London’s best known professional kitchen extension team!

It is true the kitchen is the heart of the home, and when you take a look at our large, bright kitchen extension projects, you can see their appeal.

Kitchen extensions are built primarily to facilitate the installation of a brand new, larger kitchen. These are most commonly side return extensions, side extensions or rear extensions. The most suitable extension for your home will very much depend on the type of property that you own. If there is a house on your road that already has a kitchen extension, then you can get a fair idea of what you are to expect, and it is quite that your plans will pass planning.

Whether you can go higher, lower or further.  APT can help you realise your dreams.

Design & Build Basement Conversion in London

We are London’s top Design & Build kitchen extension company in London specialising in Design, Excavation, Construction. We can accommodate any basement build or conversion requirement in South West London.

Types of Kitchen Extension

wraparound-kitchen extensionWrap Around Kitchen Extension

A wrap-around kitchen extension is a rear extension combined with a side return extension.  The wrap around extension provides maximum space and dramatically alters the ambience and shape of your house.

If you want to achieve a bright airy open plan kitchen, a dining area & a social gathering space all in one area, then a wrap-around extension is the top option for you.

This style of open plan living has migrated over from the US and is becoming ever more popular here in the UK.

We have witnessed this type of space working well for growing families.

rear-kitchen extensionKitchen Rear Extension

Rear extensions extend out from the back of the property into the garden space. Full width rear extensions are typically carried out on properties where there is no side return or the property is semi / fully detached. They most commonly extend from 4  to 10 meters in length from the rear of the house for the full width of the house. These projects often significantly increase the ‘meter sq’ area of the kitchen.

A rear extension is the ideal option to go for if you spend a lot of time in the kitchen. Most often these kind of kitchens are big enough  to accommodate island units. Large rear kitchen extensions are not only good for large families, but they are also perfect for those that love to entertain in outdoor space.

Typically, these kind of renovation styles are separated into three areas – the kitchen, the dining area and the seating area – so that when your entertaining, your guests can mingle & choose which part of the room they want to reside.

Uncover more space in the rear of your house.

Discover a new dimension beneath your feet.

Quick Easy Design & Build Kitchen Solution

The majority of our kitchen extensions are large and regularly feature island units.

APT Renovation can take care of all aspects of your bespoke kitchen extension project. We can generate designs and measurements of your project, then subsequently keep the ball rolling whilst guiding you though the whole process. If you don’t already have an architect, we will start off by submitting your project to planning permission, passing the building regs, and navigating the highly restricted building control process.

We have a history of creating exceptional residential extension. We are highly skilled combining clients’ ideas with our expertise in the construction of bespoke ground rooms and cellars. Our in-house team of architectural designers and structural engineers can create or transform any space for you.

We are also able to work on larger projects, like “mega basements” and “super substructures”, as well as large entertainment rooms, home cinemas, gyms, interactive children’s playrooms, study rooms, swimming pools and ground floor spa spaces.

Why Choose us for your Kitchen Construction Work.

Our in-house team of qualified residential Kitchen Extension Architects are capable of undertaking any project. All projects are bespoke and honed upon the clients request,

Our first step towards building your project will be to arrange a free site visit to your home. We will discuss your ideas for a basement or cellar conversion, and create a design brief. This brief defines our objectives. Using our extensive knowledge and experience, we will advise you where the design might need to be altered, in order to maximise the proposed changes, and we will strive to exceed your expectations.


light up your garden
Maximise the liveable space in your rear garden

Once you have approved the initial design, APT Renovation can take care of all the necessary plans etc., submitting the basement or cellar designs as part of the planning application. We can also deal with all issues relating to party walls, when required, and to the Building Control process.

We will act as your agent, so you really only need to pay the required fees and wait for the decision. We ensure that the designs that are submitted for the planning application are sound from the construction point of view, and that they do not imply any fundamental design modifications.


Renovate and Extend your Kitchen

We work with RIBA Chartered Architects that are specialised on residential builds who collaborate with the on site building specialists to create the space that you desire.

Discover a new dimension beneath your feet.

Who we are

Our Design & Build services will be tailor-made to your personal needs, and the project will be delivered and managed by our team of:

• Project managers

• Architectural Designers

• Design consultants

• Quantity Surveyors

• Structural Engineers

• Professional Builders

We take care of everything

APT Renovation offers a full Design & Build service:

• Architectural Drawings

• Planning applications

• Building Control

• Project cost estimation

• Detailed architectural CAD / 3D designs

• Construction

APT Renovation team are always happy to hear your thoughts about your project, either on the phone or in person.

If you’d like to know more please arrange a FREE no obligation site meeting you.

