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House Extension Project

House Extensions Specialist Builders Company

Sebastian & Co. Builders Ltd are house extensions speciastist builders. Over the years we have carried out work on various house extension and alteration projects ranging from single storey to double storey.

From start- foundations, brickwork, insulation etc to internal- finishing, decorating works.

Sebastian & Co. Builders Ltd will help you with all your house extension design and building. Please look no further and contact us for a free quotation without obligation.

Cost of buiding a home extension

As a rough idea you can typically say that extending a house will cost at least £1200 per m² or 120 per ft² including basic internal work (plumbing, electrics). The larger your extension, the less it will cost per square metre due to economies of scale coming into force.

Sebastian & Co. Builders Ltd will give you a free quotation on your project.

What is allowed- house extensions built in Croydon, Bromley, Surrey

An extension or addition to your house is considered to be permitted development, not requiring an application for planning permission, provided certain limits and conditions are met.

Sebastian & Co. Builders Ltd can advise you on your extension design and explain what is allowed.

Planning regulations probably changing soon for home extensions.

In September 2012 Downing Street announced a consultation on easing the rules on home extensions of up to eight metres. You can read more about how it will change house extension building regulations on

Pictures of building house extensions carried out by us

Rear, single storey house extension built in Croydon:
Rear, single storey house extension built in Croydon

Porch in Croydon (the same house- during the job):
Porch in Croydon

Porch in Croydon (the same house- after the job. All nicely rendered, concrete blocks drivaway, and some landscaping done):
Porch in Croydon- the same house- after the job

Single Storey Side House Extension:
Single Storey Side Extension

Double Storey Side Extension:
Double Storey Side Extension

Another extension:
Another extension

Large one (Surrey):
Large extension

Extension building job- foundations:
Extension building job- foundations

House extended near Bromley:
Extension near Bromley

Sebastian & Co. Builders Phone Number 020 8239 0986
    Main operation area:
  • Croydon
  • Bromley
  • Kingston
  • Lambeth
  • Lewisham
  • Merton
  • Richmond
  • Sutton
  • Wandsworth