A custom mattress for caravan or motorhome needs more information than a normal bed size. Leisure vehicle and boat sleeping areas often include tapered sides, rounded corners, wheel arch cut outs, lifting panels and restricted access. A mattress can be the correct maximum width and length yet still fail to fit because the shape or orientation was not recorded.
The All Foam online builder prices Single, Double, King Size and Super King constructions. Non standard dimensions and shaped mattresses for caravans, campervans, motorhomes and boats require contact with the team before ordering.
This guide explains how to measure the space, plan a template, choose depth and layers, and account for ventilation and access.
Decide what is being replaced
Start by identifying whether you are replacing a complete mattress, a thin cushion set, a folding bed pad or a topper.
A mattress is a complete sleep surface with its own support and comfort construction. A topper sits on an existing mattress and cannot replace a weak or uneven base. Seat cushions used to form a dinette bed may need separate pieces that also work when the seating is assembled.
Photograph the current setup in both daytime and sleeping configurations. Record how each section moves, where it stores and which surfaces support it.
If the existing mattress fits well, it can help create a template, but do not copy its thickness or firmness automatically. Old foam may have compressed and rounded at the edges.
Measure the supporting platform first
Remove bedding and, where practical, lift out the old mattress. Measure the actual platform or frame that will support the new product.
Record the maximum length and width, then measure at several points. Boat berths and vehicle beds often narrow towards the foot or curve along a wall. A single width cannot describe that shape.
Check whether the platform is level. Hinged panels, access lids and joined seat bases can create steps or gaps. The mattress needs even support across its full area.
Mark any part that must remain accessible, such as a water tank hatch, storage lid or equipment panel.
Draw the shape from above
Create a clear top view drawing. Mark head, foot, left, right and the side facing upwards.
Add every straight edge, curve, taper and cut out. Use fixed reference points so the position of each feature is clear. For example, give the distance from the head to the start of a wheel arch and the distance from the side to its deepest point.
Do not rely on a photograph alone. Perspective can change apparent proportions. The drawing should be understandable without the photograph.
Use centimetres and write the unit beside every dimension.
Use a full size template for complex shapes
A full size paper or card template is the safest way to describe a berth with multiple curves or irregular sides.
Fit the template directly into the sleeping area and trim it until it lies flat without forcing. Mark the final cut line and orientation on the template. Add the customer name and a reference to the vehicle or boat.
For a two piece berth, make a separate template for each part and mark how they join. If the pieces are mirror images, still label each one individually.
Ask the All Foam team how the template should be supplied before posting or delivering it.
Measure tapers accurately
A caravan island bed or boat berth may be wider at the head than the foot. Record the width at the head, foot and several points between them.
Measure each width at a known distance from the head. For example, record the width every 25cm or at every change in the side profile. Also measure the left and right edge lengths.
Do not assume the taper is centred. Furniture, hull shape and vehicle fittings can make one side different from the other.
Where the curve is irregular, use a template rather than trying to calculate an angle.
Record rounded corners and cut outs
Rounded corners need more than a note saying rounded. Trace the curve with a template or provide measurements from two straight reference edges.
For a wheel arch, cabinet or pillar cut out, record width, depth and position. Mark whether the cut out continues through the full mattress depth or only affects the base platform.
Check whether bedding needs room to tuck around the edge. A mattress that fits the platform exactly may still be difficult to dress when it sits tightly between walls.
Do not subtract an arbitrary allowance. Ask All Foam what finished fit is appropriate for the cover and material.
Check access before choosing one piece
A one piece mattress can fit the berth but fail to pass through a caravan door, motorhome aisle or boat hatch.
Measure the narrowest access point, including door frames, turns, steps and overhead restrictions. Remember that a finished mattress has depth and may not bend sharply without damage.
A split mattress can make installation easier. The split may follow an existing platform join, centre line or lifting section. Decide whether two equal pieces or shaped sections are more practical.
Mark the split on the drawing and consider how the pieces will be held together by the cover, protector or fitted sheet.
Choose the finished depth
Depth affects comfort, weight, storage and headroom. The All Foam custom builder offers 8, 9 and 10 inch constructions for standard UK sizes. A non standard mattress may need a different confirmed specification.
Measure the distance from the platform to overhead lockers, windows, side panels and the lowest point of a lifting roof. Sit and lie in the space to check clearance.
A deeper mattress may prevent a bed from folding, reduce guard rail height or block a cupboard. A very shallow mattress may not provide the support and comfort expected.
Discuss the intended use, sleeper weight and available depth with All Foam rather than choosing the maximum thickness automatically.
Select one, two or three layers
The standard custom foam mattress builder allows one, two or three layers.
A one layer mattress uses one foam grade through the full depth. This creates a simple, consistent response.
A two layer mattress separates the support base from the upper comfort layer. This is a common way to combine a stable foundation with a different surface feel.
A three layer mattress adds a middle transition or comfort layer. It gives more control, but more layers are not automatically better.
