|
|
see para 1.2b
The following: are examples of provisions for background
ventilation. In each case, the ventilation opening should
be located (typically 1 .75m above floor level) so as
to avoid discomfort due to cold draughts.
|
|
3. Vertical sliding sash windows with adjustable
fixed locking positions
 |
| 1. Trickle ventilators |
|
 |
|
| _ a) In
window frames |
|
 |
|
| _b) In glazed
openings |
|
For background ventilation, the opening of the window
should be adjustable to provide the required area and
lockable so it is secure when open for background ventilation.
Note: Provisions in B1 for certain windows
to be usable for means of escape.
4. High-level top-hung window with adjustable locking
positions (because of the risk to security, this
should generally be restricted to use above ground floor
level)
|
 |
|
|
_c) Above window frames
2. Airbrick with “hit and miss” ventilator
|
|
 |
 |
|
|
Notes to examples 1 and 2:
To minimise resistance to air flow, the main air passages
(not insect screens or baffles, etc.) of an installed
ventilation opening (when fully open) should have a
smallest dimension of at least 5mm for slots or 8mm
for square or circular holes.
|
|
For background ventilation,
the opening of the window should be adjustable to provide
the required area and be lockable with a removable key
or similar device so it is secure in at least two opening
positions for background ventilation. |
xx
