Curtilo answers

Every answer below is aimed at a question people measurably search for, is written from named sources, and links to the page that handles the job itself. None of them is a landing page in disguise.

Guides for the developer who reads a plot before the offer in England and Wales: what the curtilage is, what class Q and class R allow on a barn, what a holding may build, what the rear and side envelopes and the outbuilding room are, whether a garage conversion or a porch needs an application, what a conservation area, a tree preservation order, green belt and grey belt do to a site, which developments escape biodiversity net gain, what section 278, CIL and the space standard cost, what brownfield and greenfield mean, how development land is valued and which plays a plot can carry. Every guide points at the free sheet that works the figure it discusses.

• Curtilage: the land around a house that the householder rights attach to

  What the curtilage of a house is, how it is read on a plot, what it includes and excludes, and why every permitted development limit is measured against it

• Class Q barn conversion rules: the caps, the qualifying date and prior approval

  What class Q allows on an agricultural building, the caps on dwellings and floorspace, the qualifying date, the extension and what prior approval decides.

• Class R permitted development: farm buildings to flexible commercial uses

  What class R allows on an agricultural building, the flexible commercial uses it opens, its floorspace cap and thresholds, and how it differs from class Q.

• Agricultural permitted development: the Part 6 classes by holding size, and where they stop

  What agricultural permitted development allows on a holding above and below five hectares, the prior notification, and what a developer cannot build.

• Permitted development rear extension: depths, the larger home route and the boundary

  What depth a rear extension may have under permitted development by house type, the larger home extension route, and when an application is needed.

• Side extension: half the original width, single storey, and the land that removes it

  What a side extension may be under permitted development: half the original width, single storey, within a height limit, and gone on designated land.

• Permitted development for extensions: what class A allows on a house, in one reading

  What permitted development for extensions allows on a house in one reading: the original house, the shared limits, the two-storey rear and where it stops.

• Outbuildings under permitted development: the size limit, the heights and the incidental use

  What outbuildings a plot may take under permitted development: the half-curtilage limit, the heights, the boundary rule and the incidental use.

• Do you need planning permission to convert a garage? Usually not, with two exceptions

  Whether a garage conversion needs planning permission: internal works usually do not, a parking condition does, and building regulations always apply.

• Porch permitted development (permitted development porch): class D, the ground area limit, the height limit, the distance from a highway boundary, and when a porch is an extension instead

  What porch permitted development allows: a porch outside any external door within an area limit, a height limit and a distance from the highway.

• Permitted development in conservation area: the classes that go and the ones that stay

  What a conservation area removes from permitted development: the side extension, cladding, the two-storey rear, and how article 4 directions are found.

• Tree preservation order map: where the orders are published, what an order protects, what trees in a conservation area need, and what a protected tree does to a development site

  Where the tree preservation order map is found, what an order protects, the notice trees in a conservation area need, and what a tree does to a site.

• Grey belt (green belt planning permission): the definition in national policy, how green belt land is read against the purposes, the golden rules a grey belt scheme must meet, and where the boundary is found

  What grey belt is in national policy, how a green belt plot is read against the purposes, the golden rules a scheme meets, and what green belt needs.

• BNG exemptions: the developments the biodiversity net gain requirement does not apply to, the de minimis, householder and self-build exemptions, and what net gain costs a small site that is caught

  Which developments are exempt from biodiversity net gain, how the de minimis, householder and self-build exemptions work, and what net gain costs.

• Section 278: the highways agreement and the site costs the offer forgets

  What a section 278 agreement is and costs, the visibility splay a new access needs, what CIL charges on floorspace, and the space standards dwellings meet.

• Brownfield vs greenfield: what each class does to policy, cost and value

  What brownfield and greenfield land are in planning terms, what previously developed land includes and excludes, the register, and what each does to value.

• Valuation of development land: the residual method, from the planning appraisal up

  How development land is valued by the residual method, what gross development value, costs and return are, benchmark land value and land values per acre.

• Development site: the routes a plot can carry, read before the offer

  What makes a plot a development site: the permitted envelope, class Q, the airspace classes, title splitting and build to rent, read before the offer.