General preparation and installation advice
In service the entire load on a unit is transferred to the frame and thus to the structural opening.
It is vital that the structure of the opening itself is adequate and that the bedding to be applied beneath the frame is sufficiently strong.
A frame which is not correctly supported may distort in service leading to a failure of properties and ultimately to the unit becoming unstable.
A twisted frame is incapable of giving proper support to the cover as it will be subjected to forces for which it was not designed.
If the cover/ grating has been separated from the frame, ensure any debris is removed from the frame before re -assembly
If not, ensure that any debris is removed from the complete unit prior to installation.
Check and re-fit any locking down screws ensuring they are clean and lightly greased.
Ensure that any keyholes, locking bolts, watering points, drainage slots etc are protected.
Centralise the unit over the chamber / tree pit – not just in the rebate.
Loosely position frame holding down bolts or mark for drilling of anchor bolts.
Set frame to required level with mineral or metallic packing and adjust as necessary with holding down bolts still loose.
Check level and, if necessary, align with finished floor level by adjusting packing.
Run grout or bedding compound if specified, under entire frame.
When grout is fully hardened check that the gratings can be removed freely before laying screed / paving.
When screeding / paving ensure that the locking bolt holes, watering points, drainage slots etc are again protected from the sand / cement.
NOTE: FAILURE TO CARRY OUT THE ABOVE INSTRUCTIONS WILL AFFECT THE PERFORMANCE OF THE GRATINGS AND FRAMES