Gull problems on Allen Construction Consultancy site roof

Tackling a historic gull problem for Allen Construction Consultancy

Allen Construction Consultancy is a specialist property and construction consultancies who were employed by Buildbase to carry out roof repairs. The site had a historic problem with gulls nesting on the roof and for Allen Construction Consultancy to be able to carry out their works the gull problem had to be solved.

The gulls had damaged the roof with their acidic fouling and their nesting debris blocking the drains which led to the roof to leaking. Gulls also picked at sealant around the skylight which caused water ingress into the building. In addition the aggressive behaviour of the gulls during the nesting season meant the workmen could not get onto the roof. This also had implications for the safety of not only staff but also the public in the area. Another health and safety concern for the Allen Construction was the fouling from the birds which can cause health risks due bacteria and disease.

Project overview

Allen Construction Consultancy appointed NBC to resolve a gull nesting problem at a Buildbase site in Portsmouth.

Our solution

As the UK’s bird control experts, we have the experience and knowledge to ensure a long term protection for problems of this nature. A site survey was carried out to understand the extent of the damage the gulls had caused and the size of the colony. There are many gull control solutions available but the most suitable in this situation was to install a gull netting system.

Bird proofing has many benefits to solving bird issues such as;

  • being a long term solution
  • minimal impact to buildings asthetics
  • reducing cleaning and maintenance costs due to no more bird fouling
  • netting is very versatile and can be used across a vast area

Our NBC team installed the netting system over the main building roof area including all air intake ducts restricting access to the area and preventing roosting or nesting.


There were a few challenges whilst carrying out the proofing work on the roof. The main challenge was that the roof was constructed from asbestos – a toxic fibre that can cause serious health hazards – which meant we couldn’t start the netting until a man safe system had been implemented. The NBC South team used a walkway system with crawl boards across the roof to prevent contact with the asbestos – which is fragile as well as toxic – a harnessed fall arrest system was put in place due to working at height.

The main challenge was the asbestos on the roof, due to the health hazards it can cause. To prevent any damage and loose asbestos fibre inhalation the team, instead of drilling to fix the net posts our team used 2m of stand-off fibre glass posts which supports the netting. Stand-off posts were put up in the netting to enable Allen Construction Consultancy to finish of the roof repairs under the netting safely and on-time.

A further challenge the netting needed be installed whilst Allen Construction Consultancy continued on with the roof repairs.


With the installation now in place the gulls are prevented from returning to the roof. The netting installation will provide many years of protection from the nuisance gulls. A habitual bird gulls return every year to the same nesting place so the physical barrier will protect the Buildbase roof from future damage by gulls.

Additionally with the air conditioning units now protected the risk of harmful bacteria, mites and contaminated material entering the buildings air conditioning is prevented, reducing the risk of staff illness.

As well as physical protection for the building the gull netting installation will also ensure lower maintenance and servicing costs and protection for visitors, staff and the general public.

If you have a gull or bird problem and need advice, talk to your local NBC team by calling 0333 567 2020.

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