Woodworm solution for England’s largest surviving Medieval gateway


Client: Canterbury City Council

Products Used: Insecticide/Fungicide Spray

Built-in 1380 Westgate Towers is England’s largest surviving Medieval Gateway. The Towers is a scheduled ancient monument and Grade I listed building, where tourists and history enthusiasts can explore its rich history and take in the spectacular views of the city from the battlements viewpoint.

The Westgate Towers Built of Kentish ragstone approximately 60 foot (18m) high and is the largest surviving city gate in England and one of Canterbury’s iconic landmarks.

As part of a large scale restoration of One Pound Lane that took place between 2015-2018, Timberwise were recently instructed by Canterbury City Council to provide a timber and damp survey for the regions historic Westgate Towers, an iconic medieval landmark ascending above the beautiful town of Canterbury.

Our instructions were to inspect the timbers within the property for wood rot and infestation by a wood-boring insect.  From our inspection, our surveyors found a number of  types of infestation, including:

  • Common Furniture Beetle (Anobium punctatum)
  • Wood Boring Weevil (Euophryum confine)
  • Wet Rot Fungus (Fibroporia vaillantii)
  • Death Watch Beetle (Xestobium rufovillosum)

Did you know?

The Canterbury trot was the name given to the way pilgrims rode their horses to get to the city before the night-time curfew.  

Port Cullis

The portcullis is a strong, heavy grating that can be lowered down grooves on each side of a gateway to block it. Upon arrival, Timberwise carried out a timber inspection to the large spanning lintel to the portcullis within the Guard Chamber and the upper floor timbers within the North Tower. Timberwise noted there was considerable evidence of moisture ingress, as well as surface signs of decay and mycelium.

Another day, another stunning location. What a pleasure it will be for myself and our team of technicians to do what we do best, for such a historical landmark ”

Woodworm Specialist

North Tower

The inspection revealed an old and inactive infestation with re-infestations of wood borer activity; flight holes of recent origin were also observed denoting larval activity.

The right-hand window lintel had decayed to a structurally unsound condition and would require replacement. The direct cause of the fungal decay was due to timbers been built directly into the masonry with no protection against moisture absorption. We advised that all new timbers must be isolated from the masonry with a suitable membrane.


Dry rot is often underrated and misunderstood and you can never be too cautious in dealing with an outbreak. All affected timber must be removed, brickwork sterilised and any new timber installed within a previous dry rot affected area must be both treated and isolated from contact with any previous area of outbreak.

To eradicate the fungal decay and mycelium Timberwise applied a dual purpose insecticide/fungicide surface coarse spray; this would enable the fluid to penetrate the areas that cannot be accessible by brush. In addition, this fluid would have no effect on the external colouration or blooming, therefore leaving the timber in its original state.

This treatment is also to be complemented with the injection of fungicidal paste to the ends of the lintel that was in contact with the masonry. The slow acting rods will give deep-rooted treatment and prevent further decay.

Need help with your property care problem?

If you have any questions about woodworm in your property and feel you may need us to carry out a woodworm survey, please feel free to chat directly to one of our property care team. Simply request a property survey online or click on the ‘let’s chat’ button to chat to Timberwise and we’ll help you with your property care problem. Alternatively, give us a call on 0800 288 8660.

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