What is making that noise in my loft?

Start with when you hear it

A regular tick or creak as the heating goes off is usually timber and pipes cooling. Animal noise moves about, stops and starts again.

Then look at the droppings

Go up in daylight with a torch and gloves, and look along the joists, on top of the insulation and near the eaves.

• Rat: 9 to 14 mm, thick, sausage-shaped, often in groups along a run.
• Mouse: 3 to 6 mm, thin and pointed like a grain of rice, scattered.
• Grey squirrel: about 8 to 12 mm and cylindrical, often near a nest of shredded insulation.
• Bat: about the size of a mouse dropping, but dry. The Bat Conservation Trust says a bat dropping crumbles under light pressure and looks slightly sparkly, because it is made of insect remains. Press one with a stick, not your fingers.

Photograph what you find next to a coin for scale, so whoever you call can tell what it is.

Other signs to check

Rats and mice gnaw. Look for chewed cables, pipe lagging and wood, greasy marks along beams, and tunnels through the insulation. Squirrels build a large, untidy nest, called a drey, often from torn insulation, and get in through holes at the roofline. Birds leave twigs and nest material in the eaves and white splashes below.

Bats leave very little. Natural Resources Wales says they do not build nests, bring in nesting material or chew wires, insulation or wood. Droppings under a gap in the roof may be the only sign.

If it might be bats

All bat species and their roosts are protected. GOV.UK lists the offences: deliberately capturing, injuring or killing a bat; damaging or destroying a breeding or resting place; blocking access to a roost; and disturbing a bat in its roost. The penalty can be up to six months in prison, an unlimited fine, or both.

Bats come back to the same roost year after year, and Natural Resources Wales notes they are most noticeable in early summer, when females gather to raise young. So do not seal the gap they use, even in winter, and check before any roof work or timber treatment.

The National Bat Helpline, 0345 1300 228, gives free advice to householders on behalf of Natural England and can arrange a volunteer to visit.

If it might be nesting birds

Under the Wildlife and Countryside Act 1981 it is an offence to intentionally take, damage or destroy the nest of any wild bird while it is in use or being built, or to take or destroy its eggs. That covers common birds such as starlings and house sparrows in the eaves, not only rare ones. The law allows limited action against a few species, such as feral pigeons, only for set purposes and on Natural England's conditions, so leave that to a professional.

Wait until the young have flown and the nest is empty, then block the gap, usually in autumn or winter. Pigeons and gulls that use the roof every year need proofing rather than nest removal. See bird control for the options.

If it is squirrels, rats or mice

It is illegal to release a grey squirrel once it has been caught, so a pest controller will remove them for good and proof the holes. Spring and summer litters may be in the drey, so a firm should check before trapping. See squirrel removal and what it costs.

Rats in a loft need dealing with soon, because they gnaw cables. Mice are smaller but breed quickly. Do not block the way in until a professional confirms they have gone, or you may trap them inside. Read about rat control and mouse control. Many councils treat rats and mice, so check your council. If you rent, holes in the roof are a repair, and Shelter's advice is that your landlord must deal with pests that come in through a repair they are responsible for.