The Government’s £4.4 billion Priority School Building Programme is well underway and by the end of 2021 a total of 537 schools will have been rebuilt or refurbished.
When designing the lighting scheme for a new or refurbed school, there are many things to consider including time constraints, regulations, energy-efficiency and special client requirements. The development of new technologies, and the vast array of products on offer mean it can be hard to decide on the best system for the job. Laid out below are just a few of the things worth thinking about before making your choice.
Regulations and guidelines
EFA (Education Funding Agency) guidelines for lighting in schools emphasise the importance of energy-saving. According to the Carbon Trust, lighting accounts for 20-25% of the total energy used in schools. Significant savings can be made by switching to energy efficient lighting equipment. As well as reducing the carbon footprint of a school, college or university, these measures have the added benefit of reducing running costs of a lighting application. Occupancy sensors alone, can reduce lighting costs by as much as 30%.
Although not compulsory, LSHF cable is now recommended for use in all public buildings such as schools and universities due to the safety implications of PVC or LSF cable use, in the event of a fire. LSHF, is manufactured to BS EN 50525-3-11, and meets strict requirements. When burnt it produces small amounts of light grey smoke, and miniscule amount of HCI. Part B, Section B1.iv of the current edition of The Building Regulations state:
“The primary danger associated with fire in its early stages is not flame but the smoke and noxious gases produced by the fire. They cause most of the casualties and may also obscure the way to escape routes and exits. Measures designed to provide safe means of escape must therefore provide appropriate arrangements to limit the rapid spread of smoke and fumes.”
To be sure that you know what you’re getting when you ask for LSHF cable, insist that it is BS EN 50525-3-11 compliant.
As the well-known adage so succinctly states; ‘Time is money’. It’s always a challenge to keep a construction project on schedule, so any products that offer simple and rapid installation should be a welcome option. A traditional hard-wired installation involves manually wiring each luminaire in a room to a central junction box which can be extremely time and labour intensive. An ever more popular choice now is to use a prefabricated lighting connection and control system, because it can save significant installation time on site. Modular systems like this are pre-wired by the manufacturer, then simply plugged-together on site. Using a prefabricated system rather than traditional hard wiring can reduce installation time on site by up to 50%. This also leads to reduced requirement for skilled labour. Cable snagging, and wastage are also cut down.
Using a modular plug-together system makes it relatively easy to update or replace areas of your lighting installation without disrupting everyday use of the building. If the lighting connection system is tested to BS5733 it means that onload connection and disconnection is possible.
Choosing lighting controls with an integrated emergency test facility can save both time and money on an installation. When using a lighting control device with integrated emergency test the need to wire back to the switch separately is negated, as the wiring is contained within the control device, and switch drop lead. If the lighting controls can be networked then a single key switch can test emergency luminaires across multiple circuits or phases. When using a system that operates at protected extra low voltage, the voltage at the test switch will operate at below 50V. This avoids scenarios where multiple key switches are grouped in a centralised, multi-gang enclosure with the potential for 415V to be present, which requires extra labelling as per regulation 514.10.1 of BS 7671.
Daylight linking lighting controls
Government guidelines for lighting in schools state that ‘natural lighting during daylight hours should always be the major source (of light), supplemented when it fades by electric light which will take over during hours of darkness.’ There are two options for achieving this; daylight dependent controls and daylight dimming controls. Daylight dependent controls are the more basic of the two options, and will turn lights off when there is sufficient natural light in a room, and on again when needed. Daylight dimming controls will adjust luminaire output in response to daylight, dimming them up or down to maintain a constant light level in the room.
Classrooms follow a fairly standard lighting layout. A separate switch for lights in front of whiteboard or projector is often required, and daylight linking controls along window rows. There are often small cupboards, or offices next door to classrooms which can share power, but require separate control options. In response to this there are now a number of products on the market that provide a plug-in lighting connection solution with integrated, pre-programmed lighting control configurations common to teaching environments.
With the addition of a wall-mounted scene setting plate it is possible to select different configurations which can easily be recalled at the press of a button. The kind of options available in a product like this include absence/presence/daylight linking/graduated daylight dimming lighting control, independent switching of whiteboard or projector lights, emergency test, corridor hold and last man out switch.
Schools are by design comprised of a high number of corridors and stairwells. In buildings in which lighting controls are installed, it is often expected for safety or security that such areas be lit whenever a room adjacent to them is occupied. A solution to this is using a product that can provide a ‘corridor hold’ function, such as the flex7 Corridor Hold Unit. Up to 8 separate lighting control devices can be plugged into the unit, and as long as one of these is holding lights on in an adjacent room, the corridor or stairwell connected to it will also remain lit.
Where lighting controls are used, installation costs can often be accompanied by a hefty commissioning cost prior to handover of the building. These costs are often not included in the price on a project quotation, and typically equate to upward of £500/day. It’s worth considering these costs, which vary from manufacturer to manufacturer when looking at lighting control options.
Whatever the scale or complexity of your installation it’s worth keeping an eye on the latest technology. The nature of the industry means that developments are constantly being made, and ever more complicated scenarios are being catered for. Whatever your lighting connection or control requirement, there’ll be a company somewhere who can provide exactly what you’re looking for.
If you’d like some help or advice on using flex7 lighting connection and control products in your school or unviersity project give us a ring on 020 8580 1066, or alternatively click on the button below for more online information: