Most apartment buildings have at least one vertical shaft, known as a duct, running from the ground floor to the roof. It carries water and drain pipes, and it brings a little light and air to bathrooms and kitchens. It’s also a nearly perfect home for pigeons.
Why pigeons love ducts
To a pigeon, a duct is a cliff with shelter. It offers:
- Ledges and pipes to nest on at every level
- Shade and protection from wind, rain and sun
- Peace, as nobody goes there
- Safety, as cats and crows rarely reach it
A pair that moves into a duct can raise several broods a year. Those young birds often return to nest in the same place, and in a few years a clean shaft can hold a colony.
The problems it causes
Smell. Droppings pile up on ledges and pipes, and they smell strongly in damp weather. The smell comes through ventilators into bathrooms and kitchens.
Health concerns. Dried droppings can carry fungi and bacteria. Dust from them can drift through open ventilators, which is a particular worry for older people, young children and anyone with breathing problems. Bird mites from old nests can also find their way indoors.
Noise. Ducts act like echo chambers. Cooing and flapping at dawn are loud and hard to ignore, particularly in bedrooms that share a wall.
Blocked fans. Nests built around exhaust fans stop them working, and there’s a risk of a motor overheating.
Blocked drains. Twigs, feathers and droppings can build up in gutters and open drains, leading to overflow.
Damage. Droppings are acidic and can stain and slowly damage paint and plaster. They also make pipes filthy for anyone who has to repair them.
Birds in the house. A bathroom window that opens onto a duct can let a pigeon straight inside.
Where should the net go?
There are two main approaches.
At the top of the duct
One net fitted at roof level closes the whole shaft. This is the best option because it protects every home with a single job. It’s quick for a building to organise, and everyone shares the cost. Light and air still come down through the mesh.
Check for side openings too. Some ducts are open on one face at lower floors, and those openings need to be closed as well, or birds will just come in through the side.
At your own opening
If the building can’t agree, you can protect your own flat. A net across your bathroom window, ventilator or the section of duct beside your flat will keep birds away from your home, though the wider problem remains.
Before the net goes up
Timing and preparation help.
Check for chicks. Don’t seal birds inside. If there are nests with chicks in the duct, wait for them to fly, or plan the work so that no birds are trapped.
Clear out what you can. Nests near the fixing points are removed when the net is fitted. A full clean of the shaft is usually a separate job, and it’s best done right after the net goes up, so that nothing new collects.
Protect yourself. Cleaning a duct is dirty work. Whoever does it should wear gloves and a mask, and dampen the droppings first. Working at height in a shaft needs proper safety equipment and shouldn’t be done by residents.
What makes a good duct net?
| Part | What to look for |
|---|---|
| Net | UV-stabilised bird net |
| Mesh | 50 mm, or smaller if sparrows are a problem |
| Border | Tensioned rope or coated stainless wire |
| Hooks | Stainless steel, because ducts stay damp |
| Access | A zip or hook-off panel near the pipes |
| Sealing | Close fit around pipes, with no gaps |
The access panel is easy to forget, and it’s essential. Without it, the first plumber to arrive will cut the net, and it’ll never be repaired properly.
How to get your building to agree
Often the hardest part isn’t technical. Here’s a simple approach.
- Collect evidence. Take photos of nests, droppings and blocked fans from different floors.
- Share it. Post them in the residents’ group, and explain that a net at the top protects everyone.
- Get a quote. A clear price, split between flats, is much easier to agree on than a vague idea.
- Raise it with the association. It’s usually a shared area, so the decision belongs there.
- Plan for access. Make sure someone can let the team reach the roof.
If it’s a new building, raise the matter early. It’s far easier to net a duct before nests build up than to clean one afterwards.
Light wells between houses
The same problem occurs in older streets, where houses stand close together with a narrow gap between them. Pigeons crowd in, and the noise and smell reach both homes. With both families’ agreement, one net across the top solves it for both.
Looking after a duct net
Duct nets usually last well, because they’re out of direct sun. Still, take a look at it once a year from the roof. Check the access panel is closed after any plumbing work, and look for loose corners after big storms. Remind everyone in the building that the panel needs to be closed again each time it’s used.
Is it worth doing?
Yes. A duct net is one of the cheapest fixes for one of the most unpleasant problems in apartment living. Instead of cleaning up every few months, you close the shaft once and stop thinking about it.
Learn more on our duct area safety nets page. If birds are also using your balcony or AC ledge, see pigeon nets and balcony pigeon nets.