Grey Squirrels in the Loft: Signs and Risks

The grey squirrel (Sciurus carolinensis) was brought to Britain from North America in the 1870s and is now found in every London park and garden. Outdoors it is easy to enjoy. In a loft it is a serious pest: it chews timber, insulation and electrical cables, and it does not leave on its own.

How to Identify a Grey Squirrel

Grey squirrels have silver-grey fur, often with a brown tinge on the back and feet, a white underside and a long, bushy tail edged with white. They are larger and heavier than the native red squirrel, which is no longer found in London.

They build round nests of twigs and leaves, called dreys, high in trees. When they can get into a roof, they nest in the loft instead, shredding insulation for bedding.

Signs of Squirrels in the Loft

• Daytime noise: scratching, scurrying and rolling sounds, mostly at dawn and dusk. Rats and mice are heard mainly at night.
• Droppings: about 8 to 10 mm long, rounded, similar to rat droppings.
• Chewed timber, cables, pipes and stored items.
• Torn-up insulation pulled into a nest.
• Holes and gnaw marks in fascia boards, soffits and under roof tiles.
• Squirrels on the roof, especially running along the gutter line to the same spot.

Can Squirrels Damage My Property?

Yes, and quickly. Squirrels gnaw to keep their teeth short, and in a loft they chew roof timbers, water pipes and electrical wiring. Stripped cables are a fire risk and chewed pipes cause leaks. They also contaminate insulation and water tanks with droppings and urine, and can drown in uncovered tanks.

In gardens they strip bark from trees, dig up bulbs and raid bird feeders.

How to Stop Squirrels Getting In

• Cut back branches so that none are within about 3 metres of the roof.
• Repair the roofline: replace rotten fascias and soffits and refit loose tiles.
• Fit strong metal mesh over vents and gaps. Squirrels chew through wood, plastic and foam.
• Use squirrel-proof bird feeders and clear spilled seed.
• Never seal an entry hole while squirrels may be inside. Trapped squirrels cause far more damage trying to get out, and young may be left to die.

Squirrels and the Law

Grey squirrels are an invasive species. It is legal to control them, but it is against the law to release a grey squirrel once it has been caught, so they cannot be trapped and let go somewhere else. Control must be humane, and traps have to be checked at least once a day. For most people that makes squirrel removal a job for a professional.

Frequently Asked Questions

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