Guide
Illuminated shop signs: lighting methods, wiring and consent limits
Updated
Lighting a sign roughly doubles the number of things that can go wrong and adds a second trade to the job. It is usually worth it, and it is always worth pricing properly.
The four ways a shop sign gets lit
- Halo illumination
- LEDs behind built-up letters throw light onto the fascia, so the letter reads as a silhouette against a glow. The most expensive-looking option and generally the best received on sensitive frontages, because the light source is not visible. It is also explicitly named as a permitted illumination method in the deemed consent classes.
- Face lit letters
- Light comes through an acrylic letter face. Bright, legible at distance, and the deemed consent classes allow internal illumination of each character or symbol so long as no part of the background is illuminated.
- Illuminated tray or lightbox
- A fabricated box with a translucent face, lit from within. The traditional bright fascia sign. Note that the deemed consent classes cap the depth of a built-up box containing the light source at 0.25 m, and a fully illuminated background takes you outside the internal illumination allowance.
- External trough or spot lighting
- Lamps mounted above or below throw light onto a non-illuminated sign. Cheapest to install, easiest to maintain, and frequently the answer on listed and conservation area frontages because the sign itself stays unlit and traditional.
The illumination rules deemed consent imposes
If you want an illuminated sign to sit inside deemed consent under Class 4B, illumination is permitted only where it is by static means, and where it 'includes no intermittent light source, flashing lights, moving parts or features, exposed cold cathode tubing, animation or retroflective material', and is in a manner reasonably required to fulfil the sign's purpose (Schedule 3).
- No flashing, no animation, no moving message. Anything dynamic is outside deemed consent and needs express consent.
- Halo, or lit characters on an unlit background. Those are the two internal illumination routes the class allows.
- A luminance cap applies to signs lit by internally illuminated characters, set out in Part 2 of the Schedule. A sign maker specifying a very bright face on a large sign should be able to speak to it.
- And in a conservation area, none of this helps, because Class 4B gives no deemed consent there at all. That is an express consent application, whatever the lighting method. See the consent guide.
The electrical work nobody quotes for
- Is there a supply at the fascia already? If not, someone is running a circuit from the consumer unit through the shop, and that is disruption as well as cost.
- Isolator and switching. A local isolator is standard practice and sometimes required by the landlord or insurer.
- Certification. Electrical work should be carried out and certified by a competent person. Ask whether the certificate is included, because your landlord and insurer may ask for it.
- Timer or photocell. Cheap to add, and it decides how much the sign costs to run over ten years.
- Access for the electrician, which may mean the same tower or platform twice unless the trades are coordinated.
Running and maintenance cost
Modern LED signage uses very little power, so the running cost is rarely the issue. The maintenance cost is. A failed LED module or driver is a small part and a large access charge, because somebody has to get to the sign. That is why the maintenance question belongs in the quote comparison:
- How is the sign accessed for repair? A removable face is a different maintenance proposition from a sealed fabrication.
- What is the warranty on the LEDs and the driver, and does it include labour and access or only the part?
- Are the components standard? Proprietary modules from a supplier who may not exist in five years are a risk you can price.
- Is the sign sealed to the right rating for an external location? Water ingress is the other half of why illuminated signs fail.
- What does a callout cost once the warranty has run out?
Get the illuminated and non-illuminated versions of your design priced together. On a sensitive frontage the externally lit version is often both cheaper and easier to consent, and on a busy road the illuminated version earns its cost back in visibility. Ask for both.