Insulated sectional garage doors

Why choose a foam-filled panel over single-skin steel?

A single-skin door is a sheet of steel and little else, so the garage runs at outdoor temperature. A double-skin panel with a polyurethane core slows heat loss, stops the panel drumming in wind and gives a stiffer, quieter door. If the garage is a workshop, gym, utility or store for anything that dislikes damp and cold, insulation is the part of the specification that earns its keep.

What thickness should you pick?

Most domestic sectional doors use panels of about 40 to 42 mm. Doors sold as thermally broken use thicker panels, often around 67 mm, with a break between the inner and outer skins so cold is not conducted straight through. The thicker option costs more and needs a little more headroom, so it makes most sense on integral or heated garages.

How much difference do seals make?

Panels are only half the story. A good door has a flexible bottom seal that follows uneven floors, brush or rubber side seals, a head seal and finger-safe joints with gaskets between sections. A badly sealed insulated door can lose more heat round the edges than through the panels, so seals are checked and set on fitting day.

Will an insulated door help an integral garage?

Where a garage shares walls with the house, a colder garage means colder shared walls and rooms above. An insulated door will not turn a garage into a habitable room, but it does take the edge off, especially paired with a draught-sealed door between the house and the garage.

Is it worth it on a detached garage?

On a detached garage used only for a car, a standard double-skin door is usually enough. If you keep tools, bikes, a freezer or stock in there, or you use it as a workspace, the warmer, drier conditions are worth the extra cost.

Do insulated doors weigh more?

Yes. Foam-filled steel panels are heavier than single-skin doors, which is why every sectional door is balanced by springs sized to that door, either torsion springs on a shaft above the opening or tension springs along the tracks, depending on the range and size. They are set during fitting so the door feels light by hand and the motor is not straining.

How long do the panels last?

Galvanised and factory-coated steel panels are made for many years of outdoor use. Look after the coating with an occasional wash, keep the bottom seal clear of grit and leaves, and book a service every year or so to keep springs and cables in order.

What options are there?

• Panel thicknessTypically 40 to 42 mm double-skin, or thicker thermally broken panels on premium ranges.
• Seals all roundBottom, side and head seals, plus gaskets between sections.
• Electric or manualMost insulated doors are motorised; manual operation is possible on lighter doors.
• Any finishRibbed, flush, cassette, woodgrain and coloured finishes are all available with insulated panels.
• Window insertsAdd glazed inserts for daylight; they slightly reduce thermal performance.

Key facts

Panel construction	Two steel skins with a polyurethane foam core
Typical panel thickness	40–42 mm (thermally broken around 67 mm)
Operation	Torsion or tension springs; electric or manual
Opening	Vertical, parks under the ceiling
Lead time	Made to measure; typically a few weeks
Guide price	£2,095–£3,495 inc VAT

Who is it for?

Best suited to integral garages, workshops, home gyms and garages that share a wall with the house.

Do I need permission?

Replacing a garage door does not normally need planning permission anywhere in the UK. The usual exceptions are listed buildings, conservation areas, Article 4 areas in England and newer estates where planning conditions restrict changes to garages. Planning rules by nation →