Basildon has no householder design guide
Many councils publish a booklet with a 45 degree diagram and maximum depths. Basildon doesn't. Its adopted planning documents run to a shop front guide for Billericay, parking standards from 2009 and an old set of development control guidelines from 1997, and none of them deals with house extensions. So when you do need permission, the planner is working mainly from one saved policy in the 1998 local plan, BAS BE12.
BAS BE12 lists the harm that justifies a refusal. Damage to the character of the street. Overlooking. Noise and disturbance. Overshadowing, or a building that is overdominant next to its neighbours. Traffic danger. There are no fixed numbers in it, which cuts both ways. Nothing stops a deep extension on paper, but nothing protects a borderline one either. Stand in your neighbour's garden and look back at the plan.
On a new town terrace the neighbour's back windows sit a few metres from the shared fence. Those windows are where an officer starts.
Clay, slipped hillsides and the brooks
Basildon is built on London Clay. Before the new town, farms here were sold off in small plots, partly because the soil was such poor, heavy clay. On the higher ground at Langdon Hills, sandier Claygate Beds and Bagshot Sand sit on top. The British Geological Survey says clay that shrinks and swells mostly moves in the top two metres, and trees growing or being felled make it worse. Tell whoever designs your footings about every big tree within reach of the new wall.
Two hills need more care. GeoEssex describes land-slipped ground on the south side of Vange Hill, and St Michael's Hill in Pitsea, an old Thames cliff line, is another example. On a sloping plot there, budget for a site investigation before the engineer draws anything.
Water is the other question. Land along the River Crouch on the northern edge is in Flood Zones 2 and 3, and Nevendon Brook and Basildon Brook both feature in Essex County Council's surface water plan. If your house is in Zone 2 or 3, an application needs a flood risk assessment. For anything up to 250 square metres the Environment Agency's standing advice covers it, and it will ask for the new floor 600mm above the estimated flood level or for flood resilient construction.
Matching the build to the house
About a third of the borough's homes are terraced. Here is where each type tends to fit.
Single-storey rear. The obvious first step on a Fryerns or Vange terrace. Without an application you can add 3 metres to the original back wall of a terraced or semi-detached house, or 4 metres on a detached one, up to 4 metres high. Go to 6 or 8 metres and the neighbours get a say through prior approval, and you wait up to 42 days.
Kitchen. Most of these terraces have small back kitchens. A rooflight above the worktop gives you daylight without putting a new window opposite the house next door.
Open plan. Taking out the old back wall means a steel beam and padstones. On London Clay the pads under the posts need the same thought as the new footings.
Side return. Rare in the new town, where most terraces have no side passage at all. Billericay's older streets are the likelier place to find one.
Wrap-around. Suits end terraces and semis with land at the side. The side part means a planning application, so BAS BE12's street scene test comes in.
Two-storey. A rear one can go 3 metres without permission if it stays 7 metres from the back boundary, which short new town gardens often can't manage. Over a side garden it always needs an application, and overdominance is the usual worry.
Ground-floor bedroom. Often asked for on the plotland bungalows around Langdon Hills and Wickford. In the Green Belt it counts against the council's floor area cap, so measure first.
Home office. Where the garden is small, an attached room beats a cabin at the end of the lawn.
Planning. Noak Bridge's 1996 Article 4 direction removes the right to extend without permission, porches included. In the borough's other three conservation areas, Billericay and the two Bursteads, side extensions and anything over one storey at the back need permission, and cladding isn't allowed.
Cost and value. We don't publish prices. Deep footings near trees, a sloping site on Vange Hill or a raised floor in a flood zone each change the sum.
Plotlands and the Green Belt limit
Most of the borough outside the towns is Green Belt, including thirteen plotland settlements such as Crays Hill, Fairmead and Stormont Way. Here saved policy BAS GB4 limits how far a house can be enlarged when an application is needed. The limit is measured against the original house, meaning as built, or as it stood on 1 July 1948.
Ask the planners which parts of your house count towards the limit before anyone draws. Many plotland shacks were rebuilt or enlarged long ago, so the allowance may already be spent. The council itself warns that some homes can't be extended at all. Find the old permissions on its e-Planning site before you pay for drawings.
Where these facts come from
- Basildon Council: adopted local plan and supplementary documents
- Saved policy BAS BE12, development control (transcription)
- Basildon Council: Green Belt information
- Basildon Council: Green Belt information
- Noak Bridge Neighbourhood Plan (Article 4 direction, section 6.2.2)
- GeoEssex: Basildon geological sites
- British Geological Survey: GeoSure shrink-swell
- GOV.UK: flood risk assessment standing advice
- GOV.UK: permitted development rights for householders, technical guidance
- Essex Design Guide: South Essex surface water management plan
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Questions people in Basildon ask
My neighbour wants to build 6 metres out from the back of our terrace. Can I object?
Yes. A rear extension beyond 3 metres on a terrace or semi goes through prior approval, and the council has to tell adjoining neighbours. It then looks at the effect on their light and outlook before deciding.
We're in Noak Bridge. Do we need permission for a conservatory?
Almost certainly. The 1996 Article 4 direction covers enlarging the house, and a conservatory is an enlargement. It also covers porches.
Our plotland bungalow near Wickford has a detached garage. Does it count against the Green Belt allowance?
It may. Green Belt policy BAS GB4 measures growth against the original house, and an attached garage or a conservatory can count. Ask the planners how they'll treat your plot, garage included, before you design around it.
We live on the slope below Vange Hill. Is that a problem for an extension?
It can be. GeoEssex records land-slipped ground on that side of the hill. Building control will expect foundations designed for the site, so have a structural engineer and a ground investigation lined up early.