EXTENSIONS & CONVERSIONS
House Extensions
Creating more space and value through expertly designed and built single and double storey house extensions across the UK.
About our house extensions service
House extensions are a practical way to transform a property, providing the additional floor space required for modern living without the upheaval of moving. At Design N Build, we specialise in delivering high quality extensions that integrate with your existing home. Whether you need a side extension to enlarge a narrow kitchen or a substantial double storey extension to add extra bedrooms, our team manages every stage. We work with residential homeowners looking to expand their living areas and commercial property owners seeking to increase the footprint of their assets. Our approach covers everything from the initial footings and structural steelwork to the final internal finishes. By considering the architectural style of your original building, we ensure the new addition feels like a natural part of the structure. From rear extensions that open up your home to the garden to complex wrap around projects, we provide the technical expertise needed to navigate planning and building regulations effectively.
What's included
- Architectural Design
We create detailed plans that maximise your available space while ensuring the design complements the existing aesthetic of your property.
- Structural Calculations
Essential for every extension, our engineers provide the calculations for foundations and steelwork, ensuring the new structure is perfectly supported.
- Full Shell Construction
Our experienced construction team manages the entire build on-site, including masonry, carpentry, roofing, and professional site management.
- Internal Fit Out
We handle all internal work, including partition walls, insulation, plastering, and the integration of M&E services like heating and lighting.
- Regulatory Management
Navigation of the legal requirements, from submitting planning applications to coordinating with building control officers for inspections.
Key benefits
- Functional Space Creation
Custom extensions allow you to create specific zones for work, play, or relaxation without the stress of moving house or paying relocation taxes.
- Property Value Enhancement
By adding high quality square footage and modern living areas, you can significantly increase the market valuation of your property for future resale.
- Better Thermal Performance
Modern extensions use the latest insulation and glazing standards, often making the new space more thermally efficient than the original parts of the house.
- Long Term Practicality Space
Adding a double storey extension provides the room needed for growing families, including extra bedrooms or en suites, without sacrificing your garden.
- Improved Internal Layout
We handle the integration of the new structure with your current home, ensuring the layout flows naturally and feels like a cohesive part of the building.
Project types we cover
- Single Storey Extensions
- Double Storey Extensions
- Rear Extensions
- Side Extensions
- Wrap Around Extensions
- Kitchen Extensions
- Commercial Extensions
Our process
- 1Initial Consultation
We discuss your goals, budget, and site constraints to determine the best type of extension for your needs and local area.
- 2Design and Planning
Our team develops architectural drawings and handles planning applications or Permitted Development enquiries with your local council.
- 3Structural Engineering
Specialist engineers calculate the necessary structural supports, such as steel beams and foundations, to ensure your house remains safe and stable.
- 4The Build Phase
Our builders manage the site, handling everything from groundworks and brickwork to roofing, windows, and internal electrics and plumbing.
- 5Finishing and Handover
We finish the interior to your specifications, followed by a final inspection to secure building regulations sign-off and project handover.
Why choose Design N Build Construction Company
- End-to-End Management
We provide a complete service from the first drawing to the final coat of paint, reducing the stress of managing multiple contractors.
- Quality Craftsmanship
Our focus is on durable construction and precise finishes, ensuring your extension stands the test of time and adds genuine value.
- Transparent Communication
We provide clear, truthful advice about what is possible on your budget and within local planning constraints, avoiding false promises.
- Technical Expertise贯
Our team has extensive experience in various extension types, from simple side builds to complex double storey renovations.
- Reliable Compliance建设
We prioritise safety and building regulation compliance, ensuring every project is fully insured and legally sound for your peace of mind.
Frequently asked questions
Do I always need planning permission for an extension?
Many single storey extensions fall under Permitted Development rights, meaning full planning permission is not always required. However, double storey extensions and projects in conservation areas usually need formal approval. We assess your specific project against local authority requirements to ensure every build is compliant from the start.
How long does a typical house extension take to build?
A simple rear extension might take 10 to 14 weeks, while a large double storey or wrap around extension can take 6 months or more. This includes structural work, roofing, and internal finishes. We provide a detailed schedule once the architectural drawings and structural calculations are finalised.
Can you handle both the design and the construction?
Yes, we manage the entire project from initial architectural design and planning applications to structural engineering, construction, and final sign-off. This integrated approach ensures that the design is technically feasible and stays within your budget constraints. Balancing aesthetics with site-specific structural needs is part of our core service.
How much does a house extension typically cost?
The cost depends on the floor area, the number of storeys, and the specification of finishes. For example, a kitchen extension with large glass bifolds will cost more than a standard side extension used for storage. We provide transparent, itemised quotes after reviewing your plans to prevent unexpected budget increases mid-build.
Are the works covered by building regulations and warranties?
All our extensions are built to meet or exceed current UK Building Regulations. This covers everything from structural integrity and fire safety to ventilation and insulation. Upon completion, you will receive a building regulations completion certificate, which is essential if you ever choose to sell your property.
Talk to us about your project
Expanding your home is a significant investment that requires careful planning and expert execution. Whether you are considering a modest side extension or a substantial double storey project, our team provides the technical knowledge and construction skills to bring your vision to life. We work across the UK, helping homeowners navigate the complex requirements of planning permission and building regulations. To discuss your project requirements or to request a detailed site survey, please contact our team today. We can provide a comprehensive breakdown of costs and timelines, ensuring your home extension project starts on a solid foundation and meets your expectations for quality and finish.
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