The short answer
Twigs or straw in the grate, scratching or cooing in the flue and smoke coming back into the room all point to a nest. Never light a fire to burn it out. It can start a chimney fire or push smoke and carbon monoxide into the house. Leave an active nest until the birds have gone, then have a sweep remove it and fit a cowl or guard.
Why birds choose Maltese chimneys
For most of the year, chimneys in Malta and Gozo are not in use. Fires are lit for a few months in winter, and from spring to autumn the flue sits cold, quiet and sheltered. To a pigeon or sparrow, an open chimney pot on a flat roof is a ready-made nest site, high up, out of the wind and away from cats.
Older farmhouses and townhouses are especially attractive. Their stone chimneys often have wide flues, rough inner surfaces and ledges where nest material catches. Chimneys that have been unused for years, common in houses bought for renovation, can hold several seasons of nests.
Signs of a nest
You may notice:
- Twigs, straw, feathers or droppings falling into the grate or onto the hearth.
- Scratching, flapping or cooing coming from the flue, often early in the morning.
- A musty or unpleasant smell from the fireplace, especially in warm weather.
- Flies or insects around the fireplace.
- Smoke coming back into the room when you first light a fire in autumn.
- A fire that will not draw, or a stove that struggles to stay lit.
A nest is not the only cause of these. Soot and creosote build-up, a collapsed liner or debris can do the same. Our guide on why a fireplace smokes into the room covers the other causes.
Nest or general debris?
A nest is usually a dense mass of twigs, straw, grass and sometimes plastic or string, woven together. Loose soot, crumbled mortar and leaves look different. If material keeps falling, or you see feathers and droppings, a nest is likely. A sweep can look up the flue with a light or camera and tell you.
Never light a fire to burn a nest out
This is the one thing not to do. Nest material is dry and burns quickly. It can:
- set alight creosote lining the flue, starting a chimney fire,
- block the flue as it collapses, sending smoke back into the room,
- push carbon monoxide into the house, because the flue cannot clear the gases.
Smoke alone will not shift a nest either. It just fills the room. See what is creosote for why build-up in the flue makes this more dangerous.
If the nest is active
If you can hear chicks or see adult birds coming and going, leave the nest alone until the young have fledged and gone. Do not light fires, block the pot or try to pull the nest down while birds are inside. They can end up trapped in the flue.
Plan ahead instead. Nesting is mostly a spring and early summer issue. If you book your sweep for September or October, before the heating season, any nest is usually empty by then.
How a sweep removes a nest
A sweep will usually:
- Seal off the fireplace or stove to keep dust and debris out of the room.
- Inspect the flue to find the nest and check for damage.
- Break the nest up and bring it down with rods and brushes, sometimes working from the roof.
- Remove all the material and sweep the flue to clear soot and creosote at the same time.
- Check the flue draws properly before you light a fire.
Nests can be packed tight and are often heavier than expected. It is not a job for a broom handle from below.
Keeping birds out
Once the flue is clear:
- Fit a cowl or mesh guard on the chimney pot. A sweep can recommend one that suits your chimney and appliance, so it keeps birds out without restricting the draw.
- Keep the annual sweep. A yearly sweep before the season finds new material early. See how often to sweep a chimney.
- Check after spring. If you see birds around the pot in spring, have it looked at before autumn.
- Look at the rest of the roof. Pigeons nesting in chimneys often also nest under solar panels on raised frames.
Fit a carbon monoxide alarm
Any blocked flue can push carbon monoxide into the house. If you have a fireplace or stove, fit a CO alarm in the same room. Our guide on carbon monoxide alarms for homes with stoves and fireplaces explains where. If you ever suspect a chimney fire or CO poisoning, get everyone out and call 112.
Booking
We arrange chimney sweeping, nest removal and pre-season checks across Malta and Gozo. If you have seen signs of a nest, get a quote before you light the first fire.