Align 1000
FirmFirm Ortho springs and a firmer base keep your spine level. Best for back and front sleepers.
SoftFirm
Choose Align 1000
Two mattresses. Firm or soft.
Pocket sprung mattresses from Sofa Bed Expert. Same 1,000 springs, same 25 cm depth, same price. Choose the feel, then the size.
Choose your mattress
From £399 · Double and King Size · Free delivery
Serenity 1000
SoftA soft comfort layer lets hips and shoulders settle in. Best for side sleepers.
SoftFirm
Choose Serenity 1000
- 1,000 pocket springsin both mattresses
- Cooling gel memory foamquilted into the cover
- Free deliveryin 3 to 4 days
- 14 day returnsFIRA tested
Firm or soft: which mattress should you choose?
Choose the firm Align 1000 if you sleep on your back or front, or wake stiff on a soft bed. Choose the soft Serenity 1000 if you sleep on your side, or find firm beds hard on your hips and shoulders. The spring core is identical in both, so the support underneath is the same. Only the feel on top changes.
- You sleep on your back
- Align 1000 FirmKeeps the lower back level.
- You sleep on your front
- Align 1000 FirmStops the hips sinking and the back arching.
- You sleep on your side
- Serenity 1000 SoftLets shoulders and hips settle in.
- You share and can't agree
- Serenity 1000 SoftUsually the safer compromise.
Why a sofa bed company makes mattresses
“Your sofa bed is more comfortable than our actual bed. Could you make us a mattress?”
We heard it for years after deliveries. So we built a mattress for a proper bed the way we build our sofa bed mattresses: real pocket springs, a cool surface and support that lasts, rather than a slab of foam in a box.
One firm, one soft. Both FIRA tested.
What's inside a Sofa Bed Expert mattress
Quilted gel memory foam 2 cm
Memory foam infused with cooling gel and quilted into the cover. It moulds to your shape and draws heat away from the surface, so the top of the bed stays fresher than plain memory foam.
Flex Comfort Foam 4 cm
The layer that sets the feel. Supportive and firmer in the Align 1000, soft and cushioning in the Serenity 1000. This is the main reason the two mattresses feel different.
1,000 pocket springs 16 cm
Each spring sits in its own fabric pocket and responds to your weight on its own, so the bed follows your body and you feel far less of a partner turning over. Firm Ortho springs in the Align, FlexCore springs in the Serenity.
Flex Support Border edge
A reinforced perimeter around the springs. It gives support corner to corner, so you can sleep near the edge or sit on the side of the bed without it dipping.
Flex Support Foam base 3 cm
A foam base layer that keeps the springs level on any standard slatted frame or divan, and adds a final level of support. Total depth is approximately 25 cm.
Align 1000 vs Serenity 1000
| Align 1000 | Serenity 1000 | |
|---|---|---|
| Feel | Firm, orthopaedic | Soft, cushioning |
| Best for | Back and front sleepers | Side sleepers |
| Springs | 1,000 Firm Ortho pocket springs | 1,000 FlexCore pocket springs |
| Comfort layer | 4 cm supportive Flex Comfort Foam | 4 cm soft Flex Comfort Foam |
| Top layer | 2 cm quilted gel memory foam | 2 cm quilted gel memory foam |
| Edge and base | Flex Support Border, 3 cm foam base | Flex Support Border, 3 cm foam base |
| Depth | Approx. 25 cm | Approx. 25 cm |
| Double 135 × 190 cm | £399 | £399 |
| King Size 150 × 200 cm | £499 | £499 |
| Testing | FIRA tested | FIRA tested |
| Delivery | Free, 3 to 4 days | Free, 3 to 4 days |
Rows in bold are the only differences. Free delivery covers England, Wales and Scotland.
How to choose a mattress for your bed
A short guide to what matters when you buy a pocket sprung mattress in the UK, and how our two models answer it.
What is a pocket sprung mattress?
A pocket sprung mattress has hundreds of small coil springs, each sewn into its own fabric pocket. Because the springs are not wired together, each one moves on its own. The mattress follows the shape of your body more closely than an open coil mattress, and movement on one side of the bed travels far less to the other.
Both our mattresses have 1,000 pocket springs in a 16 cm core, with foam comfort layers on top and a reinforced border around the edge.
Firm or soft: what actually changes?
