Expert Architects in London

We are specialists In House Extensions, Conversion and New Builds

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Extension Architecture is one of the leading Architecture & Planning Consultant practices in London. We are a small group of designers and thinkers who specialise in house extensions London, planning applicationsbuilding regulation drawings, loft conversions London and project management. If you are looking for a reliable architecture firm in London to take you from creative direction to the ground up, Extension Architecture is here to help!

Architects in London

What Services Do We Offer?

Because we have over 11 years of expertise and experience as one of the best architecture firms in London, our team of architects in London can deliver an extensive range of services. From a variety of house extensions, such as flat conversions and double and single storey extensions to new builds and commercial, our London architects team can work with any property type and help you to create your dream space. Our services even include loft conversions and basement extensions, as well as kitchen designs. Our London architects team can help you to transform your property into your ideal aesthetic! 

Our architects in London are always available if you have any questions you would like answered over the phone or via email. However, if you would like to discuss any enquiries in more depth in person, we are more than happy to arrange a consultation at our architect firm in London and meet you face to face. 

Explore Our Projects

Extension Architecture is a multidisciplinary group of London architects and designers who have completed thousands of planning applications throughout the United Kingdom. The practice was founded by director Youn–Ou Kim, and has been working with accomplished designers for over eleven years to produce innovative and exciting projects. Without a doubt, we are one of the best London architecture firms around.

Why Choose our Architects in London?

Our team of London architects and designers consist of highly talented creatives and technicians alike. We love a good challenge and never fail to design and deliver. From residential properties to cultural buildings and iconic commercial landmarks, our architects in London have experience suitable for projects of all descriptions.

Architects in London

Highly Experienced Architects In London

Our architectural design team comprises exceptionally talented creatives and skilled technicians. We thrive on challenges and consistently excel in both design and delivery. As one of the greatest architecture firms in London, our expertise ranges from residential properties to cultural landmarks and iconic commercial buildings. We possess the experience necessary for projects of any scale or description.

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Dedicated Planning Consultants

As far as London architecture firms go, we at Extension Architecture can provide a comprehensive range of expert planning consultancy services. After thousands of successful planning applications. The extensive planning knowledge and experience of our architecture firm in London will be able to guide you effortlessly through the intricacies of your London council’s planning and approval processes.

planning consultatnt

Expert Care and Management

Our team of designers, surveyors, technicians, planning officers and architects in London have seen it all before. We’re the leading residential architecture studio in the United Kingdom and one of the most experienced London architecture firms available, having worked with projects of all shapes and sizes. This means that we have helped thousands of people extend their properties up and down the county – all from under one roof!

Popular Questions, you may be interested in

If you are looking to complete a new build, change the use of your land or building, or want a house extension, you will need planning permission. A Planning Application includes details of your proposal which is then sent to the Local Planning Authority. LPAs will need to check you application and grant it so that you may start works. Quite simply, it is a way that your local council can check that the proposed development is designed with sensitivity to local guidelines and is suited to the relevant site, street, and area. If we did not have this system in place, we could find buildings that have no uniformity in their designs, form or function. This way, the United Kingdom which is rich in heritage can keep your home as part of its identity whilst allowing you to make exciting and necessary changes.

Local Planning Authorities are generally the local council borough and these LPAs will have guidelines and links to explain what are within your rights to make changes to your property. They are usually receptive to pre-applications, but three years ago, most of the London Boroughs have adopted a fee for their pre-application advice. It doesn’t matter if you’re doing a small single storey rear extension, a loft conversion, or a large new build – most LPAs take approximately 6 to 8 weeks to make a decision on your project. 

Single-Storey Rear Extensions: The good news is, if you live in a terraced or semi-detached house in 2020, Local Planning Authorities have relaxed the rules and allow for extensions to go to 6 meters . If you live in a detached house, single storey rear extensions can be up to 8 meters in depth. Just be aware that if your property type is a flat, maisonette or in a conservation area, then you will need full planning permission. 

Side Extensions: Side extensions fall under permitted developent if they do not extend more than half the width of the original house. You can extend a maximum of 3 meters as long as it is a single storey extension and does not extend pas the front elevation. 

