TUBE SPECIFICATION - TUNNEL RANGE

The tube used for our hoop frame manufacture is a high quality, high strength galvanised steel tube.  The tube wall thickness for all frames is 1.5mm or 1.5 gauge.  With considerable experience in frame manufacture and construction we have tuned our tube diameter utilisation to the size and type of polytunnel in our range.  Citadel's frames are strong and durable and our conventional tunnels are single section half hoops giving maximum strength to a robust framework with no need for "joint bracing" as is necessary with some manufacturer's frames.

We are often asked what minimum diameter we use for frame manufacture.  Tube diameters are as follows:

- Standard Conventional Polytunnels up to and including 14' wide:  25.4mm (1") diameter tube.  (As such' ALL starter kit models are manufactured in 25.4mm (1") diameter tube.)

- Hi-Top Upgraded 10' Wide Polytunnels:  31.75mm (1 1/4") diameter tube.

- Maxi Conventional 12' and 14' Wide Polytunnels: 31.75mm (1 1/4") diameter tube.

- Conventional Polytunnels 16'6", 18' and 22' wide:  38.01mm (1 1/2") diameter tube.

- Conventional Polytunnels 24' wide:  50.80mm (2") diameter tube.

- Space Saver Polytunnels up to and including 16' wide:  31.75mm (1 1/4") diameter tube.

- 18' wide and wider Space Saver models up to 27' width:  50.80mm (2") diameter tube.

- Cloche hoop frames:  25.4mm (1") diameter tube.