- Location
- Caernarfon, Gwynedd
- Main postcode district
- LL55
- Nearby (straight line)
- Llangefni (8 miles), Bangor (9 miles) and Holyhead (19 miles)
- Survey and quote
- Free, with a fixed written quote
Dock traffic lights are red and green signals mounted outside and inside a loading bay to tell the driver and dock staff when it is safe to move or load. Interlocks are control links that stop equipment operating out of sequence, for example preventing the door opening until the trailer is restrained, or the leveller operating until the door is fully open.
Where does this fit at a dock in Caernarfon?
Sites around Caernarfon that run night shifts often find traffic lights easier for drivers to read than staff waving or knocking on the cab door. Distribution centres near Caernarfon taking trailers from many different hauliers benefit from a signal every driver understands, regardless of language or familiarity with the site.
Whether your unit in Caernarfon has one dock or twenty, the survey looks at each bay's existing controls before we quote a fixed price in writing.
A single contact at Loading Bay Doors handles your project in Caernarfon from start to finish. The free site survey and fixed written quote come first, with no obligation to proceed. We then book the installation for times that suit the operation, including out of hours by arrangement, and manage the specialist engineers on site. At the end we commission and test the equipment, walk your team through it and provide the documentation.
How much do dock traffic lights and interlocks cost?
Dock traffic lights and interlocks typically cost £650 to £3,400 per bay, supplied and fitted, excluding VAT. A pair of manually switched LED signals sits at the lower end, while a full interlock panel linking door, leveller, restraint and shelter sits towards the top.
What moves the price:
- Level of control: standalone lights, door-linked lights or a full interlocked sequence.
- Existing control panels: modern door and leveller panels often accept interlocks directly; older panels may need replacing with a combined bay panel.
- Sensors: door position switches, trailer presence sensors and restraint signals each add parts and wiring.
- Cable runs: distances between lights, panels and the power supply.
- Number of bays and timing: repeat bays reduce the cost per bay, while out-of-hours working adds to it.
These are guide budgets. After a free site survey we send a written quote, and that quote is the fixed price. VAT is added at the standard rate.
How do inside and outside dock traffic lights work together?
Inside and outside dock lights always show opposite colours: when the driver sees red, dock staff see green, and the other way round. Each light is aimed at a different person, so each one only ever gives one instruction.
- Outside light, facing the driver: red means stay on the bay because loading is in progress; green means the bay is clear to leave or to reverse on to.
- Inside light, facing dock staff: green means the trailer is in place and it is safe to open the door and load; red means do not open the door or enter the trailer.
Lights can be switched in three main ways:
- Manually, by a switch beside the door, relying on dock staff to change it at the right moment.
- By door position, so opening the door automatically turns the outside light red.
- By the restraint, so the light only changes when the trailer is physically held.
The same published guide range applies across Wales; access, out-of-hours working and site conditions are confirmed at the free survey.
Survey checklist for your dock
- Power supply at each bay, including three-phase availability
- Control positions, isolators and any existing interlocks
- Wind exposure at the dock, which affects door and shelter choice
- Headroom above the opening and which track type will suit it
- How often each door cycles during a typical shift
- Working hours, shift patterns and windows for out-of-hours work
Options to discuss
Restraint interlock package
Door, lights and vehicle restraint tied together so the door only opens once the trailer is held and the restraint only releases when loading is finished.
Standalone LED traffic lights
A red and green pair for each bay, one outside for the driver and one inside for dock staff, switched manually from a control beside the door.
Regulations and approvals in Wales
Equipment fitted in Wales may carry the UKCA or the CE mark. For each door, leveller or shelter installed in Caernarfon, we hand over the documentation that comes with it. Permissions are never assumed either way: whether planning permission or Building Regulations approval is needed, we check what applies at survey and tell you before dates are agreed.
Questions about dock traffic lights and interlocks in Caernarfon
How long does installation take at a site in Caernarfon?
It depends on the equipment, the number of bays, the condition of the dock and whether any building or electrical work is needed. We agree a programme with you after the survey, setting out which bays are out of use and when. Larger jobs are usually phased so that part of the dock stays open, and out-of-hours working can be arranged.
What details do you need from us to quote for dock traffic lights and interlocks?
To get started, send the site address in Caernarfon, the number of bays or openings, approximate sizes, and photos of the dock from inside and outside. Tell us what vehicles you load, what goods you handle and any temperature requirements. Drawings help on new builds. We then arrange the free survey and confirm the details before the written quote is issued.
Do you cover Caernarfon for dock traffic lights and interlocks?
Yes. We take on dock traffic lights and interlocks for businesses in Caernarfon and across Gwynedd. We survey the site, provide a fixed written quote and manage the installation, with specialist installation engineers working under our management. Visits are arranged in advance at a time that suits your operation, and the same single contact stays with the job through to handover.
Do traffic lights and interlocks need maintenance?
Yes. Lights, sensors and interlocks should be checked at each planned service visit, including testing the full sequence and confirming that steps attempted out of order are blocked. As part of the dock equipment they fall under PUWER, which requires work equipment to be maintained in a safe condition.
Will interlocks slow down my loading operation?
Interlocks add a fixed sequence, but each step takes only moments and staff soon get used to it. In practice many sites find the sequence saves time overall, because there are fewer arguments about when to open the door and less damage from levellers being raised into part-open doors.
Dock traffic lights and interlocks near Caernarfon
We also cover towns near Caernarfon, including Llangefni (8 miles), Bangor (9 miles) and Holyhead (19 miles). Each has its own page with the same services and process.
Other loading bay services in Caernarfon
Full guide to dock traffic lights and interlocks · Everything we do in Caernarfon
For a written price on loading bay work in Caernarfon, request a quote and include photos of the bay if you can.