Vandalism, a main reason for the losses, strikes the same schools again and again. Two out of three schools in urban areas but only one in three in rural areas consider property risks are a problem.

Nine out of 10 school fires are started deliberately. In the former Strathclyde Region, 95 per cent of all fires in council properties occurred in schools. The police deal with 30,000 intruder alarm calls in schools a year at a cost of about #163;1 million, but about 90 per cent turn out to be false or faulty.

The Accounts Commission’s report, A Safer Place: property risk management in schools, is based partly on a survey of more than 200 primary and secondary headteachers. Only one in three had received training in risk management, and the report says that all should.

Councils ought to identify buildings that are at risk, improve control over access to schools, install measures such as security cameras to protect people and buildings and “design crime out of schools”. Janitors have a key responsibility and are increasingly in charge of sophisticated technology. But without adequate training investment in equipment may be wasted.

Primary pupils often study the effects of vandalism and other crime on their surroundings, and are helped by visits from the police and fire service. But the report finds “little evidence of the anti-crime message being communicated to secondary pupils”.

The Accounts Commission, an independent body that audits the effective use of local authority and Health Service resources, published an influential report in September 1995 on excess capacity in schools. This led some councils to look at rationalisation proposals.

Its new survey, which began last March on the day before the Dunblane massacre, looks at a range of costs and losses from pupil protection measures to the frost damage last winter for which the bill ran into millions of pounds.

Investment in school security, for which the Scottish Office has allocated #163;25 million over three years, needs to follow risk assessment, the report says. Not all measures need be expensive, and more than half of the schools surveyed had taken action to control visitor access.

One in two of the heads questioned wanted to install or upgrade a closed-circuit television system. For a primary with 280 pupils, 13 colour cameras, some mounted on poles, would cost #163;21,000. A 950-pupil secondary would require #163;48,000 for 27 cameras and security lighting. Councils have already invested #163;1 million in security cameras, lighting and fencing. While the majority of schools have intruder alarms, only 10 per cent of primaries and 17 per cent of secondaries have security cameras.

The Accounts Commission’s estimated annual #163;18 million bill for property crime comprises #163;7 for repairing vandalism, #163;5 million for fire losses, #163;5 million in protection measures and #163;1 million for crime-prevention packages targeted on problem schools.

In addition, there are theft costs which are not recorded, the cost of decanting pupils, janitors’ time on call-outs, bills for administering repairs and processing insurance claims and higher insurance premiums as a result of claims.

“Repeated acts of vandalism leave the staff extremely deflated,” one primary in Dumfries and Galloway reported. Three-quarters of heads were concerned about the impact on teacher and pupil morale and on the ethos of the school. They felt that the visual image of a vandalised school could damage its reputation and influence parent and pupil choice. The boarding up and repair of windows is the largest element in the vandalism budget. “Broken glass is a serious problem in most schools,” the report declares.

The backlog in school maintenance and increased damage and graffiti at poorly kept buildings were major concerns for heads. Leaking roofs, inadequate insulation and the gap between reporting damage and completing permanent repairs all led to lower morale, the heads claimed.

The Accounts Commission wants councils to increase investment in crime prevention measures in the worst affected schools. For example, a four-year programme costing #163;4 million a year could reduce councils’ losses by #163;5 million after just five years. Ultimately, the amount of money that can be allocated to school security needs to be determined by democratic mandate because needs have to be weighed against competing priorities for spending.

The commission suggests that councils form an information network to share good practice. They will have to spend in the short term to save in the medium term. Although budgets are tight, the cost of damage is likely to go on rising if money is not made available and the quality of the learning environment would suffer.

A management handbook will be published in the spring, and the commission will study councils’ responses to the report. Robert Black, controller of audit, said: “We will monitor progress through our auditors to ensure that appropriate action is being taken.”

A Safer Place: property risk management in schools is available from the Accounts Commission at 18 George Street, Edinburgh EH2 2QU.