The weather’s finally warmed up, which should signal the start of the DIY season.

Almost a quarter (24 per cent) of Brits are planning to do more DIY this year than last, spending an average of £865, according to a recent poll by DIY chain B&Q.

Decorating is one thing, but major home improvements are often less straightforward – even if planning permission isn’t required, other permissions may be.

With listed buildings, home improvements are rarely as simple as they seem, as the listing applies to both the inside and outside.

The safest option is to check with your local council’s conservation officer before making any changes, because work that seems minor can require listed building consent from the council.

The process of seeking consent is similar to that of planning permission, but in complicated cases and ones involving certain types of work and Grade I and Grade II-listed buildings (the most important ones), the case will be referred to English Heritage (see www.english-heritage.org.uk for advice).

You can appeal if consent is refused, but doing the work without consent is a criminal offence, and you can be forced to reverse any unauthorised changes.

Special rules also apply to properties on ‘designated land’, such as conservation areas and Areas of Outstanding Natural Beauty.

The permitted development rules are different here, meaning there’s less you can do to your home without planning permission For example, side extensions and loft conversions are not permitted development for houses on designated land, but they can be done without planning on most other houses, as long as the rules are followed.

Conservation areas have special historical or architectural interest, and councils are keen to preserve their appearance and character. This is laudable, but it can make life difficult for home improvers because it gives councils more say over minor changes to buildings, gardens and trees.

In addition, extra restrictions apply to certain properties. If a property has been subject to an Article 4 Direction, planning permission is required for home improvements that wouldn’t normally need it, such as replacing the windows.

If your home’s leasehold, it’s not just the local council you have to worry about. Most leases have a clause stating that alterations must be approved by the freeholder (by them signing a licence to alter), although the lease will probably also say that permission can’t reasonably be refused. Even if you own a share of the freehold, you still need the written permission of the other freeholders.

Getting your freeholder or co-freeholders to agree can be a long and painful process, and some have been known to unreasonably refuse or to ask for money in return for granting permission.

Doing alterations without a signed licence to alter from the freeholder/s can cause problems when you sell if you’re in breach of the lease, even if they’re also in breach of it.

The other way in which your neighbours may become involved in your home improvements is if you need a ‘party wall’ agreement with them.

Party walls are ones that you share with your neighbours in terraced and semi-detached houses. They can also be shared floors/ceilings in flats, and walls built astride a boundary in the garden.

The Party Wall Act 1996 governs building work involving these, plus new boundary walls and some excavations close to neighbouring buildings.

The purpose of the act is to minimise or avoid disputes between neighbours over building work affecting party walls by setting out how it should be done.

You start by serving a notice on the affected neighbours and if they don’t agree to the work, you resolve the ‘dispute’ with party wall surveyors and agreements. Again, this can be a difficult and expensive process, but it’s one you avoid at your peril.