Firmness is how far you sink before the mattress pushes back. A firmer mattress keeps the body flatter, which suits back and front sleepers. A softer mattress lets the shoulder and hip sink further, which keeps the spine straighter when you lie on your side.
In our range the springs and comfort foam change between the two models. The build, depth and sizes stay the same, so you only choose the feel.
UK mattress sizes explained
A standard UK Double mattress is 135 × 190 cm (4ft 6in × 6ft 3in). A standard UK King Size is 150 × 200 cm (5ft × 6ft 6in), so it gives 15 cm more width and 10 cm more length. Both our mattresses come in these two sizes and fit any standard UK bed frame or divan of the same size.
European sizes differ, so if your frame was bought abroad, measure the inside of the frame before you order.
Why gel memory foam sleeps cooler
Traditional memory foam holds body heat, which is why some people find it warm. Gel infused memory foam carries heat away from the surface. In our mattresses it is a thin 2 cm layer quilted into the cover and sits on a pocket spring core, which lets air move through the mattress far more freely than a solid block of foam.
A bed mattress, not a sofa bed mattress
The Align 1000 and Serenity 1000 are around 25 cm deep and made for a standard bed frame or divan. They will not fold into a sofa bed mechanism. If you want to make a sofa bed more comfortable, our Cool Gel Memory Foam Topper is cut to the sleeping area of Sofa Bed Expert sofa beds and lifts off when you fold the bed away.
Delivery, returns and care
Both mattresses are in stock and delivered free in 3 to 4 days across England, Wales and Scotland. You have 14 days from the day after delivery to return or exchange, plus a 48 hour cooling off period after ordering.
To keep the comfort layers even, rotate the mattress head to foot every few months and use a fitted sheet or mattress protector over the quilted cover.
Questions
What is the difference between the Align 1000 and the Serenity 1000?
The feel. Both have 1,000 individually pocketed springs, a quilted cooling gel memory foam top and a reinforced border, and both are approximately 25 cm deep. The Align 1000 uses Firm Ortho springs with a supportive comfort layer and a firmer base, so it feels firm and orthopaedic. The Serenity 1000 uses FlexCore springs with a soft Flex Comfort layer, so it feels soft and cushioning.
Which mattress is better for back pain?
Many people with back discomfort prefer a firmer surface that keeps the spine level through the night, which is what the Align 1000 is built for. Side sleepers with sore hips or shoulders often do better on the softer Serenity 1000. Anyone with a specific medical condition should ask their GP or physiotherapist what they recommend.
Which mattress is best for side sleepers?
The Serenity 1000. Its soft comfort layer lets the shoulder and hip sink in, so the spine stays straighter when you lie on your side. On a firm mattress, side sleepers often feel pressure at the shoulder and hip.
We share a bed and one of us likes firm, the other soft. Which one?
The spring core is the same in both, so the support is identical. The difference is only the comfort layer. The Serenity 1000 is usually the safer compromise, because a side sleeper on a firm mattress tends to feel it more than a back sleeper on a soft one.
What sizes are available and will they fit my bed frame?
Two standard UK sizes: Double 135 × 190 cm and King Size 150 × 200 cm. Both fit any standard UK bed frame or divan base of the same size. If you are unsure, measure the inside of your frame before ordering.
How much do the mattresses cost?
Both models cost the same: £399 for a Double and £499 for a King Size, with free delivery across England, Wales and Scotland.
How deep are the mattresses?
Approximately 25 cm. That is made up of a 2 cm gel memory foam top, a 4 cm comfort foam layer, a 16 cm pocket spring core and a 3 cm foam base.
Do these mattresses sleep hot?
The top layer is gel infused memory foam, which moves heat away from the surface, and it sits over a pocket spring core rather than a solid block of foam, so air moves through the mattress far more freely than in an all foam mattress.
Can I use one in a sofa bed?
No. At around 25 cm deep they are mattresses for a bed, not for a folding sofa bed mechanism. For a sofa bed, use our Cool Gel Memory Foam Topper, cut to the sleeping areas of our sofa beds.
How quickly is it delivered, and can I return it?
Both mattresses are held in stock, so delivery normally takes 3 to 4 days from your order. Delivery is free across England, Wales and Scotland. You can return or exchange within 14 days from the day after delivery, and there is a 48 hour cooling off period after ordering.
Still unsure? Call us free on 0800 368 8914.
Firm or soft. Double or King.
That is the whole decision. Free delivery in 3 to 4 days and 14 days to change your mind.
