Two-storey extensions in Southend-on-Sea
We design, get approval for and build two-storey extensions in Southend-on-Sea and the surrounding area. Choose the type of extension below or book a free site visit.
Southend-on-Sea at a glance
- Postcode districts
- SS0, SS1, SS2 and SS3
- Area
- Essex, England
- Price region
- East of England
- Nearest towns
- Rochford (3.1 miles), Hadleigh (4.6 miles), Rayleigh (5.8 miles), Canvey Island (5.8 miles)
- Approvals
- Two-storey rear: up to 3 m deep and 7 m from the rear boundary under permitted development. Side, wraparound and front: planning permission.
We cover Southend-on-Sea (SS0, SS1, SS2 and SS3) and the places around it, including Rochford (3.1 miles), Hadleigh (4.6 miles) and Rayleigh.
Extensions available in Southend-on-Sea
Two-storey rear extensions
Southend-on-Sea guide price from £57,500, Standard spec.
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Two-storey side extensions
Guide from £88,500 in Southend-on-Sea, including VAT.
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Two-storey wraparound extensions
Our East of England guide starts at £124,000 for this type.
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Part single, part two-storey extensions
Guide from £74,000 in Southend-on-Sea, including VAT.
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Extensions over a garage
Our East of England guide starts at £32,500 for this type.
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First-floor extensions
Design, approvals and build for Southend-on-Sea homes. Guide from £26,000.
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Two-storey extensions for semi-detached houses
From £57,500 in Southend-on-Sea. Free visit to firm it up.
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Two-storey extensions for detached houses
Our East of England guide starts at £88,500 for this type.
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Kitchen extensions with bedrooms above
For homes in Southend-on-Sea: typical guide from £57,500 (before kitchen units).
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Extra bedroom and en-suite extensions
For homes in Southend-on-Sea: typical guide from £57,500 (plus en-suite).
Learn moreWhich type suits your house?
Which type suits your house in Southend-on-Sea depends mostly on where you have room. A deep garden points to a rear extension; space beside the house points to a side or over-garage extension; a house that already has a single-storey extension can often take a first floor on top.
Also available in Essex
- Two-storey front extensions
- Two-storey extensions for end-of-terrace houses
- Two-storey annexe extensions
- Garage conversions with a room above
- Two-storey extension plans and drawings
- Planning permission for two-storey extensions
- Structural engineering for two-storey extensions
- Building regulations for two-storey extensions
- Party wall notices for extensions
- Design and build two-storey extensions
Rules for Southend-on-Sea
Southend-on-Sea is in England. Two-storey rear: up to 3 m deep and 7 m from the rear boundary under permitted development. Side, wraparound and front: planning permission. Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.
The full England rules explained
Questions about extensions in Southend-on-Sea
Do you cover Southend-on-Sea?
Yes. We cover Southend-on-Sea (SS0, SS1, SS2 and SS3) and the surrounding area, including Rochford and Hadleigh. The first site visit is free.
What does a two-storey extension cost in Southend-on-Sea?
Using our East of England guide, a two-storey rear extension with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) is about £57,500–£78,000 including VAT. An extension over a garage is about £32,500–£47,500.
Which other places near Southend-on-Sea do you cover?
Everywhere around it, including Rochford (3.1 miles), Hadleigh (4.6 miles) and Rayleigh (5.8 miles), and the rest of Essex.