direction plates will need to be fitted to the air inlets. These will direct the incoming air below the obstruction
but still to the apex of the roof. The direction plates must be carefully and correctly set. A presentation type
laser pointer can be used to help determine if the direction plate is set correctly. By holding the pointer on
the air direction plate and seeing where the laser dot hits the roof surface, it can give a good idea of the
angle at which the direction plate should be set in order to avoid the obstructions (Figure 35).