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Room Minimum intermittent extract rate Continuous extract  
  Minimum high rate Minimum low rate
Kitchen 30 l/s (adjacent to hob); or 60 l/s (elsewhere) 20 l/s Total extract rate must be at least the whole building ventilation rate in Table 2
Utility room 30 l/s 8 l/s  
Bathroom 15 l/s 8 l/s  
Sanitary accommodation 6 l/s   
 Number of bedrooms in dwelling     
 12345
Whole building ventilation ratea (l/s) 1317212529
 Minimum value in any dwelling of 0.3 l/s per m2 internal floor area b
a) This is based on two occupants in the main bedroom and a single occupant in all other bedrooms. For greater level of occupancy add 4 l/s per occupant.
b) This includes each floor e.g. for a two storey building, add the ground and first floor areas.
*Note: this article was prepared by reference to the most recently available draft of AD F released by the ODPM last year.