Hi Jeremy,

Many thanks for your question about John Lewis mattresses, in particular, if they should sag and become uneven after a months use.

The quick answer is no they shouldn't be so uneven and saggy so quickly. Let's delve a bit deeper into mattress settlement and how to fix or prevent an even mattress.

Mattress Settlement Explained:
All mattresses will settle over the first 3- 6 months of use. This is because the fibres compress and will reach their final resting point. This is natural will all upholstery whether a mattress, bed base, sofa or recliner.
The way to prevent this becoming an issue, as it may have for you, is by following two top tips with a new mattress.

1. Choose a two sided mattress
2. Turn and flip the mattress each month

It really is important when choosing a new mattress that you pick a two-sided model. This then means you have two sides of the mattress that you can use. Meaning twice the sleeping surface to play with to even out mattress settlement.
This also means that you can turn and flip the mattress. This helps even out the settlement and prevent you from sleeping in the same position each night which over time leads to settlement/dips on those very spots where you frequently sleep.

We are creatures of habit when we sleep so rotating and turning the mattress helps even out this natural settlement. It's particularly important during the first year of mattress ownership. After this all settlements should have occurred. By turning the two sided mattress you help spread this out over the whole mattress surface and not just one part.

Given the issues you're having with your John Lewis mattress it may be that either the spring tension is incorrect for your body weight. It's important when buying a quality mattress that you choose the spring tension based on the weight tolerances of the spring gauges. Spring tensions don't relate to the feel of the mattress but the support they provide. So a medium gauge pocket spring doesn't actually mean a medium feel mattress. A lot of people get confused by this.

Spring Tension	Wire diameter (Gauge)	Weight Range
Soft	1.2mm	Bespoke Tension (Please Call)
Medium	1.4mm	Upto 16 stone
Firm	1.6mm	16 stone plus
Extra Firm / Orthopaedic	1.9mm	20 stone plus

The feel of the John Lewis mattress is always provided by the upholstery layers and not spring tension. Have a look below at the different fibres and how each feels. The way they are layered results in the feel.

Upholstery Layer	Fibre Type	How it will feel?	Price Point
Polyester	Synthetic	Soft	Cheap
White Fibre	Synthetic	Soft/Medium	Cheap
Recycled Fibre / Eco Fibre	Synthetic	Medium	Cheap
Memory Foam	Synthetic	Medium/Firm	Mid Price
Igel / Hybrid Foam	Synthetic	Medium/Firm	Mid Price
Polycotton	Synthetic/Natural Blend	Soft/Medium	Mid Price
Linen	Synthetic/Natural Blend	Medium	Mid Price
Wool (Pure)	Natural	Soft/Medium	High-End
Cotton (Pure)	Natural	Soft	High-End
Silk	Natural	Soft	Expensive
Horsehair	Natural	Medium	High-End
Mohair	Natural	Medium/Firm	High-End
Hemp	Natural	Medium	High-End
Latex (100% Natural)	Natural	Medium/Firm	High-End
Coir	Natural	Firm	High-End
Flax	Natural	Firm	High-End
Coarse Cashmere	Natural	Firm	High-End
Bamboo	Natural	Super Soft	Expensive / Exclusive
Horsetail	Natural	Firm	Expensive / Exclusive
Alpaca	Natural	Soft	Expensive / Exclusive
Cashmere (Pure)	Natural	Soft	Expensive / Exclusive
Vicuna	Natural	Super Soft	Expensive / Exclusive

What to expect based on your mattress budget:

We can appreciate Jeremy that you may have spent a considerable amount on your John Lewis mattress. If it has sagged its worthwhile getting in touch with them directly to discuss how to remedy the solution. We have also provided below a solid idea of what to expect for your budget and how what may feel like an expensive mattress may actually still only be entry-level once all the marketing and advertising costs have been taken off them.

How much to spend on a double mattress?	What can I expect for my money?
Under £500	Will not get you much at best a 13.5 gauge open coil/cage sprung with a thin polyester layer or a solid foam mattress.
£500	Entry level spunbond springs with some form of synthetic upholstery. Usually one sided mattresses.
£750	The beginnings of a basic pocket springs unit with 800 – 1000 count. No substantial amount of filling other than foams and synthetic materials. Two sided models.
£1000	Should get you away from most low ranges and into the mid-range pocket spring models.
£1250	Should get you a decent pocket sprung mattress with some Natural Fibre content.
£1500	Should get you many manufacturers mid-range models with Natural Fibres
£1500-£2000	Should get you a Hand Made primarily Natural Fibre Quality Mattress
£2000+	You should expect 100% Natural Fibres and Traditional Hand Made Construction Method.
£5000+	A Bespoke Hand Made Sleep System, High-end Spring Units & Featuring the Worlds Most Luxurious Natural Fibres.

Our advice would be to get in touch directly with John Lewis and ask for an inspection of the mattress as it shouldn't be sagging so quickly. Also, check that the spring tension is suitable for your body weight.

We hope that helps and gives you further mattress buying guidance. If you have any more mattress related questions please get back in touch on info@localhost or 0161 437 4419.

Sleep well!
John & Ryan