Polycarbonate or Fabric for a Retractable Roof

Once a client has decided on a retractable roof, the next question is what the roof is made of. The two practical choices are rigid polycarbonate panels that slide, and a tensioned fabric membrane that folds back. They behave differently enough that the space itself usually decides.

How the two behave

1. 01

   Daylight

   Polycarbonate transmits light, so a closed roof still feels bright and the space below reads as a conservatory. Fabric blocks direct sun and gives shade; closed, the space reads as a covered room.

2. 02

   Heat

   Daylight brings warmth with it. Under polycarbonate in a Delhi summer afternoon the space heats up unless it is ventilated or shaded. A fabric membrane keeps direct sun off entirely.

3. 03

   Rain noise

   Rain is louder on rigid panels than on a tensioned membrane. Over a bedroom terrace or a restaurant that is a real consideration; over a car park it is irrelevant.

4. 04

   Weight and span

   Fabric is lighter and folds on itself, which helps on longer openings and keeps manual operation comfortable further. Polycarbonate is heavier and reaches the practical manual limit sooner.

Where polycarbonate is the better choice

• Terraces and sit-outs that would feel like a cave under solid shade.
• Spaces where you want the glass-roof look while still being able to open it.
• Smaller openings, where the extra weight is not a problem.
• Where the roof stays closed most of the time and daylight matters more than heat.

Where fabric is the better choice

• Restaurants, banquet lawns and hotel courtyards where guests sit for hours.
• Swimming pools, where shade and UV control are the point.
• Larger openings, where weight and travel distance start to dominate.
• Anywhere the roof is opened and closed often, especially by hand.

Upkeep is not the same either

Both need cleaning, and both should be inspected before and after the monsoon. Polycarbonate panels are wiped down and the track kept clear of grit, which is what usually causes stiff operation. A membrane is washed down and checked for tension and for wear at the fixing points, and its life depends on the coating family chosen. Our maintenance guide sets out the schedule for membranes, and the materials guide explains how PVC, PVDF, PTFE and ETFE differ.

Questions worth answering before you decide

• Do you want daylight coming through the closed roof, or shade under it?
• Will people sit under it for hours, or pass through?
• Is the opening long and narrow, or close to square?
• Will it be opened by hand or by remote? Weight matters more for manual.
• Does rain noise matter for what happens below?

Common questions

Can the two be mixed on one structure?

Yes, on separate bays. A courtyard can have a fabric roof over the seating and a polycarbonate section over a walkway, provided each bay is engineered for its own material.

Which lasts longer?

Both are engineered products with a long service life, and both depend far more on installation quality and upkeep than on the material alone. A membrane's life tracks the coating family; a polycarbonate roof's tends to track its track hardware and fixings.

Does polycarbonate yellow over time?

Quality sheet carries a UV-protected face that resists it, and that face must be installed the right way up. This is one of the places where cheap sheet and careless installation show themselves early.

Which is better for an Indian summer?

For sitting under, fabric: it keeps direct sun off and the space cooler. For brightness in a smaller space you mostly pass through, polycarbonate is pleasant, provided the area is ventilated.

If the operation side is still open, read manual or motorised next, or send us photographs of the space.