The responsibility for repair lies with Mr Thomas, and he could face a big compensation claim if a passer-by trips on the pavement.
Local authorities have no responsibility for maintaining unadopted roads, some of which are private roads (which are not public rights of way) or private streets (which are). Some unadopted roads are on recently-built estates where the roads were of inadequate standard, often because the builder went out of business before completing the work.
Mr Thomas was aware when he bought the house in 1981 that the pavement was his responsibility, 'but the pavement was in good repair then, and it didn't particularly worry me'.
He approached Leicester council to see if it would take on responsibility for it, but the council said it could only do so if all the residents club together to put the pavement into good condition. But some of Mr Thomas's neighbours are not interested, and the cost of bringing the path up to standard could be high, about pounds 12 per square metre, plus pounds 10 per metre of kerb.
Mr Thomas might consider himself lucky that only his pavement is unadopted. Thousands of home owners are also responsible for their roads. Audrey Blaney of Ibstock in Leicestershire lives on an unadopted road, which regularly floods because there is no street drainage.
'We get puddles everywhere,' Mrs Blaney said. Recently she needed a new sewer, costing pounds 300, which her insurer paid for. She now needs new outlet pipes, which she hopes her insurer will also pay for.
Mrs Blaney and her husband, who are now retired, bought their property in 1968, and the council at that time wanted to adopt the street for a cost of pounds 200. Although the Blaneys were willing to do this their neighbours were not, and still one of them refuses to pay to have the road adopted - which could cost pounds 140 per metre of frontage.
Sharon Harris, a neighbour of Mrs Blaney, had a baby last week, and the ambulance had difficulty in getting down the road. Mr and Mrs Harris had already found out that unadopted roads cost money. When they had an extension built five years ago they had to pay an extra pounds 300 to move the street's land drain. Although it was not functioning and maintenance was the responsibility of the whole street the Harrises decided to pay the cost themselves because of the difficulty and expense in collecting money from neighbours.
At least now, with the new land drain, houses in the street no longer flood. Previously the council brought along sand bags to the road every time there were heavy rains.
'We've been here 12 years and knew the street was unadopted but we weren't aware of the implications. We are always filling in holes in the road,' Mrs Harris said.
Mr and Mrs Harris are unhappy that they would have to pay more than their neighbours for adoption. They have a semi-detached house, while most of their neighbours own small terraced properties. Home owners are responsible for the street outside their own property - the wider the house the greater the responsibility.
It is important for householders to maintain unadopted roads and pavements to good standard, because injuries caused by neglect could lead to compensation claims that ordinary insurance policies are unlikely to cover. Home owners should check deeds to establish whether roads and pavements are jointly owned, in which case they should take out a joint insurance policy.
Peter Topple, personal insurances underwriting manager of Legal & General, said: 'Liability cover on a property is only in respect of accidents within the confines of the home and garden.' Home owners who live in unadopted roads must notify their insurer of that fact - failure to advise could invalidate some claims. Premiums for policies that do include the road and pavement are likely to be higher. Failure to properly maintain a road or pavement could also lead to invalidation of a claim, but damage to pavement or road can be a basis for claiming on a policy.
The process of adopting a road is likely to take several years. Even though the council will charge residents for repair work, it has to be met in the first instance by the council and budgets for this are generally inadequate to keep up with demand. In some areas it would take decades to meet all the requests at the current rate of progress. In Leicestershire there are hundreds of unadopted roads, and the county council says there are many more it is unaware of.
Mr Thomas, Mrs Blaney and Mrs Harris each said that when agreeing purchase prices they did not take into account that the road was unadopted. Yet the cost can be significant. David Weston of the Association of County Councils said: 'Anyone doing conveyancing work who has their wits about them should underscore it. It should be borne in mind when buying a house - it could force you to put your hand in your pocket.'