The local council aids and alterations technicians department have this information and will share it with you if you ask. Try going through Occupational Therapy. Can I ask which is your local council and I may be able to find it for you.
The property is an elevated bungalow with high steps at the front so the best
access is the back gate which is also at the front ..so hence the path has to be wider then sloped to be safe ....OT are not very good here as they are under staffed .....but I will call the council tomorrow , but I think a metre would be about right . Thanks for replys .
pitch should be around 1 foot of length for 1 inch of drop or rise. You manage the issue of needing a long ramp by zig zagging the path with level "landings" at each turn. make sure that the surface is roughened or ridged as losing control of the chair in slippery conditions is no fun.