Basement Conversion Surrey
Add significant space and value beneath your property. Fully designed, managed, and built by a CIOB Chartered Construction Company – with every structural, planning, and build challenge handled from start to finish.
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CIOB Chartered Standards
Client-Side Project Management
One Point of Contact
You Shouldn’t Have To Stress During Your Basement Conversion
A basement conversion is one of the most valuable things you can do to a property. It adds usable square footage without touching your garden, your footprint, or your roofline.
But it’s also one of the most complex residential construction projects there is. Excavation. Underpinning. Waterproofing. Structural engineering. Drainage. Party wall implications. Building regulations.
That’s a lot of moving parts – and most of them are invisible once the project’s finished. Which means getting them wrong isn’t just disruptive. It’s expensive to fix.
Work With Us, And You Won’t
TDB Projects manages basement conversions as a single coordinated project.
Every technical challenge, every specialist trade, every compliance requirement – handled by one team under one point of contact.
Mark Howe MCIOB leads every basement project personally. As a Chartered Construction Manager with over 20 years of experience, he understands the structural, logistical, and regulatory complexity that comes with working below ground – and manages it so you don’t have to.
You get a clear timeline before work begins. You know what’s happening at each stage.
Specialist trades are selected, scheduled, and coordinated by us.
And because basement projects affect neighbouring properties, we manage party wall requirements alongside the build so nothing holds up your timeline.
The result is a finished basement delivered on time, on budget, and built to a standard you can trust for decades.
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“Every client deserves to know exactly where their project stands – and why. That’s not a promise. It’s how we operate.”
Mark Howe, CIOB Chartered Construction Director
Basement Conversion Services Across Surrey
Every basement is different – the ground conditions, the existing structure, the intended use. The project management standard stays the same.
Full Basement Excavations
New basement construction beneath existing properties – including excavation, underpinning, and full structural works. Managed from initial site assessment through to completed living space.
Existing Basement Conversions
Transforming existing cellars or below-ground spaces into fully usable rooms. Waterproofing, tanking, damp-proofing, insulation, and complete internal fit-out.
Waterproofing and Tanking
The most critical element of any basement project. We specify and manage waterproofing systems that protect your investment for the long term – not just pass building control on day one.
Structural Engineering Coordination
Every basement project requires detailed structural design. We coordinate with specialist engineers to ensure underpinning, retaining walls, and load-bearing elements are designed and built to the required standard.
Party Wall Management
Basement works almost always trigger party wall obligations. We handle notices, surveyor coordination, condition surveys, and award agreements so your project stays on schedule.
Planning and Building Regulations
We manage planning applications where required and ensure full building regulations compliance throughout – including structural sign-off, drainage, ventilation, and fire safety.
How Your Basement Conversion Project Will Work With Us
Three stages. One point of contact. A clear timeline from day one.
Tell Us About Your Plans
We assess your property, discuss what you want to achieve, and give honest advice on feasibility, budget, timeline, and any party wall implications. No obligation.
We Plan, Schedule, and Manage Everything
You get a clear project timeline with milestones before work begins. Structural engineers, waterproofing specialists, groundworkers, and fit-out trades – all selected, scheduled, and coordinated by us. You stay informed. We handle the complexity.
Your Basement, Delivered As Agreed
A fully finished space beneath your home – and every technical detail handled properly behind the scenes.
Why Surrey Homeowners Choose TDB Projects for Their Basement Conversion
A basement conversion is one of the most technically demanding projects a residential property can undergo.
It requires precise structural engineering, specialist waterproofing, careful coordination with neighbouring properties, and a project timeline that accounts for challenges you can’t always see until you’re below ground.
That level of complexity needs experienced project management – not just a good builder.
CIOB Chartered Construction Manager
20+ years of experience
Based in Oxshott, Surrey
Clear project timeline with milestones
One point of contact throughout
Full CDM compliance
Basement Conversions Across Surrey and South West London
Esher, Cobham, Oxshott, Weybridge, Leatherhead, Guildford, Kingston, Wimbledon, and surrounding areas.
Not sure if we cover your location? Get in touch – chances are we do.
Testimonial
Tom Michaels, Homeowner
Testimonial
Kim Rempe, Homeowner
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Chris Peters, Homeowner
Ready to Explore Your Basement Conversion?
Tell us about your property and what you want to achieve. We’ll assess feasibility, give honest advice, and take it from there.
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