Structural engineer in Surrey

Structural engineering in Surrey

Our main business is inside the M25 and the counties that ring it, and Surrey is where we work most outside London. Since 2019 we have completed 50 projects in the county, mostly in the north where it meets Hounslow, Kingston, Sutton and Croydon. Spelthorne accounts for the largest share, with jobs in Staines-upon-Thames, Ashford, Sunbury-on-Thames and Shepperton, followed by Epsom and Ewell, Elmbridge and the towns strung along the A3 and the M25.

A recent house in East Molesey (KT8) shows the typical scope. We designed structural alterations to rework its internal layout, together with a new rear extension and changes to the roof. We also cover Weybridge, Walton-on-Thames, Esher, Cobham, Leatherhead, Addlestone, Egham, Woking and the Banstead and Reigate area. You get a fixed fee in writing before anything starts, and our typical turnaround is 10 working days.

From Thames-side terraces to large Surrey villas

The older centres of Staines, Epsom and Leatherhead have Victorian and Edwardian terraces and semis, often with bay windows, shallow brick footings and rear outriggers. Railway suburbs spread out from them in the 1920s and 1930s, so much of Ashford, Sunbury, Ewell and Molesey is interwar semis with hipped roofs, with post-war estates and bungalows beyond.

Further out, Esher, Cobham, Oxshott and the private estates around Weybridge are known for large detached houses in big gardens, many rebuilt or heavily extended over the decades. These bring longer spans, open-plan ground floors and wide glazed openings, which usually call for a steel frame rather than a single beam.

Gravels by the river, clay and sand inland

Spelthorne, Molesey and Walton sit largely on Thames terrace gravels, which generally suit shallow foundations but can hold high groundwater, and parts lie in the Thames flood plain. Around Epsom, Ewell, Esher and Cobham, London Clay is common, and it shrinks and swells as it dries and wets. Toward Woking, Chertsey and Addlestone, sandy Bagshot Beds appear on higher ground.

Further south, the North Downs bring chalk around Banstead, Leatherhead and Reigate. On the clay, the mature oaks, poplars and willows in Surrey gardens are the main cause of seasonal movement, and our guide to clay, trees and foundations explains why extension footings near them often go deeper. Where flooding is a concern, the council may ask for a minor development flood risk assessment with the planning application.

Structural work we do across Surrey

Most Surrey instructions are for extending and opening up family houses: rear and side extensions, removing internal walls to create kitchen-diners, and loft conversions on interwar semis. Large detached homes bring bigger steel frames and multi-room remodels, as at East Molesey. We also inspect cracking for buyers and insurers, particularly on clay near trees.

• Rear and wraparound extensions on interwar semis
• Steel frames for open-plan remodels
• Hip-to-gable and dormer loft conversions
• Crack and subsidence inspections near trees
• Foundation design on clay and gravel sites
• Structural reports for house purchases

Towns we cover in Surrey

Spelthorne has given us the most Surrey projects, then Epsom and Ewell, then Elmbridge. We also travel along the M25 to Runnymede, Woking, Mole Valley, Reigate and Banstead and Tandridge. We work across the county, so ask if your town is missing.

• Staines-upon-Thames (TW18)
• Ashford (TW15)
• Sunbury-on-Thames (TW16)
• Shepperton (TW17)
• Epsom and Ewell (KT17, KT18, KT19)
• East and West Molesey (KT8)
• Weybridge and Walton-on-Thames (KT12, KT13)
• Esher and Cobham (KT10, KT11)
• Leatherhead (KT22)
• Egham, Addlestone and Woking (TW20, KT15, GU21, GU22)

Surrey councils, Green Belt and Building Control

Surrey County Council does not deal with house extensions. Planning and Building Control sit with the borough or district council, such as Spelthorne, Elmbridge, Epsom and Ewell, Runnymede, Woking, Mole Valley or Reigate and Banstead. Much of the land between the towns is Metropolitan Green Belt, and many village centres are conservation areas. Your council will confirm what applies to your property.

We send our calculations and drawings to Building Control and answer their queries. The party wall rules apply here just as in London.