96
Architect’s Pocket Book
Imposed roof loads Distributed load kN/m2
Concentrated load kN
Roof type
Comments
Flat roofs and sloping roofs up to 10°
Where access is needed in addition to that needed for cleaning and repair
1.5
or
1.8*
Flat roofs and sloping roofs up to 30°
Where no access is needed except for cleaning and repair
0.6
or
0.9*
Roof slopes between 0° and 60° measured on plan
Where no access is needed except for cleaning and repair
0.6
or
0.9*
Roof slopes 60° or more
0
0
* Whichever produces the greater stress.
Where access is needed for cleaning and repair, these loads assume spreader boards will be used during work on fragile roofs. For buildings in areas of high snowfall, snow loading should be taken into consideration. The superimposed load would normally be increased to 1 kN/m2 except for certain highland areas in Scotland where it might be increased to 1.25 kN/m2