Extensions & Conversions

At Hastings Builders Company we offer top quality extensions & conversions services for both domestic and commercial environments. We only use experienced & professional extension specialists so that you benefit from a top quality finish throughout.

We can help you build a dream extension or conversion to suit all budgets with step by step advice from our sales team from the first site visit to the last drop of paint on the walls we will assist you every step of the way.

How We Work


Hastings Builders Company has an experienced team of extension specialists who pride themselves in close attention to detail with a top quality finish every time.

We will provide a reliable and efficient service to help save you time and money with minimal stress. All works are completed within a good timescale to the highest of standard ensuring our customers return over and over again along with recommending us to friends and family. We rely on word of mouth for a lot for our extension and conversion works so having satisfied customers across the South Coast makes a big difference.

With excellent value for money, a top quality service and workmanship completed to the highest of levels there really is no need to contact anyone else.

We offer the following extension/conversion services


  • Single storey side & rear extension
  • Double storey side & rear extension
  • Loft conversions
  • Garage Conversion
  • Conservatory & orangery
  • Garden room

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Permitted Development


In some cases we can build your extension or conversion under permitted development meaning no planning permission is required. This derives from a general planning permission granted not by the local authority but by Parliament. Bear in mind that the permitted development rights which apply to many common projects for houses do not apply to flats, maisonettes or other buildings. Similarly, commercial properties have different permitted development rights to dwellings.

In some areas of the country, known generally as ‘designated areas’, permitted development rights are more restricted. Permitted development is restricted in:
  • A Conservation Area
  • A National Park
  • An Area of Outstanding Natural Beauty
  • A World Heritage Site or
  • The Norfolk or Suffolk Broads.
You will need to apply for planning permission for certain types of work which do not need an application in other areas. There are also different requirements if the property is a listed building. We will always help our customers and apply on their behalf or, if they are comfortable doing so, they can apply themselves.

Our general advice is that you should contact your local planning authority and discuss your proposal before any work begins. They will be able to inform you of any reason why the development may not be permitted and if you need to apply for planning permission for all or part of the work. You can then come to us and we can take on board the information so far and help plan the next stages with you.

To read more on permitted development click here.

Planning Permission


When beginning a project, you must consider whether the development will need to have planning permission or building regulations approval or your project may need both. These are two separate applications and must be applied for individually by the customer or by ourselves. We work closely with a local Building Control office who we would always suggest to use but your free to instruct who you wish. For planning permission, we can apply for you offering a start to finish service taking all the stress of planning away from you. Most planning and building control applications are now submitted online. To view the planning portals application page please click here.

You’ll probably need planning permission if you want to:
  • Build something new to your existing building or on a plot of land.
  • Make a major change to your existing building, eg building an extension.
  • Change the use of your building.
If your project needs planning permission and you do the work without getting it, you can be served an ‘enforcement notice’ ordering you to undo all the changes you have made.

We would never start any works without planning permission being granted prior to the works to avoid any enforcement’s that could be served in the future.

Single storey side extensions are a great way to extend your property, add value & add additional living space. An extension to the side of your house is considered to be a Permitted Development, not requiring a full planning permission, if the following limits and conditions are met.

On designated land, cladding of any part of the exterior of a dwelling (and extensions) with stone, artificial stone, pebble dash, render, timber, plastic or tiles is NOT Permitted Development.

Extensions (including previous extensions) and other buildings must not exceed 50% of the total area of land around the original house. Sheds and other outbuildings must be included when calculating the above 50% limit.

Extensions forward of the principal elevation or side elevation of a house and fronting a highway are NOT Permitted Development.

On designated land side extensions are NOT Permitted Development.

Materials used in exterior work are to be similar in appearance to those of the exterior of the existing house. This condition does not apply when the extension is a conservatory.

The width of the side extension must not have a width greater than half the width of the original house.

Side extensions are to be single storey with a maximum height of four meters.

If the extension is within two meters of a boundary, maximum eaves height should be no higher than three meters to be a Permitted Development.

The maximum eaves and ridge height of extension must be no higher than the existing house.

Single storey rear extensions are a great way to extend your property, add value & add additional living space. An extension to the rear of your house is considered to be a Permitted Development, not requiring a full planning permission, if the following limits and conditions are met.

On designated land, cladding of any part of the exterior of a dwelling (and extensions) with stone, artificial stone, pebble dash, render, timber, plastic or tiles is NOT Permitted Development.

Extensions (including previous extensions) and other buildings must not exceed 50% of the total area of land around the original house. Sheds and other outbuildings must be included when calculating the above 50% limit.

Materials used in exterior work are to be similar in appearance to those of the exterior of the existing house. This condition does not apply when the extension is a conservatory.

If the extension is within two meters of a boundary, maximum eaves height should be no higher than three meters to be a Permitted Development.

Single storey rear extensions must not extend beyond the rear of the original house by more than 3 meters, if an attached house (semi detached/town house/ terraced) or by 4 meters if a detached house.

Single storey rear extensions must not exceed a height of 4 meters.

The maximum eaves and ridge height of extension must be no higher than the existing house.

Double storey extensions are a great way to extend your property, add value & add additional living space. An extension to your house is considered to be a Permitted Development, not requiring a full planning permission, if the following limits and conditions are met.

On designated land extensions of more than one storey are not a Permitted Development.

Extensions (including previous extensions) and other buildings must not exceed 50% of the total area of land around the original house. Sheds and other outbuildings must be included when calculating the above 50% limit.

Maximum eaves and ridge height of the extension must be no higher than the existing house. If the extension is within two meters of a boundary the maximum eaves height should be no higher than three meters to be a Permitted Development.

Extensions of more than one storey must not extend beyond the rear wall of the original house* by more than three meters or be within seven meters of any boundary opposite the rear wall of the house.

The roof pitch of extensions higher than one storey are to match that of the existing house, as far as is practicable.

Materials used in the exterior work are to be similar in appearance to those of the exterior of the existing house.

Front porches are a great way to extend your property, add value & add additional space. A porch to the front of your house is considered to be a Permitted Development, not requiring a full planning permission, if the following limits and conditions are met.

The ground area of the porch, measured externally, is not to exceed three square meters.

The highest part of the porch is not to exceed three meters.

No part of the porch is to be within two meters of any boundary that fronts a highway.

Loft conversions are a great way to extend your property, add value & add additional space. A loft conversion is considered to be a Permitted Development, not requiring a full planning permission, if the following limits and conditions are met.

Loft conversions are NOT a Permitted Development for houses on designated land.

To be a Permitted Development any additional roof space created must not exceed 40 cubic metres for terraced houses & 50 cubic metres for detached and semi-detached houses. Bear in mind that any previous roof space additions must be included within this volume allowance. Although you may not have created additional space a previous owner may have done so.

An extension beyond the plane of the existing roof slope of the principal elevation that fronts a highway is NOT a Permitted Development.

Materials are to be similar in appearance to the existing house.

No part of the extension is to be higher than the highest part of the existing roof.

Verandas, balconies or raised platforms are NOT a Permitted Development.

Any side-facing windows must be obscure-glazed and non-opening unless the parts which can be opened are more than 1.7 metres above the floor of the room in which it is installed.

Roof extensions, apart from hip to gable ones are to be set back, as far as is practicable, at least 20cms from the eaves. The 20cm distance is measured along the roof plane. The roof enlargement cannot overhang the outer face of the wall of the original house*.

Work on a loft or a roof may affect bats. You need to consider protected species when planning work of this type. A survey may be needed, and if bats are using the building, a licence may be required.