The online builder keeps the base at least 6 inches deep and each additional layer at least 1 inch. Non standard sizes and shapes need confirmation before those rules can be applied.
The how many mattress layers guide explains the role of each construction.
Compare memory foam and Reflex foam
Memory foam responds slowly to heat and pressure and follows the body more closely. It is usually selected as an upper comfort layer rather than a full support base.
Reflex foam recovers more quickly. Reflex Medium gives a responsive medium feel, while Reflex Grey provides firmer support and quicker recovery than memory foam.
In a compact bed, think about how easily you need to turn and move. Some people prefer the settled contouring of memory foam, while others prefer the faster response of Reflex.
Read the memory foam versus Reflex foam guide before choosing a comfort layer.
Other foam grades in the builder
Medium foam provides a balanced, less firm feel. High foam provides a firmer and more stable support base. Severe Very Firm is the firmest selectable grade and should be chosen only when a distinctly rigid feel is required.
The correct grade depends on the complete build, not the vehicle type alone. A boat mattress does not automatically need the firmest foam, and a caravan mattress does not automatically need memory foam.
Compare the verified material information on the foam data sheets and ask for guidance when the application has technical requirements.
Plan ventilation beneath the mattress
Condensation is a major concern in caravans, motorhomes and boats. Warm moist air can meet a cold platform and collect beneath the mattress.
Keep fixed ventilation openings clear. Where the bed design allows it, provide air movement beneath the mattress and lift the bedding to air the surface. Inspect the underside regularly for moisture.
Do not place a new mattress over a damp, mouldy or contaminated platform. Identify and correct leaks or condensation problems first.
Boat and leisure vehicle safety ventilation must never be blocked by foam, bedding or storage. Follow the manufacturer guidance for the vehicle or vessel.
Consider the bed base material
A solid plywood platform can support foam evenly but may restrict airflow. Slats can improve air movement but must be close and strong enough to support the mattress without local dipping.
Plastic springing systems and ventilated underlays are used in some leisure beds. Confirm that the support is compatible with the mattress and does not create unsupported gaps.
Check hinges and access panels. The mattress should not be pinched by moving parts or forced over raised fittings.
A damaged or flexible base can make a new mattress feel uneven.
Think about removable covers and bedding
A shaped mattress may need a fitted or zipped cover that follows the same outline. Confirm whether the quoted product includes a cover and how it can be removed or cleaned.
Standard fitted sheets may not fit a tapered or cut out mattress. A flat sheet can be easier, but it still needs enough material to stay secure.
Measure the combined mattress depth when choosing a protector. A protector that is too tight can pull corners upwards.
Check care labels before washing any cover. A zip does not always mean the cover is machine washable.
Weight and handling
Large foam mattresses can be awkward to lift in a confined space. Depth, density and size all affect handling.
If the mattress needs to be lifted regularly for storage access, a split construction may be easier. Add lifting straps only if they are designed for the finished product and do not damage the cover.
Do not drag foam across sharp fittings. Protect corners and clear the access route before installation.
Ask All Foam about approximate handling considerations for the proposed build if frequent lifting is expected.
Fire and application requirements
Caravans, motorhomes and boats may be subject to product, insurance or safety requirements that differ from a domestic bedroom. The suitability of foam for a complete finished mattress depends on more than the foam grade alone.
Tell All Foam the exact intended use. Review the data sheets and any requirements from the vehicle, boat, insurer, hire operator or relevant authority.
Do not assume that a material described as fire retardant is suitable for every regulated application. Fire retardant does not mean fireproof.
Custom product returns
A shaped mattress is made to the supplied dimensions and is normally a customised product. All Foam states that bespoke cut to order and customised products cannot normally be exchanged or refunded when they are not damaged, defective or incorrect.
Memory foam products also have hygiene related return restrictions. Read the current delivery and returns policy before approving the order.
Check every measurement, template and orientation mark. Ask for written confirmation of the agreed specification.
Information to send All Foam
A complete enquiry should include:
- Caravan, motorhome, campervan or boat use.
- Finished width, length and depth.
- A top view drawing with orientation.
- Full size templates for curves and cut outs.
- Details of the supporting platform.
- Preferred firmness and comfort response.
- One piece or split construction preference.
- Door, stair, aisle or hatch restrictions.
- Ventilation arrangements beneath the bed.
- Any relevant fire or technical requirement.
Photographs are helpful when they support accurate dimensions.
Final answer
A custom foam mattress for a caravan, motorhome or boat must be measured as a three dimensional product. Record the full shape, orientation, depth, support platform and access route. Use a template for irregular curves and consider a split build when installation or lifting would be difficult.
Choose foam layers after the shape and practical limits are clear. Keep ventilation openings clear, prevent moisture beneath the mattress and confirm any application specific requirements.
The online builder is for four standard UK sizes. Contact All Foam before ordering any non standard or shaped mattress and review the custom product terms carefully.