This is where it’s vital to understand exactly what’s involved before you take on that charming old rectory, or a quirky water mill.

To become listed, a building must satisfy various criteria. Grade II denotes structures of “special interest, ” Grade II* “more than special interest, ” and Grade I “exceptional interest.” Of 500, 000 listed buildings in total, 92 per cent are Grade II, 5.5 per cent are Grade II* and just 2.5 per cent Grade I.

Carrying out unauthorised alterations to a listed building is a criminal offence. It could also lead to a bill of thousands of pounds to restore the building to its original state.

You should also be ready to navigate Britain’s planning laws. And don’t forget the risk of bumping into a town-hall purist, who doesn’t like your plan to put a satellite dish on an 18th-century cottage.

But while getting planning permission can sometimes be difficult, it is by no means impossible. Up to 90 per cent of listed building consent applications are approved, say English Heritage. They warn, however, that many suggested modifications, especially those involving that old heritage bugbear, double glazing, are shot down at a preliminary stage, and never make it to the planners’ desk.

Grade II listed applications are made to the local authority in the first instance. English Heritage gets involved as a matter of course only with Grade I and Grade II* listed buildings. Their advice might be sought later with Grade II listed buildings, where major change or demolition is visualised, or where the local authority has particularly asked for specialist input.

But be warned: it can all take time. Listed building consent applications need to be accompanied by detailed drawings. And there are often informal negotiations behind the scenes as owners attempt to strike a balance between the needs of modern life and the preservation of their prestigious period property.

After all, conservationists and planners are not there to make your life a misery, they are simply trying to protect the built environment. And if you look around some of Britain’s most attractive villages and towns, you can see just what a good job they have been doing.

The key is to work with planners as far as possible. Don’t make it difficult for them. Talk to your neighbours about what they have and haven’t been able to achieve, but keep your ambitions realistic.

In such a specialised field, well-informed advice is obviously at a premium. One of the best sources is the(LPOC), which holds an annual show in London (see below).

It was founded by Peter Anslow, who had struggled to find a reliable source of information about what he was and was not allowed to do when he bought a Grade II listed property in Kent. The organisation has nearly 2, 000 members paying an annual subscription of £55.

“Some of them already own a listed property, others are still at the stage of thinking of buying one, ” says LPOC’s Jo Dennis. “They find us a useful one-stop shop for advice on everything from permissible architectural changes to VAT planning.

“Insuring listed buildings can be particularly complex, but we are able to put together deals. When it comes to textbook conundrums such as whether you can replace old windows with new ones, the more help you can get, the better.”

Knight Frank’s James Carter-Brown agrees: “Professional advice is essential. There are so many variables to take into account. One local authority might be strict, for example, while the neighbouring authority is more flexible.”

The most sensible strategy, Carter-Brown reckons, is “to take a holistic approach. Decide what sort of property you want to end up with, then work with architects, designers and service engineers to make your vision practical and admissible.”

Rome wasn’t built in a day. Similarly, no listed property in heritage-conscious Britain is going to be transformed into a 21st-century home just by revving up a bulldozer and hiring an interior designer.

But work with the grain, enter into a constructive dialogue with the planning authorities and a satisfying synthesis of old and new could be within your grasp.

Before buying a listed building:

• Consult experts with specialist knowledge of the relevant architectural period. They will be able to advise you on what, if any, structural changes to the property are likely to be admissible. Try the p, or the.

• If you encounter difficulties with your local planning authority, contactat an early stage in proceedings. Its support can be crucial in the long run.

• Be sure to read the relevant sections of the English Heritage website, which contain up-to-the-minute planning advice, including guidelines on how to make listed buildings more energy efficient.

• Remember that your property is only part of a larger community. If you are surrounded by other listed buildings, your scope for manoeuvre will be correspondingly limited.

• Beware that, in a listed building, some internal features, e.g. fireplaces, are regarded as integral to the property, and cannot be altered at will.

• You can qualify for grants for repairs and VAT reductions on building works with some listed buildings. See the English Heritage site for further details.

• Don’t assume that the garden is yours to play with. There may be listed walls or trees for instance.

• Sweet-talk your neighbours. They are potential allies in any planning disputes.

The Listed Property Show takes place at Olympia, west London from February 16 -17. For details, visit

This year the Angel Awards will once again honour the heroic volunteers, resourceful fund-raisers and nimble-fingered craftsmen, who safeguard our embattled historic buildings. The awards were launched in 2011 by Lord Lloyd-Webber and English Heritage. They have been championed in this paper ever since. The 2013 awards will be launched in the spring, shortlisted and judged by a panel of experts over the summer. If you want to know more, or are involved in a heritage project, visit