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Upgrade Your Pop-Top SleepEnjoy custom-fit comfort with our Pop-Top Roof Mattress. Choose CoolTech or TENCEL® cooling covers—both zip-off and washable. Prefer durability? Go with 5 easy-clean or 8 waterproof cover options. Built to fit. Ready for adventure.
High density firm foam RG50 is a high-density, firm foam ideal for heavy-duty support. It’s commonly used in seat cushions, gym mats, and other applications where durability and strong support are key. This is the perfect foam for thin Pop-top or Roof-Tent mattresses.
Foam is made in 3 sections, Central section RG50 supports occupants mid section head and foot of mattress Reflex 40 provides soft level of support were its needed.
Most popular High density firm foam. Suitable for seating perfect for sofas, dining chairs, boats, caravans, and camper van seating and mattresses. Best choice for cushions 3–4 inches thick. May be too firm for cushions above 5” in thickness
High density, medium firm foam Reflex 40h is a high-quality foam known for lasting comfort and support. It bounces back quickly and keeps its shape for years—perfect for sofa cushions, armchairs, or even as a mattress.
This product is made by laminating RX38 firm blue foam with a 1″ layer of memory foam. It is essential that the total thickness (C) is greater than 1″. If you order this product at exactly 1″ thick, it will consist of memory foam only
IMPORTANT GRADE INFORMATION This product combines Reflex 40 medium foam with a 1″ layer of memory foam. If you order at 1″ thick, you’ll receive memory foam only — without the Reflex 40 support layer. To ensure proper comfort and support, the total thickness must be greater than 1″.
IMPORTANT GRADE INFORMATION This product combines Reflex 40 medium foam with a 2″ layer of memory foam. If you order at 2″ thick, you’ll receive memory foam only — without the Reflex 40 support layer. To ensure proper comfort and support, the total thickness must be greater than 2″.
GelFlex 50 is a premium gel-infused memory foam designed to reduce heat build-up while delivering outstanding pressure relief and long-term durability. With a high 50kg/m³ density, excellent airflow, and a stable medium-firm feel, it contours comfortably to the body without trapping heat or sagging over time. Fully Crib 5 fire-retardant, it’s ideal for mattresses, toppers, […]
SFV 50 is a high-density viscoelastic memory foam offering excellent pressure relief with a stable medium-firm feel. With a density of around 50 kg/m³ and reliable shape recovery, it contours to the body while providing consistent support and comfort. Fully Crib 5 fire-retardant, it’s well suited to mattresses, toppers, seating, and contract or domestic upholstery […]
High-quality UK-made, heat-sensitive foam that softens and moulds to your body, offering pressure-relieving comfort. Commonly used in mattresses, toppers, pillows, wheelchair cushions, and medical products.
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Our custom size pop-top roof mattresses are made to order for campervan pop-top sleeping areas, where limited thickness and roof clearance make foam choice critical. Customers can configure a custom-sized pop-top mattress, order a full replacement mattress, or choose a separate topper — however, not all foam grades perform correctly in thin pop-top applications.
Because most pop-top mattresses are 5cm thick or less, selecting the right foam grade is far more important than simply choosing what feels soft.
In thin mattresses, low-density or soft foams compress too easily and allow you to feel the base board beneath. This results in:
Poor support
Pressure points
Broken sleep
Premature foam fatigue
For this reason, higher-density, firmer foams perform significantly better in pop-top roof beds, particularly where thickness is restricted.
In simple terms:👉 Support belongs in the mattress. Comfort is added separately. When it comes to ordering a Custom Size Pop-Top Roof Mattress
Pop-top roofs used in UK campervan conversions vary widely in size, layout, and mattress depth allowance depending on the vehicle and conversion company. Customers commonly order custom size pop-top mattresses for vans converted by UK specialists such as Reimo, SCA, Austops, Skyline, and Westfalia-style conversions, where roof bed dimensions and folding clearances differ.
Because there is no single standard pop-top mattress size, each mattress is made to measure to suit the specific roof bed. This ensures:
Correct fit within the pop-top frame
Proper folding when the roof is closed
Best use of available roof clearance
Reliable long-term support
Choosing the correct foam grade is critical in pop-top roof beds, especially where mattress thickness is limited. In thin applications, higher-density foam consistently outperforms lower-density alternatives.
