Underwater yacht light mounting options

How underwater lights will be mounted is an incredibly important decision and needs careful consideration. There are three underwater light mounting options: thru-hull, electromagnetic induction and surface mounted, however another option may be lighting installed on the transom.

Inductive Technology

Thru-hull lights

Thru-hull underwater lighting units will require a drilled hole through the hull of a yacht to pass wires and the actual light unit through.

Advantages of through-hull lighting:

  • Easy to replace a burnt-out bulb
  • Interchangeable. This means the light array can be serviced (removed and replaced) from inside the hull with the boat in the water
  • Generally brighter as larger light units can be used

Disadvantages of through-hull lighting:

  • Drilling through the hull will be needed
  • More expensive than surface mounted lighting

Interior access can prove to be an issue

Induction lighting

Induction operates by having the primary unit (the housing for all the inverter electronics and communication control) on the inside of the yacht, lined up with the secondary unit (the luminaires and drive circuitry) on the exterior of the yacht. Both units are positioned in place by marine grade adhesive. 

Advantages of induction mounting:

  • No drilling whatsoever
  • Similar water penetration to thru-hull models
  • Can be accessed from the inside of the boat

Disadvantages of induction mounting:

  • More expensive than surface mounted lighting
  • New technology, which means it is untested in general use

One lighting specialist embracing this new technology is BGB SILS. Its marketing manager, James Tupper explained, “Perfecting the induction technology and in particular the moulding of the material for the yacht lights has taken up the vast majority of R&D time.

“It certainly hasn’t been easy but we‘re close to having productionised units ready for real-life testing.  We have enquiries on a daily basis through the website and certainly receive lots of attention at the shows we exhibit at. 

“Our potential customers and test boats have been really patient with us and fully understand that a unique product like SILS needs to be perfected before we dare release it to an industry that seems to be crying out for induction LED products.”

Surface-mounted lights

These types of lights only require a small hole to accommodate a wire and some state of the art units need no drilling at all.

Advantages of surface-mounted lighting

  • Cheaper than the thru-hull models
  • No drilling necessary

 Disadvantages of surface-mounted lighting

  • Surface-mounted lights last only for the light lifetime, so once its dead, you need to change the whole unit
  • They generally use smaller systems so not as bright as thru-hull systems
  • Difficult to replace/repair

Controlling BGB

Beam width/spread angle

Another major influence on the amount of light that’s produced is the width and angle of the light fitting.

Spread angle

It’s important to check the penetration angle, the higher the angle generally the more expensive, for example most LED's start at 40 degrees (0 starting horizontally then going down), this will effect the spread of the light backwards and downwards, again, the more the spread is, the higher the price is. 

Beam width

The beam angle of the underwater light determines how the light beam appears around the hull. Available in narrow spot (less than 90°) or wide flood (greater than 90°), it produces an even glow of light and allows lights to be spaced further apart on the hull.

Questions to ask when buying underwater lights

When buying any underwater light there are several questions you need to ask to see which is most suited to your boat:

  • What is the beam power in angle degrees and lumens?
  • How much power does it need?
  • Do you have easy access to your hull?
  • Will the light fitting fit through your hull?
  • What is the life span of the unit?
  • Is it in your budget?

For more information, tips and advice on yacht lighting, visit our guide page. Or search lights and lighting consultants here.


Lights & Lighting Consultants Articles
March 12, 2021
Tried & Tested: Best Yacht Crew Polo Shirts
Tried & Tested: Best Yacht Crew Polo Shirts

In this Tried & Tested, clothing specialist Sea Design conducts a review into the best yacht crew polo shirts on the market. Which garment comes out on top when put to the test? Find out the number one option...

By Nathan Bees
January 21, 2021
Tried & Tested: Best Yacht Cleaning Products
Tried & Tested: Best Yacht Cleaning Products

In this Tried & Tested, yacht cleaning expert Marine 16 Ltd and cleaning expert Judith Shaw rate and review some of the best cleaning products available to buy. Find out which product was crowned the best following rigorous testing.

By Yachting Pages
January 13, 2021
Tried & Tested: Best Water Toys
Tried & Tested: Best Water Toys

In our brand new Tried & Tested, yacht water toy specialist EAMS and a group of experienced superyacht captains and crew rate and review the very best luxury water toys on the market. Find out which brand and product was crowned the best...

By Nathan Bees
Thailand’s ‘Test & Go’ could reopen by 1st February 2022

International yachts and superyachts could soon see Phuket return as a preferred destination following the announcement ...

By Holly Sanderson
January 21, 2022
Thailand’s ‘Test & Go’ could reopen by 1st February 2022
Porto Montenegro reaches new stage in shipyard development

Porto Montenegro has continued to build a strong foundation for the future by developing the former Bijela Shipyard as a...

By Annabelle Fox
January 21, 2022
Porto Montenegro reaches new stage in shipyard development

Finished reading? Now find your perfect supplier.

Search our industry-leading directory for over 20,000 superyacht suppliers, providers and marinas.

Search now