CIBSE LG7 / BS EN 12464
50–70% on lighting load
Usually 2–4 years
5 years on most fittings
Mon–Fri 8am–5pm. 24/7 emergency line out of hours.
Lighting is usually the largest single electrical load in a commercial building and the one most likely to be twenty years out of date. Replacing fluorescent and halogen with LED typically removes half to two-thirds of that load, and removes the lamp-changing visits with it.
The saving is only part of it. Lux levels, glare and colour rendering determine whether a space is comfortable to work, learn, treat patients or sell in — and old installations are frequently both wasteful and badly lit at the same time.
We survey the existing installation, measure actual lux levels against the CIBSE recommendation for each task, and design a replacement scheme rather than swapping fitting for fitting. In practice that often means fewer luminaires, better placed, with better distribution.
Controls are where the remaining savings sit. Presence detection in intermittently occupied spaces, daylight dimming near glazing, and time scheduling on external and circulation lighting routinely take another quarter off consumption without anyone noticing a change.
Every proposal is modelled: existing load and hours, proposed load and hours, expected saving and simple payback. If the numbers do not work on a particular area we will say so rather than including it to inflate the project.
Existing fittings, wattages, hours of use and measured lux levels recorded per area.
Layout designed to CIBSE recommendations for each task, not simply matched to existing positions.
Commercial-grade luminaires with warranties, installed and tested by our own electricians.
Detection and dimming in stores, corridors, toilets, offices and perimeter zones.
Emergency luminaires integrated into the new scheme and brought onto the test regime.
Before and after load, projected saving and simple payback, in writing.
Existing installation recorded and lux levels measured against task requirements.
Scheme layout, control strategy and an energy model with projected payback.
On larger schemes we light one area first so you can see it before committing.
Phased installation, controls commissioned and set up, old fittings removed and recycled.
Savings are against the same LED fitting without controls — they stack on top of the LED saving itself.
Sometimes, and it is the cheapest option. But retrofit tubes in old fittings keep the old optics and old positions, so you get the energy saving without the lighting improvement — and warranties are shorter.
Low. It is usually done area by area outside occupied hours, with each area finished and working before we move on.
Yes. Areas with very low hours of use rarely justify replacement on energy grounds alone, and we will flag those as maintenance-driven rather than savings-driven.
Only if they are set up badly — detection that times out too fast is the usual complaint. We commission on site and revisit settings after a few weeks of real use.
A survey will tell you the saving, the payback and what the space would actually look like.
