How to Make a Soft Sofa Feel Firmer

Two kinds of fix

Everything on this list does one of two things. Either it makes the cushion itself denser, or it makes the surface underneath it solid. Which one you need depends on where the softness is coming from.

So before you spend anything, take the cushions out and press on the bare seat base. If it sinks under your hand, no amount of cushion work is going to fix your problem.

1. Rotate and flip. Free, buys you a few weeks

If you've never done it, do it today. Cushions compress unevenly because we all sit in the same spot every evening. Rotating spreads that around.

Worth doing every month or so on a newer sofa. On one that's already gone soft you'll get a couple of weeks out of it and then you're back where you started.

2. Add batting inside the cover. Cheap, mixed results

Unzip the cushion cover and wrap the foam in polyester batting, or add a layer of high-density foam. Twenty to fifty dollars in materials.

It makes the cushion plumper and rounder. It doesn't make it lastingly firmer, because polyester packs down fast. And if the seat base underneath has gone, all you've done is add padding over a hole.

3. Replace the foam inserts. Works, but it adds up

New high-density foam cut to size will properly transform a cushion that's broken down. Budget $80 to $200 a seat from a foam supplier, more if you want it wrapped or feather-topped.

Worth every penny when the seat base is solid and only the cushions have gone. Money down the drain when the problem is underneath, because your lovely new foam will sink straight into the same dip.

4. A support board under the cushions. Cheap, and it goes after the actual cause

A rigid board laid on the seat base, under the cushions. Thirty-five to a hundred dollars depending on the size, about a minute to fit, nothing attached and nothing modified.

This is what you want when the seat base has gone soft, which is where most sofas past five years old end up. It doesn't make the cushion denser. It stops the cushion falling through. In practice that's usually what "too soft" actually means.

One catch. It has to genuinely fit. A board matched to your seat, sitting fully inside it with nothing reaching past the front edge, is what spreads your weight evenly across the whole seat, which is why sizing matters more than anything else about this.

5. Reupholstery. The proper repair, at a price

New webbing or springs, new foam, sometimes a new cover. Several hundred to well over a thousand dollars, and a week or two without your sofa.

The right call for a genuinely good piece you plan to keep for decades. Hard to justify on a mid-range sofa that cost less than the repair will.

A quick way to decide

• Seat base firm, cushions collapsed. New foam inserts.
• Seat base sinks under your hand. Support board.
• Both gone, and you love the sofa. Reupholstery.
• Both gone, and you don't. Put the money toward the replacement.

Thirty seconds pressing on that bare seat base will stop you spending a couple of hundred dollars on the wrong fix.