Rock Hard Super Firm Foam Mattress
- In-stock
- Finance available
- Free delivery
- Returns
- Feature: Hypoallergenic
- Comfort: Memory Foam
- Type: Rolled
- Feel: Firm
- Brand: Mattress Online
From £319.00
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BedBoy Score
A composite score drawn from aggregated customer sentiment across verified reviews, with construction-type benchmarks for categories where reviewer commentary is limited. See our scoring methodology.
across 8 measured categories
Per-category breakdown below. The composite is the unweighted mean of every scored category, rounded to one decimal place.
- Brand
- Mattress Online
- Retailer
- Mattress Online
- Delivery time
- Good
- Customer sentiment
- Excellent
- Guarantee
- Excellent
About the Rock Hard Super Firm Foam Mattress
Last checked
Sleepers deliberately moving away from soft, cushioned mattresses are the obvious audience for the Rock Hard Super Firm Foam Mattress. It is a 23cm, spring-free reflex-foam model with a firm, 5 of 5 feel, a knitted removable cover, hypoallergenic treatment and a rolled delivery format. The construction is plain but purposeful: one solid foam support block rather than pocket springs, mini springs or layered comfort foams, so the feel is uniform from shoulder to heel and there is very little of the buoyant lift associated with traditional sprung mattresses. Honest spec for a hard-support mattress. Reflex foam at this tension is a conservative material choice compared with memory-foam hybrids or the £700-plus pocket-sprung tier, but it suits the brief because it resists deep sink and keeps the surface flatter under load. The “orthopaedic” claim here comes from firmness and surface consistency, not zoned engineering or pressure-mapped support, which means the mattress is bluntly supportive rather than body-profile aware. The removable cover is useful, although the cover guarantee runs for 12 months while the mattress warranty is 10 years, leaving the zip, fabric or wash wear on a much shorter protection window than the foam core. Single-sided care keeps rotation simple, but it also means there is no second sleeping face to use if impressions develop.
Reflex foam with no springs makes this best aligned with back sleepers and some front sleepers who want a flat, unyielding surface, especially those who feel under-supported on softer foam or open-coil mattresses. Happier accounts repeatedly describe the firmness as matching the description, with several linking the hard feel to reduced back discomfort, and one substantial review from a 130kg sleeper says the block holds weight better than softer mattresses that had previously compressed. The lack of bounce is part of the appeal. Couples may also prefer the muted movement of a foam block over a spring unit, although the same dense construction is repeatedly described as heavy, so moving it upstairs or rotating it can be a two-person job despite the rolled delivery. Pressure is where the fit narrows: side sleepers and curvier builds need more give at the shoulder and hip, and a low-scoring account specifically flags pain in those areas, which matches what the spec implies. The bigger contradiction is durability; the product is sold as a highly durable support block, yet low-scoring accounts include repeated early softening and sagging towards the middle, so the 10-year warranty should not be read as a promise that every sleeper will get a decade of unchanged firmness. For dedicated back sleepers wanting a hard, low-bounce foam block, this is the right call. For side sleepers, pronounced hip-and-shoulder pressure or a more adaptive surface, look at softer pocket-sprung or memory-foam hybrid tiers instead.
Pros and Cons
Pros
- Firm support reduces back pain for those who prefer a solid sleeping surface.
- Dense foam construction provides consistent support without any sagging over time.
- Orthopaedic support helps with body alignment and alleviates discomfort for heavier sleepers.
- Single-sided design simplifies maintenance, requiring only rotation every three months.
Cons
- Excessive firmness causes discomfort for lighter sleepers and those with shoulder or hip pain.
- Some customers report loss of support after a few days of use, leading to sagging.
- Heavy weight makes it difficult to move, especially for users without assistance.
- Limited adaptability may not suit those used to softer mattresses or different sleeping styles.
Price Tracker
Written by
Giselle Green, Editor in Chief
Last checked by Giselle Green on . Scoring follows our scoring methodology.
Specifications
Manufacturer specifications without the jargon, easy to scan and compare.
Extra Firm
Boasting an 'Extra Firm' rating, this mattress offers unparalleled support, ideal for individuals who prefer a structured sleeping surface or those with certain back conditions. However, be mindful, as it may fall short on plush comfort characteristic of softer options, potentially making it less suitable for side sleepers or those who favour a more cushioned feel.
Knitted cover
A knitted cover spells out a blend of cosiness with breathability, providing a comforting touch that many crave while ensuring your temperature remains well regulated throughout the night. This feature pairs comfort and functionality in a coveted balance, contributing to an intimate sleep environment that is warm, inviting, yet refreshingly aerated.
Rolled-up
Embracing a rolled-up design, this marvellous piece of sleep engineering ensures direct delivery from manufacturer to home, eliminating the need for any intermediary handling. This design also helps to consolidate both space and cost, but be aware it may require up to 48 hours to fully expand and reach optimal comfort levels.
10 Year Warranty
A 10-year warranty essentially serves as a long-term promise of quality, guaranteeing that the item is free from any manufacturing defects and will perform as expected for a decade. If any issues arise during this period, they'll be rectified at no extra cost, assuring you of a hassle-free sleep experience for years to come.