Double-Storey Extension: As of October 2019, new rules are being phased in which will allow homeowners to build extensions onto detached homes without requiring planning permission, under the usual rules of permitted development. This will make adding a two-storey extension to your home no more complicated than having a loft conversion. This doesn’t mean that there is no paperwork involved in undertaking a two-storey extension, but it will make obtaining permission for the extension much simpler. 

Loft Extensions: Roof extensions/should be set back, as far as reasonably feasible by at least 20cm from the eaves, unless it is a hip or gable roof (measure the 20cm along the plane of the roof). The roof extension should not hang over the wall of the house. To be a Permitted Development any additional roof space created must not exceed these volume allowances: 40m3 on terraced or semi-detached houses, 50m3 on detached houses. 

If you believe that your property falls under permitted development, the best way to ensure a positive result is to consult the advice of London architects to ensure that your extension follows these rules which are applicable to all extensions: 

  1. Materials should match the existing house 
  2. No raised platforms, balconies, or terraces 
  3. Single storey extensions should not be more than 3 meters high 
  4. Must not be taller than the existing building 
  5. The extension should not take more than 50% of garden space 

          Permitted Development Rights are a set of policies which allow homeowners greater freedom to add value to their home whether it’s increasing your property price or simply to add floor space. By acting upon these rights you can extend your property to a certain degree, without the need for Full Planning Permission, which can be a more expensive and time-consuming process, as long as you comply with relevant rules. 

          This generally applies to the single-storey side or rear extensions, loft conversions, front porches, double storey extensions, outbuildings, solar panels, skylights of dormer windows and new windows or doors. However, even Permitted Development has its restrictions and does not cover double-storey extensions, larger loft conversions, flats or properties in conservation areas. Regardless, even if you meet all the requirements for Permitted Development, you will still need to submit your plans to council which they will need to check, and approve. 

          For a full planning application, you will need good knowledge of the local guidelines, an appropriate design and a full set of accurate architectural drawings. Another architect firm in London may only do drawings, instead of offering extensive planning advice and submitting your application on your behalf.  

          However, Planning Consultants have expert knowledge of regulations and can therefore play a vital role in obtaining permission for projects with complex needs, but where do both options leave you after your application has been granted…or refused? At Extension Architecture, we understand that planning and building involves a lot of head-scratching, that’s why we guide you through the whole process, every step of the way. Extension Architecture specialises in design AND planning consulting and do not charge for submission and liaison with the council. We design, submit planning applications, building regulations with our in-house engineer, construct with trusted builders and offer creative interiors with our very own kitchen range. Why bother with the hassle if we can do it all for you? 

          Building Regulation drawings and control are very important because they insure the safety of people in buildings. Building approval means that your building complies with the national set of standards to protect people’s health and safety in and around buildings. Some examples of what building regulations include are structural calculations, fire-safety, insulation, damp-proofing, foundations, heating, ventilation and accessibility. Once you have received planning permission, building regulation drawings will have to then be submitted and approved before you can start construction. Just remember, cow-boy builders are always risky business and Local authorities have power under the Building Act 1984 to enforce non-compliant building work altered or removed. 

          Whether you are considering an extension, a plot development or a conversion, we are here to assist you in gaining LPA approval, maximising the potential of your project which in turn increases the value of your home. At Extension Architecture we offer bespoke packages to suit your budget, ensuring you get the perfect solution for you.

          We always provide 2D architectural drawings which detail the design in question. In more complex cases, we can provide 3D visualisations to bring your concepts to life and accurately display the proposed works.

          A site assessment will be carried out, either in person or remotely, which will gather information on the existing site. After this, initial drawings are produced and options are discussed with our London architects, which leads to amended drawings being made until both parties are happy. At this stage, the application is submitted to the local authority.

          All you need to do is fill out our online form which provides us with more information about your project, this way we can get back to you with a more accurate quote. If you would prefer to speak to one of our planning consultants directly, you can call us on 0203 409 4215.

          Steph Fanizza, Architectural Design & Team Manager

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