Structural alterations cover work that changes how a building carries load: new openings, removed walls, altered floors and steelwork. We appoint a structural engineer, build to the calculations they issue, and coordinate the building control application and inspections. We are a contractor, not an engineering practice, a surveyor or an architect, and we never produce structural calculations. This page covers the planning framework in Chesham, the ground beneath the town, the flood policies that apply, and the paperwork that closes the job.
Three documents make up the plan an alteration is judged against
The adopted development plan for Chesham is the Chiltern Core Strategy of 2011 and the Chiltern District Local Plan of 1997, alongside the Chesham Neighbourhood Plan. The neighbourhood plan contains twelve policies, numbered CHESH1 to CHESH12. The proposed Chiltern and South Bucks Local Plan was withdrawn from its examination in 2021, and Buckinghamshire Council is preparing a new local plan running to 2045.
Buckinghamshire Council also adopted the Chesham Regeneration Strategy in 2024, and Policy CHESH2 of the neighbourhood plan requires town centre proposals to have full regard to it. Arguing a planning case is not our job. Knowing when a proposal needs a planning decision as well as a building regulations one is our job, because it changes the order the work has to run in.
The bedrock under Chesham is chalk, but not one chalk
On the higher ground east of Chesham towards Botley, and north west towards Chartridge Lane and Asheridge, the mapped bedrock changes to the Lewes Nodular Chalk Formation. The British Geological Survey describes it as hard to very hard nodular chalks and hardgrounds which resist scratching by finger nail, with regular seams of nodular flint. A thin band of the Chalk Rock Member is mapped at outcrop south and south east of the town centre.
The survey's onshore borehole index holds 82 borehole records within the built-up area of Chesham. The Lowndes Park borehole is logged at 18.9 metres depth into the Chalk Group. Two boreholes sunk at Sainsbury's on Elgiva Lane in 1998 each reached 65 metres and are logged against the same aquifer. Records like those are background, not a substitute for a trial hole at your own bearing point.
Flood policy in Chesham names two watercourses
Policy CHESH11 of the neighbourhood plan identifies land subject to fluvial Flood Zones 2 and 3, and names the River Chess and the Vale Brook as the sources of that flood risk. The same policy has the effect of treating areas of high surface water flood risk as equivalent to Flood Zone 3a for the sequential and exception tests. Policy CHESH7 records the Vale Brook as a main river, and asks proposals affecting it to maintain or improve that function with appropriate sustainable urban drainage.
The evidence cited behind that approach is the Chiltern Strategic Flood Risk Assessment Level 1 of 2018. The River Chess is a chalk stream that rises in the south east of the parish. Alluvium is mapped along the head of the Chess beside Lowndes Park, described as normally soft to firm consolidated, compressible silty clay. It can contain layers of silt, sand, peat and basal gravel. Lowering a floor near either watercourse is a drainage question before it is a structural one.
Commencement and completion are both defined, and the certificate needs both
For building work other than new build, Buckinghamshire Council treats work as having commenced when 15 per cent of the planned work has been completed. For building regulations applications received after 1 October 2023, the council cannot issue a completion certificate without a notification of completion form, and confirmation that the works satisfied that definition of commencement.
A completion certificate is the document a buyer's solicitor asks for years later. We make the application, give the notices, book the inspections and submit the completion notification, so the file closes when the work does.
- Lintel replacement and repair over failed openings
- Bressummer and bay window support to period frontages
- Structural surveys and engineer coordination
- Underpinning and foundation strengthening in sequenced bays
- Steel beam and RSJ installation
Why Choose GS Renovation in Chesham
Structural alterations can need two consents rather than one, and they are not obtained the same way. Planning and heritage questions are settled with Buckinghamshire Council before we price anything, while the building regulations side runs alongside the works. We appoint the structural engineer, build to their calculations, and never produce calculations ourselves. Because a completion certificate now depends on both a commencement position and a notification of completion form, we handle both ends of that paperwork rather than leaving it with you. Building control applications and inspections are coordinated as part of the job. GS Renovation Ltd is registered in England, company number 14611254, fully insured, and quotations are free and without obligation.
- Registered in England, Companies House no. 14611254
- We build to the party wall award the surveyors agree, to the letter
- Honest updates if a date or a detail has to move
- Underpinning carried out in sequenced bays, never one long trench
- Photographs kept at each stage for your records
- Founder-led team with 30+ years of hands-on experience