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BEAM PLUS FOR NEW B UILDINGS INDOOR ENVIRONMENTAL QUALITY (IEQ)
V ERSION 1.2 IEQ 11 L OCALISED V ENTILATION
Copyright © 2012 BEAM Society Limited. All rights reserved.
Page 163
DOMESTIC KITCHENS PNAP No. APP-130 [1] specifies performance based criteria for kitchen
ventilation as an alternative means of satisfying Building (Planning)
Regulations (B(P)Reg.) 30, 31 and 32. These criteria are 1.5 ACH under
natural ventilation, plus 5 ACH from mechanical means i.e. these values
are by definition the minimum legal requirement. Whilst these are
performance based alternatives to the prescriptive criteria they are
considered worthy of credit. It should be noted that specifying higher
values may result in negatively pressurizing the building and causing
other IAQ problems with in flow of air from other spaces.
Elsewhere, ASHRAE 62.2 [2] states that kitchen fans are mandatory as
this standard considers that windows do not provide sufficient ventilation,
although this standard specifically applies to low rise residential units (3
storeys or less above grade) and wind conditions may not be as
favourable for ventilation as in the case of high rise buildings. The basic
requirement is that a vented cooker hood can exhaust 100 cfm (approx
50 l/s). An alternative approach is that ventilation (either continuous or
intermittent) of 5 ACH be achieved.
COMMERCIAL KITCHENS In commercial kitchens a mechanical ventilation rate of 20 ACH may be
appropriate [3] for the cooking styles found in Hong Kong.
BATHROOMS AND
TOILETS
The Building Authority will give favourable consideration to an application
for modification of Building (Planning) Regulation 36 in respect of
bathrooms and lavatories in domestic buildings [4] where the following
criteria are met :
 the room is part of a unit of accommodation for domestic use;
 the room is of a reasonable size; and
 the modification to be granted is unlikely to result in standards of
public health and safety being compromised.
Upon the grant of a modification of the Regulation, the Building Authority
will impose the following conditions:
 mechanical ventilation producing 5 air changes per hour (ACH) is in
operation at any time when the room is in use. The change of air
shall be with the outside of the building and to achieve this, the use
of ventilation ducting is acceptable;
 there is permanent ventilation to the ‘open air’, the ‘external air’ or
with another room which is provided with a window meeting the area
requirement for the combined windows. The permanent ventilation
may be in form of an air duct, an aperture in a wall or a door suitably
located and permanently open or protected with louvers having a
minimum size of 1/20 of the floor area of the room; and
 the requirements of Building (Planning) Regulation 35A and PNAP
No. APP-27 [5] regarding water heaters are complied with, where
applicable.
1 Buildings Department. Practice Note for Authorized Persons, Registered Structural Engineers and Registered
Geotechnical Engineers, PNAP No. APP-130. Lighting and Ventilation Requirements - Performance Based Approach.
2 ASHRAE 62.2-2003. Ventilation and Acceptable Indoor Air Quality in Low Rise Residential Buildings. American Society of
Heating, Refrigerating and Air Conditioning Engineers. Atlanta. 2003.
3 Singapore Standard SS CP13. Code of Practice for Mechanical Ventilation and Air Conditioning in Buildings. 1999.
4 Buildings Department. Practice Note for Authorized Persons, Registered Structural Engineers and Registred Geotechnical
Engineer PNAP No. APP-98. Lighting and Ventilation for Bathrooms and Lavatories in Domestic Buildings.
5 Buildings Department. Practice Note for Authorized Persons, Registered Structural Engineers and Registered
Geotechnical Engineers, PNAP No. APP-27. Gas Water Heaters - Building (Planning) Regulation 35A.