When to replace a mattress, using the sag and not the birthday

"Every seven years" is a sentence that gets repeated until it sounds like a regulation. It isn't one. Some beds are done at five. Some are dull but honest at ten. The calendar is a weak instrument. The surface is a better one.

Look before you diagnose your back

Stand at the foot of the bed with the sheets off. A shallow cradle where you sleep is normal foam. A dip you can see from the doorway, or a ridge where the edge of your body ends, is the mattress retiring. Put a broom handle or a yardstick across the width. If daylight under the stick is obvious in the middle, you're not imagining it.

Then lie where you don't usually lie, for one night if you can. If the "good" side of a half-used bed feels like a different piece of furniture, the slept-on side is the problem. If both sides feel the same and you still wake up sore, the bed may be fine and the pillow, the hour, or your week may not be. Don't buy a mattress to fix a month.

Smell, stains, and the things a cover can't launder

A new-foam smell fades. A smell that is sweet, sour, or plainly damp does not. That's a reason to replace, not to bake the room in sunlight and hope. Stains that have gone through a protector into the foam are the same category. We won't take a stained Thaw mattress back as a trial return, and you shouldn't keep sleeping in one that grew something. If this is a Thaw bed still inside the warranty and the issue is a split or a broken coil rather than a spill, write with photos. That's a warranty question, not a lifestyle one.

The morning test, kept honest

For a week, write one line: where it hurt, and whether you were on your side, back, or front. If the note is the same place every day and it eases once you're up and walking, the surface is a fair suspect. If the note changes with your workday, or it hurts before you lie down, a new bed is a guess. New or severe pain, pain with numbness, pain after a fall: that's a clinician, not a checkout.

What a topper can still do

Mantle is 5 cm of foam. It can take the harshness off a bed that's too hard and still structurally even. It cannot fill a hole. If the yardstick test failed, a topper makes a lumpy dip into a softer lumpy dip. People do it because the new mattress is a bigger decision. Sometimes the delay is fine. Don't tell yourself it's a repair.

If you do replace it

Measure the frame before you shop sizes. Read how to choose only as far as your actual complaint. Match the feel to the position you spend the night in. Put a protector on the new one immediately. The old mattress needs a way out of the house that isn't "leave it in the rain." Many cities have a bulk pickup. Some shops take the old one when they deliver. We don't, on the current shipping plan. Plan for it before the box arrives, or you'll be living with two mattresses and a hallway.

A short checklist

• Visible sag or a ridge, not just a warm spot in the sheets
• Smell or staining that washing the cover doesn't touch
• Springs you can hear or feel as individual rings
• Waking in the same spot of pain on a bed that fails the yardstick test
• A base with broken slats, which you should fix even if you keep the mattress

Any one of the first four is enough. The fifth is a repair, not a purchase.

Keeping it, on purpose

Not every tired feeling is a purchase. If the yardstick test passes, the smell is clean, and the morning note changes with your week, spend the money on the room: a curtain, a cooler duvet, a pillow you can edit. Rest is cheaper than a mattress and fixes a class of complaints that look like firmness. We've had people ready to order Loom describe a pillow the height of two fists. Start there. If the next month is the same and the bed is still flat, then you've earned the bigger box.

If you keep a bed that's starting to dip because a move is six months away, be honest that you're scheduling the replacement, not solving it. Don't buy a topper to pretend otherwise unless the dip is still shallow. And don't rotate a one-sided bed onto its face because a relative said mattresses should be flipped. Ours have a top. The label side up is the bed.

FAQ

Is a ten-year-old mattress automatically done?

No. Look at it. A guest bed that was slept on twelve times may be fine and unfashionable. A nightly bed with a crater is done even if it's newer than that.

Can flipping it help?

Only if the bed was built to be flipped. Most foam and hybrid beds now have a top and a bottom. Flipping a one-sided bed puts the support layer against you. Rotating it head to foot can even out wear. It will not undo a sag.

Does the Thaw warranty mean you'll replace it when I'm tired of it?

No. The ten years cover faults, not a change of taste and not the ordinary impression where you lie. The trial is the change-of-mind window, and it is 100 nights, not ten years.