Showing the Zincalum angle used to seal the gap beside the Cast-iron "V" groove track wheels. The external green plates are the "anti-lift brackets" to stop lifting in high winds. We have already had one severe storm with high winds but as this came from the North along the roof it did not give any real lift. The ends of the 75 x 50mm roof trusses have been capped to stop birds and mud-hornets building there.