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SAP Assessments for Extensions and Conversions

L1B SAP Calculations London

Fast, fixed-price L1B SAP Calculations for London projects, bundled with the other approvals, calculations and tests your site needs. We've quoted on 220+ projects in the London area since 2021.

Part L1B Compliance Assessments for work to existing dwellings
Extensions & Conversions Support for a wide range of residential projects
Design Advice Practical recommendations where improvements are needed
Building Control Reports Clear documentation ready for submission

Trusted across London and the South East and the UK

  • 3,200+projects quoted through our portal since 2021
  • 5,000+individual services requested by developers and builders
  • 110+UK postcode areas covered, London and the South East included
  • 15+years of construction industry experience

Also most requested in London: Private Building Control10 Year Structural WarrantySAP CalculationsExtract Ventilation Testing

L1B SAP Calculations in London

Local L1B SAP Calculations for London sites

We handle L1B SAP Calculations for house builders, developers and self-builders across London and the surrounding area, covering postcode areas E, EC, N, NW, SE, SW, W and WC, plus outer London. That includes Croydon, Barnet, Ealing, Bromley, Enfield, Harrow, Hounslow and Kingston upon Thames.

  • Croydon
  • Barnet
  • Ealing
  • Bromley
  • Enfield
  • Harrow
  • Hounslow
  • Kingston upon Thames

L1B SAP Calculations in London: common questions

Do you provide L1B SAP Calculations in London?

We do. Send us the London site address and your drawings and we'll come back with a fixed price for L1B SAP Calculations, handled by our team from start to finish.

Which areas around London do you cover?

All of London (postcode areas E, EC, N, NW, SE, SW, W and WC, plus outer London), including Croydon, Barnet, Ealing, Bromley, Enfield, Harrow, Hounslow and Kingston upon Thames. We also work nationwide.

Can you combine L1B SAP Calculations with other services on my London project?

Yes. Most clients book several services together, such as Building Control, SAP, warranty and testing. You get one quote, one point of contact and a bundle discount.

Which councils around London do you work with?

We work on sites across the 32 London boroughs, the City of London Corporation and nearby Hertfordshire, Essex, Kent and Surrey councils, and coordinate with whichever planning and Building Control body covers your site.

Have you worked on projects near London?

Yes. Recent projects in the area include High Street, Fleetwood close, Holtwhites Hill. You can see more in our projects portfolio.

What do you need from me to quote for L1B SAP Calculations in London?

The site address and postcode, your drawings (plans, elevations and sections) and anything you already have from planning or Building Control. We'll confirm a fixed price and timescale for your London project.

Building in London

The London development market

London projects are dominated by flats: conversions of houses and commercial buildings, infill and backland sites, and mid-rise blocks. Tight sites, party walls, overheating risk and London Plan energy policies all shape what is needed, and boroughs set their own planning conditions, so the paperwork varies from one borough to the next.

Typical London projects we support

  • House-to-flat conversions
  • Commercial-to-residential conversions above shops
  • Backland and infill sites
  • Mid-rise apartment blocks and roof extensions

Councils we work across

We handle L1B SAP Calculations for sites in the 32 London boroughs, the City of London Corporation and nearby Hertfordshire, Essex, Kent and Surrey councils, and coordinate with whichever planning and Building Control body covers your site.

How L1B SAP Calculations works, what we need from you and full FAQs

L1B SAP Calculations Across London and Greater London

We support projects throughout Central London, Westminster, Kensington, Chelsea, Camden, Islington, Southwark, Lambeth, Greenwich, Stratford, Wimbledon and Ealing.

Nearby coverage also includes Croydon, Bromley, Barnet, Enfield, Harrow, Hounslow, Romford and surrounding Greater London areas.

Request Your Free L1B SAP Calculations Quote

Complete the form below with the London project address and description of works. Upload the existing and proposed drawings, construction details and available heating and ventilation information so our team can review the requirement and provide an appropriate quotation.






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