Trusted London Builders
KT5 Construction are design-and-build London builders specialising in house extensions, loft conversions, full refurbishments and new builds across the capital.
With over 25 years’ experience in London and Surrey, we focus on three things: clear communication, tight cost control and high-quality finishes. From first ideas to handover, you deal with one team that manages design, permissions and construction under a single contract.
What We Do
Building Construction
New Builds, Extensions, Conversions, Renovations
General Building
Property Maintenance, Handyman Service, Decorating
Design
Planning, Design, Project Management, Quality Checking
Why Choose KT5 as Your London Builder?
There are plenty of builders in London. Our clients choose KT5 because we offer:
There are plenty of builders in London. Our clients choose KT5 because we offer:
- Design-and-build in one place – we coordinate design, planning, building control and construction.
- Realistic budgets & programmes– no made-up numbers; we give honest ranges and stick to them.
- Experienced project management– a dedicated contact who keeps you updated and solves problems early.
- Quality workmanship– professional trades, proper supervision and a focus on the finished detail.
- London know-how– we understand tight access, party walls, conservation areas and neighbours.
Comprehensive Building Services in London
House Extensions – Expand Your Living Space
If you’re searching for trusted extension builders in London, our team delivers kitchen extensions, side returns, loft conversions, and large-scale home expansions designed to blend seamlessly with your existing property.
Luxury Home Construction – Bespoke New Builds
As premier London builders, we specialise in high-end homes that reflect your unique style — whether you prefer ultra-modern architecture or timeless traditional design.
Home Renovations & Refurbishments
We transform properties with structural upgrades, smart layouts, and contemporary finishes, always guided by best practices set out by the Royal Institution of Chartered Surveyors (RICS).
Bespoke Kitchen & Bathroom Installations
Our design-led approach creates kitchens and bathrooms that add value and comfort, featuring premium finishes such as quartz, granite, and marble.
Commercial Construction in London
We deliver tailored solutions for businesses, including retail fit-outs, office refurbishments, and new commercial spaces — always aligned with UK building regulations from Planning Portal UK.
Client Testimonials
“You made it so simple” – Just wanted to say thank you for making what I thought would be a difficult process much easier than I had imagined.
Thank you for my brand new house! The refurbishment and attention to detail makes it feel like a brand new house, but without the expensive cost of moving.
Just wanted to thank you for the work carried out to my new bathroom, I will definitely be in touch shortly to talk about my proposed kitchen extension.
Our 4-Step Process – The KT5 Construction Way
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Consultation & Planning – Understanding your goals and vision
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Design & Approval – Architectural drawings and planning permissions secured
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Construction & Execution – Delivered with precision and care
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Quality Assurance – Final checks to guarantee the highest standards
Contact Us – Work with London’s Trusted Builders
As experienced London builders, we incorporate sustainability into every stage — from sourcing eco-friendly materials to implementing energy-saving features.
Ready to get started? Whether you’re planning a house extension, a full renovation, or a new build, KT5 Construction is here to help. Contact us today for a free consultation on planning, design, or structural drawings.
Frequently Asked Questios
How long does a typical house extension take?
Usually 8–16 weeks depending on project scope.
Do I need planning permission?
Many projects are covered under permitted development rights — we’ll confirm before work begins.
What areas do you cover?
We operate across London and surrounding areas.
What’s the cost of a renovation?
Every project is unique — we provide transparent, tailored quotes.
Are your projects sustainable?
Yes, we use eco-friendly materials and energy-efficient designs in line with UK Green Building Council guidelines.
Our Services
House Extensions
KT5 Construction provides professional house or Property Renovations Services in Ash, tailored to your unique needs. Whether you’re expanding your kitchen or creating an open-plan living area, we deliver high-quality results.
Kitchen Refurbishment
At KT5 Construction, we are specialists in kitchen refurbishment in Surrey and surrounding areas, delivering bespoke designs that enhance your living space and add value to your home.
Loft Conversions
At KT5 Construction, we specialise in creating stunning loft conversions in Surrey that add space, value, and style to your home. From dormer loft conversions to luxury loft designs, our expert team handles every detail with professionalism and precision.
Groundworks
At KT5 Construction, we pride ourselves on being the go-to groundwork Company in London, delivering top-quality services for residential and commercial projects.
Bathroom Design & Installation
Your bathroom should be more than just functional—it should reflect your personal style and offer a space to unwind. At KT5 Construction, we specialise in Surrey bathroom design and installation, delivering tailored solutions that blend elegance, practicality, and luxury.
Property Refurbishment
Our Ewell Road Surbiton Project showcases the full spectrum of our refurbishment expertise. By managing every detail, from architectural consultation to final finishes, KT5 ensures each element meets the highest standards.
New Build Homes
As a trusted New Build Builder in Surrey, KT5 Construction has been at the forefront of creating bespoke, high-quality homes designed to meet modern living standards.
Architecture & Design
Expert architectural planning & creative design solutions for residential and commercial projects in Surrey & London.
Contact Us
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