A Free, No Obligation Site Visit / Consultation

APT Renovation will arrange a site visit to your property, to discuss what you would like to create within your new or existing basement / cellar. We are happy to answer all of the important questions that you will have during our initial visit. APT Renovation offers a full service, which includes submitting detailed and comprehensive plans – or we would be happy to excavate and build your basement project from any existing plans that you may have. APT Renovation will send you a quotation within eight days.

basement conversion company design service

Design Service

If you require a Planning and Design service for your basement conversion project, our in-house Architectural Designers, substructure and groundwork Structural Engineer and Party Wall Surveyor are on hand to help you visualise your plans, and to discuss them with you to ensure that you are completely happy with the final design. Every process will be explained to you, from beginning to end. Our primary concern is making our clients happy.

basement conversion company

Health and Safety at every stage

Health & Safety is of the utmost importance on every site on which we work. This is something that concerns all of our staff members, but also everyone else in the vicinity of the works, including you, your neighbours and even passers-by. Due to the nature of our work, there is always the risk of injury, or even death, as ladders, tools and various materials can be hazardous. Basement conversions, in particular, are technically very challenging, and can pose a number of different risks, with a large proportion of such projects in London regularly failing safety checks. Unguarded excavations and unprotected floor openings can represent a serious danger to all concerned. That is why our staff are expertly trained and will always diligently adhere to all necessary Health & Safety procedures and issues.

basement conversion british standard

British Standard 8102:2009

British Standard 8102:2009 is the Code of practice for protection of below ground structures against water from the ground. In essence, it is the primary design guide for structural waterproofing and groundworks in the UK, with a recent update having been released in November 2009. This document should cover every consideration relating to waterproofing design.. If you have further questions in regard to BS 8102:2009, please feel free to contact us.

basement conversion specialists


An intuitive basement construction process will ensure that your project runs smoothly. It will be monitored and overseen by our Managing Director, Andi Pepaj, and managed by our Project Managers on site.
APT Renovation has over 17 years’ experience in underpinning and basement excavation, creating basement conversions to a very high standard.
Your Project Manager will be on site all day, every day, and will be your first point of contact.

basement conversion tanking and excavation

Basement Tanking

Tanking, or ‘Type A barrier protection’ (a BS 8102 definition), is a specific form of waterproofing for underground rooms and under-structures, although it is a common term applied to all forms of waterproofing. In the true sense of the word, tanking means blocking water out of a structure by employing a barrier product which is installed internally, sandwiched within, or applied externally to, a structure. ‘Tanking’ is still widely used and applied in the building industry, but has declined in popularity in recent years, where retrofit protection is required for existing basements.

basement conversion waterproofing


Waterproofing is a very important aspect of basement and cellar conversion, particularly as the UK experiences a very high level of rainfall each year. A lack of waterproofing will eventually result in damp on walls, which does not have an attractive appearance. Furthermore, the resulting odours can be detrimental to hygiene, and can cause significant damage to paintwork and plaster. Worse still, damp can lead to breathing problems and other health issues, so it is something that should be eradicated immediately.
APT Renovation Design & Build has had huge success over the years in waterproofing with Delta Membrane Systems and pumps. For basement waterproofing, the Delta sealed system ensures that all membranes are expertly sealed and secured, as well as any protrusions or crevices. Delta Systems are incredibly effective in dealing with adverse water conditions, especially in basements that have a propensity to flood. There is a 30-year guarantee on all Delta membrane systems

Visit the Delta website

basement conversion company


Our construction team is ready to make the underground rooms or space in your basement that you have been dreaming of come to life. Our dedicated and experienced tradesmen will work tirelessly to complete your project on time, with no stone left unturned. Our aim is for you to be completely happy with the work, and we will only sign off the project once we have your consent to do so.

loft conversion insurance cover policy

Insurance and Guarantees

APT Renovation holds public liability insurance, and an all-risks cover, to protect you and our builders. APT Renovation Ltd offers a 15-year warranty on all structural work.
With hundreds of basement and cellar extension projects completed to date, APT Renovation has an outstanding reputation for being basement conversion specialists, dedicated to creating state of the art spaces, with immaculate attention to detail.


A Building Inspector will visit at regular stages throughout the project, to make sure that we are adhering to all the latest substructure and groundwork building regulations. Upon completion of works, the Building Inspector will make a final visit and you will be issued with a Completion Certificate.

Upon final completion you project you will receive following documentation where applicable:

Gas Safety Certificate, Electrical Sign Off Certificate, Drainage Layout, Plans as Built Drawings, Manufacturers’ Instructions For Appliances, Manufacturers’ Guarantees For Appliances, 10-Year Structural Guarantee