House Extensions In Kensington
How much does a house extension cost in Kensington? Start with the build itself: a single-storey extension typically costs £1,500 to £2,500 per square metre, depending on glazing, roof design and the kitchen fit-out. A double-storey extension costs about 50% more for the same footprint, but doubles the floor area you gain. On top of that, allow 10 to 15% for contingency and add VAT at 20%. It is also worth knowing that kitchen extensions and extra bedrooms are the changes most likely to add value, which helps when deciding where the budget should go in a Kensington home.
Then there is planning. Kensington's period terraces mostly sit within conservation areas, so even a modest rear extension can need an application to the Royal Borough of Kensington and Chelsea. Where permitted development does apply, a single-storey rear extension on a terrace can usually reach 3 metres beyond the original rear wall. Lemon Tree Construction checks this first, prepares the drawings and submits any application on your behalf.
Party walls are almost always involved on a London terrace, so we serve the necessary notices to your neighbours before work begins and plan access and deliveries around the street. Side return and two-storey additions are more likely to need full consent, and we explain the options before you choose a design.
Our family-run, FMB-registered team travels in from Frimley and manages each Kensington extension from the survey through to building regulations sign-off and final finishes, keeping you informed at every stage.
Single-Storey Extensions
Create additional living space on one floor that seamlessly blends with your existing home, tailored to your design preferences.
Double-Storey Extensions
Create spacious, multi-level additions that provide extra living space, blending with your home’s design, increasing its value.
Wraparound Extensions
Combine side and rear extensions to create a spacious, versatile living area that maximises your home’s footprint.
Side and Rear Extentions
Extend both the side and the back of the property for a larger, more open floor plan or for adding extra rooms.
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Single-Storey Extensions In Kensington

At Lemon Tree Construction, we specialise in designing and building single-storey extensions that provide you with additional living space tailored to your needs. Whether you're looking to expand your kitchen, create an open-plan living area, or add a new room to suit your growing family, our single-storey extensions are a cost-effective and efficient way to enhance your home.
We work closely with you to create a design that complements your existing property, ensuring the extension blends seamlessly with the original architecture. Our experienced team manages every aspect of the project, from obtaining planning permissions and approvals to construction and final finishes, ensuring a smooth and hassle-free process.
Single-storey extensions are an excellent option for homeowners looking to increase floor space without the complexity of multi-storey additions. At Lemon Tree Construction, we pride ourselves on delivering high-quality craftsmanship and creating functional, beautiful spaces that enhance your lifestyle and add long-term value to your property.
Double-Storey Extensions In Kensington

At Lemon Tree Construction, we specialise in double-storey extensions that provide significant additional living space by expanding both the ground and upper floors of your home. Whether you're looking to create a larger kitchen, add extra bedrooms, or increase the overall functionality of your home, a double-storey extension offers a versatile solution that maximises your property’s potential.
Our team works closely with you to design a personalised extension that seamlessly integrates with your existing architecture while meeting your specific needs and budget. From planning and obtaining necessary permits to construction and final finishing, we manage every aspect of the project to ensure a smooth and stress-free experience.
Double-storey extensions not only enhance the usability of your home but also increase its value, making it a smart investment for the future. At Lemon Tree Construction, we are committed to delivering high-quality craftsmanship and creating beautiful, functional spaces that improve your home's layout and your everyday living experience.
Wraparound Extensions In Kensington

At Lemon Tree Construction, we specialise in wraparound extensions that combine both side and rear extensions to create a significant increase in living space. This type of extension wraps around two sides of your property, providing a versatile and spacious addition that can transform the layout and functionality of your home.
A wraparound extension is ideal for homeowners looking to create an open-plan living area, expand their kitchen, add extra rooms, or simply maximise the potential of their property. Our team will work closely with you to design and build an extension that blends seamlessly with your existing home, ensuring it complements both the architecture and style of your property.
From planning and design to construction and finishing, we handle every detail, including obtaining necessary planning permissions and ensuring compliance with building regulations. With a focus on quality craftsmanship and tailored solutions, our wraparound extensions provide the extra space you need while adding long-term value to your home.
Side and Rear Extensions In Kensington

At Lemon Tree Construction, we specialise in side and rear extensions that provide the perfect solution for homeowners looking to maximise space without moving. Our side and rear extension services are designed to expand your home by extending both the side and rear of your property, creating a seamless transition between new and existing spaces.
Whether you want to extend your kitchen, create a larger living area, or add an extra bedroom, we work with you to design a customised solution that suits your needs, lifestyle, and budget. Our team handles every aspect of the project, from planning permissions and architectural design to construction and finishing, ensuring a smooth and stress-free experience.
Side and rear extensions not only offer increased living space but also allow for creative, open-plan layouts that enhance the flow of your home. With a focus on quality craftsmanship and attention to detail, Lemon Tree Construction ensures your extension blends beautifully with your existing home while adding value and functionality.
