, Property
You buy a Georgian terrace, grade II, and the plan is straightforward. Strip the plaster back to brick in the front room, take out the partition that somebody put in during the 1970s, replace the sash windows with double glazed units in the same style, and repoint the front.
Three of those four need listed building consent. The fourth might, depending on what mortar you use. And the partition from the 1970s is more complicated than you would like, because whether it is listed depends on nothing more helpful than whether it is part of the building.
The listing covers the whole building, not the interesting bits
The Planning (Listed Buildings and Conservation Areas) Act 1990 governs England and Wales. Scotland has its own Act of 1997, administered by Historic Environment Scotland, with categories A, B and C rather than grades. Northern Ireland uses grades A, B+, B1 and B2.
In England the grades are I, II* and II, and the great majority of listed buildings are grade II. The grade affects how much scrutiny you get and how much weight is given to harm. It does not change what needs consent.
The point people get wrong is scope. The listing is of the building, which means the whole of it, inside and out, including later additions. It extends to objects and structures fixed to the building, and to free-standing structures within the curtilage that were there before 1 July 1948. A stable block, a garden wall, a boundary railing, an outbuilding: potentially all listed, none of them mentioned in the list entry, because the list entry is a description for identification rather than a schedule of what is protected.
The test for consent is whether the works would affect the character of the building as a building of special architectural or historic interest. That is a low bar and it is deliberately broad. Internal plasterwork, joinery, staircases, chimneypieces, floorboards, doors, ironmongery, and the windows can all fall within it. Removing a twentieth century partition may well be fine, but it is fine because the local planning authority says so on an application, not because you decided it was.
The offence is strict and it does not expire
Section 9 of the 1990 Act makes it an offence to execute works for the demolition, alteration or extension of a listed building without consent, in a way that affects its character.
It is strict liability in the sense that not knowing the building was listed is not a defence, and neither is a builder who told you it would be fine. The penalty on summary conviction is a fine, and on indictment a fine and imprisonment. Prosecutions are not common, but they happen, and local authorities do bring them where the harm is significant and obvious.
More important for anyone developing is enforcement. An ordinary breach of planning control becomes immune after a period, ten years in England for most operational development following the changes made by the Levelling-up and Regeneration Act 2023. There is no equivalent immunity for unauthorised works to a listed building. A listed building enforcement notice can be served at any time, requiring the building to be restored to its former state. Buying a house where somebody else ripped out the staircase in 1998 does not put the problem behind you, it transfers it to you.
Which is why the survey question for any listed purchase is not what condition is it in, it is what has been done to it and was any of it consented. Ask for the consents. If there are none and there is obviously new work, price for putting it back.
Conservation areas are a different and weaker control
A conservation area designation under section 69 of the Act protects the character and appearance of an area rather than individual buildings. Most buildings in a conservation area are not listed.
Three things change. Demolition of a building in a conservation area requires planning permission, and doing it without permission is an offence. Permitted development rights are reduced, so cladding, satellite dishes, some roof alterations and some extensions that would be permitted elsewhere need an application. And trees are protected: you must give the local planning authority six weeks' notice before cutting down or carrying out work to a tree in a conservation area, which gives it the chance to make a tree preservation order.
Many authorities go further with an article 4 direction, which removes specified permitted development rights across a defined area. Article 4 directions are what stop uPVC windows appearing on a Victorian street, and they are why two apparently identical houses two miles apart have completely different rules. Check for one before you price anything. It is on the local planning authority's website and it takes five minutes.
The costs land in places you did not budget for
Consent is only the start of the money.
The first cost is professional. A listed application usually needs a heritage statement, prepared by someone who understands the building, setting out its significance and assessing the impact of your proposal against it. Authorities consult their conservation officer, and for grade I and II* works they consult Historic England. A good heritage statement is the difference between a consent and a refusal, and it is not a form you fill in.
The second cost is method. Lime mortar rather than cement, because cement traps moisture in soft brick and causes the decay it was supposed to prevent. Slim profile secondary glazing or slimline units in existing frames rather than replacement windows. Traditional lath and plaster repair. Craftsmen who work this way exist, there are fewer of them than there are jobs, and they are booked.
The third cost is VAT, and it is the one that catches developers. The zero rate for approved alterations to listed buildings was withdrawn with effect from 1 October 2012. Approved alterations and repairs are now standard rated at 20% in the ordinary way. There remain reduced rate routes in other circumstances, such as a residential property empty for two years or more, or a conversion changing the number of dwellings, and those are worth checking on any particular scheme, but the old heritage relief is gone.
Put those three together and a listed refurbishment can run comfortably ahead of the same work on an unlisted building of the same size. That is not a reason to avoid them. It is a reason to price them properly, because the purchase price is where you recover it.
Where this shows up in the game
Property, construction and architecture arrive in Business Baron with the Property & Construction Track, an add-on to the full game. Planning runs as a process with dates rather than a switch, and consents come from bodies with their own timetables. A building with a rulebook attached takes longer, and the time is time you have already borrowed against.