A curtainside truck or trailer has canvas curtains on rails down the side that can be drawn back to allow easy loading and unloading by a forklift from either side. Behind the curtains is a flat deck truck. The roof is held up by side rails and there is a rigid rear (which can also contain doors) and a rigid headboard.
Curtainsiders can also have a chiller unit. These tend to have thicker curtains to keep the cold air in.
The curtain is held tight with buckles. The driver can undo the whole curtain or simply a section of the front or back. The buckles pull the curtain tight downwards to stop it flapping in the wind.
A ratchet pulls the curtain tight horizontally.
Curtainsiders are ideal for freight that can be loaded and unloaded by a forklift operator. Most commonly this is palletised goods, but flexible bulk bags and other products can be loaded.
Some curtainsiders also have a top curtain and can be used to carry loads which are dumped from a silo or loaded via a front-end loader, such as wood chips.
Curtains are rated to a certain level of load restraint in kilograms per metre, and this can be found on a plate attached to the curtain itself. This load rating is valid when goods are loaded within 100mm of the curtain. For more information about load security and how to load with curtains, this load security course has a specific module on curtainsiders.
What are the problems with curtainsiders?
As long as the load is unlikely to fall and it’s positioned within 100mm of the curtains, there’s no requirement for the load to be restrained by anything other than the curtains (assuming they are rated). However, freight does frequently move and it can tip over, causing the curtain to bulge. A bulging curtain will sometimes put a truck over its maximum road width of 2.55m. It’s always safer to restrain the freight within the curtainsider, and for that, you’ll need enough ratchet strops.
Unrestrained loads also create a danger when the curtains are opened that the load might fall on someone. If this has happened, open the load compartment from the other side to investigate.
Opening the curtains in strong winds can be dangerous. ACC reports accidents involving back injuries through twisting when pulling the curtain and injuries to hands from getting them trapped in the rail or the ratchet. It’s easy to trip if walking backwards with the curtain.
Curtains are not as insulated as a box body for chilled freight.
Curtains can be cut and damaged easily, plus there’s no way of securing them (the buckles can simply be opened by anyone so they’re not good to leave in insecure areas.)