanwhile the trapped moisture is doing exactly what you would expect in a warm room.
Spot clean the core with a barely damp cloth and mild detergent, blot the area dry with a towel, and stop there. Never wring it. Compressing wet foam damages cell walls that were never designed to be squeezed while saturated.
Drying
This is where most ruined pieces were actually ruined. Foam that goes back into its cover while still damp will develop mildew in the middle, and by the time you smell it the module is finished.
Let the foam air out in a ventilated spot until it is genuinely dry right through, not just dry on the surface. A fan speeds this up considerably. A hairdryer on a cool setting helps with the cover, though heat settings should stay out of it. If you can leave the pieces apart overnight, do.
Keeping mould out in humid rooms
Foam furniture in bathrooms-adjacent rooms, basements or tropical climates needs a different baseline. Give the pieces space from walls so air moves behind them, keep them off damp floors, and let sunlight reach them occasionally. Direct sun fades fabric over time, so this is a trade-off worth managing rather than avoiding entirely.
Repeated vacuuming helps here too, because organic dust and skin particles are what mould feeds on. A clean piece of foam in a damp room outlasts a dirty one in a dry room more often than people expect.
For spaces where regular deep cleaning matters, choosing pieces with fully removable covers on modular play blocks saves you from doing the fixed-upholstery routine at all.
Frequently asked questions
Can you put kids sofa covers in the washing machine?
Yes, if they are designed to come off. Cold water on a gentle cycle, then line-dry. Hot cycles and tumble drying are what cause shrinkage and print damage.
How do you clean a kids sofa without a removable cover?
Vacuum with a brush attachment, blot spills rather than rubbing, use a few drops of clear dish soap in warm water on a white cloth, and try diluted white vinegar on older marks after testing a hidden area first.
Can you machine wash the foam?
No. Soaking fills the open cells and the water will not come back out in a spin cycle. Spot clean with a lightly damp cloth and dry thoroughly with moving air.
How do you get the smell out of a foam couch?
Sprinkle baking soda over the surface, leave it 30 minutes or overnight for persistent odours, then vacuum it off. Address dampness too, because lingering smells in foam usually mean something stayed wet rather than that the surface was dirty.
How long does a foam sofa take to dry after cleaning?
Surface drying takes a couple of hours in a ventilated room. Drying through to the centre takes considerably longer, and reassembling while the middle is still damp is how mildew starts. Leaving the pieces apart overnight is the safe default.
Does vinegar damage foam?
Not in a diluted solution used sparingly for spot treatment. Do not saturate anything, and test on fabric first since some finishes and prints react to it.