RG50 is the best-performing option for pop-top roof mattresses, particularly at thinner thicknesses.
Very high-density, extra-firm support foam
Performs exceptionally well in thin mattresses
Resists bottoming-out far better than lower-density foams
Ideal for frequent use and heavier loads
Where roof clearance allows, RG50 is our first recommendation for customers who want maximum support, durability, and long-term performance from a pop-top mattress.
Tri-Zone support combines a firm support base with targeted zoning.
Zoned firmness for shoulders, hips, and legs
Improved pressure distribution
Maintains strong overall support
This option suits customers who want slightly enhanced comfort while retaining the firm support required in thin pop-top mattresses.
RX39 is a firm support foam but is not our default recommendation for pop-top mattresses.
Firm foam with lower density than RG50
Suitable for lighter-use or budget-led applications
Adequate performance, but reduced resistance to compression over time
RX39 should be viewed as one option among several, rather than the go-to choice, particularly where long-term durability is a priority.
Where roof clearance allows, a combination mattress can be a practical compromise.
These typically include:
A firm support base (RG50 or Tri-Zone)
A thin comfort layer on top
Combination builds allow comfort to be added without sacrificing the structural support required in pop-top roof beds.
Memory foam should not be ordered as a full pop-top mattress core on its own.
At thin thicknesses, memory foam:
Compresses too easily
Traps heat
Lacks structural support
For this reason, memory foam should only be used as a topper, or as part of a combination mattress, sitting above a firm support layer such as RG50.
If extra comfort is required, the most effective solution is to pair your mattress with a Custom Size Memory Foam Topper.
Using a topper allows you to:
Add pressure relief without altering mattress support
Choose foam grade and thickness independently
Remove or store the topper when travelling
Upgrade comfort later without replacing the mattress
This approach offers the best balance of support, comfort, and flexibility for pop-top roof beds.
Pop-top beds are prone to heat build-up and condensation, particularly where the mattress sits directly on a solid base. To help manage this, many customers add an AirMat / Moisture Reducing Mattress Spacer beneath the mattress.
The AirMat:
Promotes airflow beneath the mattress
Helps manage heat and moisture
Reduces condensation in cooler conditions
Adds light, evenly distributed support without bulk
At just 8mm thick, it provides far more effective support than an equivalent thickness of foam, while allowing the mattress to breathe.
Roof clearance is always a consideration in pop-top sleeping areas. The firm foam grades recommended here help minimise unnecessary thickness while still providing proper support.
If a topper is added for extra comfort, headroom will be reduced when the roof is closed. In these cases, many customers:
Store the topper in the main campervan area while travelling
Refit it once parked and the roof is raised
This keeps the pop-top practical without sacrificing comfort at night.
Choosing the correct cover is just as important as choosing the foam.
Breathable polyester fabric
Promotes airflow for cooler sleep
Zip-off and removable
Cost-effective everyday option
Made from natural, sustainable fibres
Excellent moisture control
Feels cooler and smoother against the skin
Ideal for warm sleepers and summer touring
Water-resistant outer layer
Helps protect against moisture and condensation
Practical for year-round use
Wipe-clean surface
Durable fabric
Ideal for high-use or family campervans
All mattress covers are fully removable and machine washable at a low temperature (30°C).To protect the fabric, stitching, and zip, covers must not be tumble dried. Always air-dry naturally before refitting.
If you’re comparing options or building the right sleep setup for your campervan, you may also find these products useful:
If you don’t require a custom size, our Pop-Top Roof Mattress is available in the most popular standard size and follows the same firm-foam principles recommended for thin pop-top beds.
If your existing mattress provides adequate support but lacks comfort, a Pop-Top Memory Foam Mattress Topper can be added to improve pressure relief without replacing the mattress.
Because customers can configure size, foam grade, thickness, mattress or topper, it’s important to understand that:
RG50 is the best-performing choice for thin pop-top mattresses
Tri-Zone offers structured comfort with strong support
RX39 is suitable in limited applications, not the default
Memory foam belongs in the topper, not the mattress core
Ventilation belongs underneath the mattress
Following this approach delivers better sleep, longer lifespan, and fewer compromises in pop-top roof beds.
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