low energy lighting
is a major component of electrical energy use in
tower blocks as the lights in communal areas
remain switched on through out the night. Majority of un-refurbished
tower blocks use incandescent light bulbs [tungsten] or
older fluorescent tubes [T12] with magnetic chokes to light
the common areas. Replacing these fittings with energy efficient
lighting can save up to 30-50% of the energy bills.
lamps and ballast [control gear], must at least have a luminous
efficacy of 40 lumens/circuit-watt [see graph].
As a rule of thumb, Compact
Fluorescent Lamps [CFLs] and T5 fluorescent
tubes with electronic ballast are most suitable for lighting
the communal areas.
Outdoor/ security lighting
suitable for external use, especially where lighting is
required through the night. High-pressure discharge
lights could also be considered where high lighting output
conventional incandescent lights may be more suitable in
areas where frequent switching may occur.
Case study: Jackson House, London Borough of
The lighting in the tower block's communal
areas, which had tungsten lamps, were changed to CFLs.
Energy consumption was monitored before and after
the lamp replacement programme. The mean electricity
reduction was found to be 27%. The payback period
was found to be less that 1 year.
[Source: Good Practice
Case Study 86, BRESCU]
Corridors require good,
uniform lighting so that residents can find their way quickly
and efficiently. Effort must be taken to prevent "tunnel
effects" in extended corridors.
Illuminated walls make a corridor
look wider; indirect light bounced off the ceiling makes
it look more open and welcoming.
In long corridors, it is also
recommended that luminaires should be set at right angles
to the direction of movement to make the corridor appear
Staircases: People are more prone to accidents on
the stairs therefore, care must be taken to
ensure that they are uniformly illuminated. An ideal
location for luminaires is the under side of the landing.
This ensures that each tread is clearly seen. Staircase
lighting calls for luminaires designed for wide-angled intensity
distribution: adequate numbers of wall or ceiling luminaires
mounted parallel to the stairs.
For the first three storeys
of the tower block orientation lights may be provided, which
can be either recess- or surface-mounted on walls or
set into the risers of stairs. Staircases are also escape
routes. Escape route marking and lighting must be installed
and maintained in line with the relevant standards.
Lifts: Many people
feel uneasy when they enter a lift. Enclosed lifts can fuel
claustrophobia, glass lifts in high halls trigger fear of
heights. Lighting at lift access points should therefore
be reassuring, which is achieved by providing significantly
higher illuminance, boosted, for example, by wall luminaires
on the right and left of the lift doors. This makes for
a greater sense of security.
Inside lifts, surfaces should basically be light-coloured.
Mirrors and gloss-finish walls and ceilings not only promote
an agreeable ambience; they also make the lift seem bigger.
Lighting with a strong diffuse component prevents deep sharp-edged
shadows on the face of other lift users. [Source:
Fordergemeinschaft Gute Light]
CIBSE Guide recommends an
average lighting level between 100 to 150lux for
stairs, landings and
Fittings for outdoor lighting
should be selected so that they do not directed light onto
the sky. Not only is this wasteful in energy terms it also
‘pollutes’ the view of the sky.