Your building is, from a pigeon's perspective, a cliff face. A very comfortable, thermally efficient, food-adjacent cliff face, conveniently located near millions of people who occasionally drop chips.
This is not a metaphor. Urban buildings genuinely replicate the key features that birds evolved to seek out — elevated ledges for nesting and roosting, sheltered overhangs, structural cavities, and proximity to reliable food sources. From a bird's point of view, the architects of the 20th century were essentially designing luxury habitat on an industrial scale, and the birds noticed.
The result is that building owners across the UK are in an ongoing, largely one-sided negotiation with a variety of species who have strong views about their tenancy rights and no awareness of the concept of a lease.
The usual suspects
The feral pigeon is by far the most common urban roost bird in the UK, and it is extraordinarily well adapted to city life. Pigeons don't technically need anything from you — they will roost on a ledge 30 centimetres wide, nest in a gap between a parapet and a drainage outlet, and return to the same spot year after year with remarkable loyalty. A single pair can produce up to six broods annually. Do the maths on that and you'll understand why a building that has a small pigeon problem in January can have a large one by October.
Starlings roost communally in enormous numbers, particularly in winter. A starling murmuration descending onto a building or group of buildings is one of the more dramatic wildlife spectacles available in British cities — and one of the more significant cleaning challenges. What several thousand starlings leave behind in a single night is considerable.
Gulls — primarily herring gulls and lesser black-backed gulls — have moved inland in significant numbers over the past few decades as coastal fish stocks have declined and urban food sources have expanded. They are large, loud, aggressive during the breeding season, and they nest on flat roofs with great enthusiasm. A gull that has decided your roof is suitable for nesting will defend it with genuine conviction. This is worth knowing before you send a maintenance team up in April.
House sparrows and jackdaws are enthusiastic colonisers of gaps and cavities in older buildings, particularly where pointing has failed and created convenient entry points. They are charming in the garden; less charming when nesting in the roof void of a listed building.
Why it matters beyond the obvious
The most visible consequence of bird activity is guano, and it is more than an aesthetic problem. Bird droppings are mildly acidic and cause measurable damage to stonework, metal, and paintwork over time. On historic buildings, guano accumulation accelerates the deterioration of already vulnerable surfaces. On modern buildings, the combination of guano and moisture retention creates conditions for biological growth — moss, lichen, algae — that speed up surface breakdown further.
There are also health considerations. Dried bird droppings can contain Cryptococcus, Histoplasma, and Chlamydophila psittaci — pathogens that pose a genuine risk during removal if proper procedures aren't followed. This is why guano clearance isn't simply a cleaning job; it requires appropriate PPE, safe working procedures, and in some cases specialist waste disposal.
Nesting materials — twigs, feathers, debris — block gutters and drains with reliable efficiency. A blocked gutter causes water to back up and penetrate building fabric. This is one of the most common routes by which birds cause significant and expensive damage to buildings, not through the nesting itself, but through the secondary water damage that follows.
And then there's the noise. Anyone who has shared office space with a gull nesting colony on the floor above will understand.
What can actually be done
The good news is that there are effective, humane, and legal solutions for most bird-related building problems. The bad news is that they all require working at height, which is where most building owners hit a practical obstacle.
Bird netting is the most comprehensive solution for excluding birds from large areas. Properly installed, it creates a physical barrier that prevents access to ledges, overhangs, and roof areas entirely. The net itself is essentially invisible from the ground and does not harm birds. The challenge is installation — netting needs to be fitted tightly, with no gaps, attached to anchor points that are positioned correctly relative to the surface being protected. A poorly installed net that sags or gaps is worse than no net, as birds can enter but not exit.
Anti-perch systems — stainless steel spike strips and tensioned wire systems — work well on ledges, windowsills, and parapets where birds land and roost but don't nest. They are not appropriate for large flat areas, and they need to be installed correctly to be effective. Spikes that are spaced too far apart or installed at the wrong angle simply don't work.
Habitat installation is the other side of the coin. For some species, particularly protected ones like peregrine falcons and bats, the goal is not exclusion but management — providing suitable nesting locations in controlled positions where they cause minimal disruption. Falcon perches and bat boxes installed in appropriate locations can redirect activity away from problematic areas while supporting biodiversity. There is also, it should be said, something genuinely satisfying about sharing your building with a pair of peregrines. They are magnificent birds and they deal with the pigeon problem more efficiently than any spike system.
A word about the law
Before any work involving nesting birds, it is important to know that all wild birds, their nests, and their eggs are protected under the Wildlife and Countryside Act 1981. Active nests cannot be disturbed or destroyed. Work involving birds or nesting areas needs to be planned around the breeding season (broadly February to August) or, where work cannot wait, carried out only after a survey by a qualified ecologist. This is not bureaucratic obstruction — it is a genuine legal obligation with real consequences for non-compliance.
Guano removal and netting installation can generally proceed outside the breeding season without complications, but if there is any possibility that active nesting is taking place, always check first.
The practical upshot
If you have birds on your building, the worst thing to do is nothing. A small problem becomes a large problem with remarkable speed, and the longer guano accumulates, the more damage it causes and the more complex and costly the removal becomes.
The right approach is a survey to understand the species involved, the extent of colonisation, and the appropriate solution — followed by professional installation of the chosen deterrent system, carried out by people who can actually reach the problem areas safely.
Which, as it happens, is exactly what we do…