How Our Composite Doors Are Made

Composite GRP door designed to last

Our composite doors are constructed to a very high standard designed to be stable, highly insulating and long lasting.

Our composite door range starts at £950 fully fitted and that includes VAT.


composite door construction

1 Tough Outer Skin

Compression moulded facings made from GRP (glass reinforced plastic) with textured finish – see more below

2 Injected Insulating Foam

Polyurethane foam provide stability and is 6 times as insulating as solid timber and bonds to stiles and reinforcings – see more below

3 Reinforcement and Outer Edges

Timber reinforcing protected by trimmable outer PVC composite top, bottom and stiles – timber is never exposed – see more below

More about the outer skin construction of these composite doors

The external skins are manufactured from three components: (a) a sheet moulded compound (b) a thermosetting resin and (c) a glass-reinforced polymer. The skins, 2mm thick, are stable over a wide range of climate conditions and will not expand or contract with temperature changes.

More about insulating and stabilising foam core

Our doors are injected with a 100% CFC-Free polyurethane foam which fills the space between the skins. This provides excellent thermal insulation – six times that of timber and also enhances the door’s sound proofing.

More about the trimmable edges and reinforcing

A 25mm timber rail is inserted directly behind the the polymer rails, top and bottom and a 30mm by 50mm timber lock block is placed behind the timber rail.

No timber is exposed on any side of the door even if the door is trimmed to its maximum extent of 20mm.

Pricing of composite doors

Please enquiry directly to Topline for composite door pricing. We try to keep our prices as low as possible so pricing on composite doors is under continuous review. Please phone us on 0800 652 5663 (free phone from landlines).