Reflex Foam
Reflex foam, characterised by its solid and supportive nature, aids in even weight distribution, thus minimising pressure points and improving your body alignment during sleep. However, it's worth noting, this type of foam tends to retain heat, which may not be optimal for those who prefer cooler sleeping environments.
Orthopaedic Support
This king-size sanctuary of comfort grants sterilised hypoallergenic filling that ensures sleep is not disrupted by common allergens. Furthermore, an impressive tally of 2000 individually nestled springs provides the spine with correct alignment, tackling backaches and promoting a healthy sleeping posture.
Fire Resistant
Ensuring safety during your peaceful slumber, fire resistance is a crucial feature that reduces the risk posed by potential accidents involving flammable materials. Furthermore, it demonstrates the manufacturer's commitment to adhere to strict safety standards, prioritizing your well-being over all else.
National Bed Federation Approved Brand
Receiving approval from the National Bed Federation indicates that the product meets specific industry standards and quality benchmarks. This approval serves as a reassurance of the product's reliability and durability, though discerning buyers may still want to consider personal comfort preferences.
Air Vents
Integrated air vents encourage better breathability within a mattress, promoting a cooler night's sleep. Moreover, they simultaneously assist in gently eliminating excess humidity, thus maintaining the mattress’s freshness and longevity.
Depth: 23cm
With a depth of 23cm, this mattress provides ample cushioning for a comfortable night's rest. The generous thickness may also ensure the durability and longevity of the mattress, offering users an investment in both comfort and lifespan.
Includes turning handles
Turning handles aid in the regular rotation of the mattress, thereby significantly extending its lifespan. Easy maintenance is always appreciated, and these handles streamlining the process by making rotation hassle-free and manageable.
Approved by the National Bed Federation
Factory auditing checks that the mattress is made under UK rules for flammability, fillings and labelling, giving you a clearer paper trail for what arrives at home. It doesn't prove comfort, firmness or long-term durability.
10 Year Guarantee
Manufacturer cover deals with faults in the mattress build, such as failed stitching, collapsed springs or a cover defect, giving you a route to claim after purchase. Wear, comfort changes and misuse are usually excluded.
Hypoallergenic
Hypoallergenic mattresses are the perfect choice for those with allergies or sensitivities, as they protect against allergens and irritants. They're also a great choice for those with asthma or respiratory issues.
Memory Foam
Foam in the comfort layer softens under body heat, letting shoulders and hips sink closer into the surface while reducing sharp pressure points. It can feel warmer and slower to move on.
Handcrafted in the UK
Factory workers assemble and finish the mattress by hand, leaving small variations in stitching or edge detail you may notice up close. It doesn't prove better support or longer life.
Single-sided
Bed-making is simpler because the comfort layers stay on the top face, leaving the underside to stabilise the mattress while you lie on the cushioned surface. Don't flip it over.
Removable cover
Zipped fabric casing lets you wash the layer closest to your body, leaving fewer stale odours and marks on the sleep surface. Foam cores cannot go in the machine.
23cm deep
Mattress sides add enough bulk to lift the sleep surface, making fitted sheets sit fuller and the bed feel less low. Very deep sheets may bunch at the corners.
Frequently Asked Questions For The Rock Hard Super Firm Foam Mattress
The questions below are the most common ones BedBoy readers ask when comparing products in this category. Contact the editorial team with a different question, quoting P1958 in the subject line.
Reader reviews of the Rock Hard Super Firm Foam Mattress
BedBoy publishes reader-submitted reviews to broaden the sentiment sample. Reviewer purchase status is not independently verified at submission. For verified-purchase ratings, see the Trustpilot block below. Submit a review, quoting P1958 in the subject line.
Really sturdy and comfortable mattress. Provides the promised orthopaedic support while ensuring a peaceful night's sleep.
Excellent hard mattress quality, something I was looking for!
Ultra firm as advertised. When the memory foam moulds you get a great nights sleep and feel fresh in the morning if this type of mattress is what youre used to or looking for.
It's really as hard as I expected, I love the feel of the mattress
Fully support my back Make me sleep well
Handles
Mattress is really firm
Nice and firm
It is super hard taking time to adjust but my back is thankful ! Great quality and very solid !
Long lasting & hardness
First few weeks, amazing mattress!
It is exactly as it as described in advertising and is providing us with a good nights sleep.
Been sleeping on this mattress for a month now and so far, so excellent! if youre looking for a very very firm mattress without feeling like youre sleeping on a rock, and want full body support, this is THE ONE. Its a very very dense and heavy block of foam (of some sort), gives a feeling of calm when you lie on it, as it has none of the ‘bounce that comes with spring mattresses, and provides whole body support. Yet….it feels soft and comfortable.. Note, its very heavy so if you have an awkward staircase or cant deal with the weight, Id advise you buy the delivery to your bedroom option when purchasing. Go for it, you wont regret :)
We've had the mattress about a month now. very hard as advertised and exactly what we wanted.
It lives up to its description of being rock hard but this is what I needed, however, the mattress still manages to be soft and is very comfortable.
Just Good firm mattress .
very firm
amazing mattress. less sleep needed, body fully rested, optimal hardness
nearly perfect for my back... After one month, so noticeable issues...
It is super firm but still very comfy. I cant say that i am laying on a rock
Verified retailer reviews
Independent Trustpilot reviews of Mattress Online.
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