Side Return Extension

Side Return Extension

Side Return Extension

Side Return Extension About us

Homeowners in and around London want to maximise every last corner of their investment. With building and heritage restrictions tight around the capital, finding space to expand is a challenge. But of all the ways to enlarge the footprint of a house, none delivers more function per square metre than the side-return extension. Opening up a kitchen or lounge to the side threshold, incorporating space and natural light into the floor plan, can change the entire focus of a home. This minor shift makes a huge difference to a family’s closeness, productiveness and lifestyle.

Our London practice is founded on period home extensions, going back more than a decade. Our creative solutions to city living enhance the effectiveness and flow of the most frequented, hardest working spaces in a home. Our portfolio of side-return extensions reveals our passion for functional luxury, smart storage and spaces that breathe.

Collaboration is the cornerstone of our practice. Since we founded Scenario in 2007, we’ve used our knowhow, our compassion and our technological skills to create houses with a past, present and future. Scenario homes are tailor made to the needs of each of our clients, and every finished project tells their story – not ours.

To see what we mean, take a look at our landmark residential project Scenario House, located in Stoke Newington, East London. This widely recognised Victorian terrace-house expansion showcases the potential of a Victorian side-return extension. Still as fresh and efficient today as when we put it to paper, it merges contemporary steel and glass with reclaimed wood, antique brick and eco-friendly elements.

Side Return Extension Your Side Return Extension project

We’ve compiled some general research for homeowners thinking about extending into their home’s side return, or undertaking any additional residential renovations or expansions. Click here to read our illustrated overview, outlining each stage of the process. Keep in mind that most of these architecture projects require planning permission from the local council. We’ve built a successful record securing planning permission for our clients and claim home advantage across the city.

To help you determine the requirements for securing planning permission for a side-return extension, we’ve created this step-by-step guide. Download it below.


To discover whether or not your architect has had success steering planning applications through your local council, visit the “planning applications” page of your local council’s website and enter the architect’s name in the search criteria.

Side Return Extension

Side Return Extension

Scenario is an established architecture practice focusing on contemporary residential design. We take on projects of every scale and scope, from home refurbishment, renovation and expansions to new-builds.

Side Return Extension Working with Scenario Architecture

Scenario is a boutique architecture studio based in London, focusing on residential extensions, new-builds and renovations. Our bespoke service tackles high-end projects of every scale and scope, making city-living more accessible, comfortable and enjoyable long term.

We work closely with all our clients through every stage of every project, consulting regularly from the drafting phase through moving day. We work on site with contractors and builders with the goal that all our projects finish on time and on budget.

We pride ourselves on adopting cutting-edge architectural technology as soon as it’s available. Our experience shows that real-time visualisations are the most efficient tools for choosing fixtures and fittings, and for simulating natural light, so state-of-the-art 3D design and visualisation tools are standard on all our projects.

We produce reliable construction information ahead of breaking ground with 3D building information modelling (BIM) technology. All our project data derives from accurate, coordinated 3D models, and saves our clients time, money and worry. The Chartered Institute of Building (CIOB) has published this case study featuring a Scenario Architecture project. It demonstrates the benefits of advanced technology for domestic architecture.

Scenario is a RIBA Chartered Practice complying with the strict criteria of the Royal Institute of Chartered Architects. Our relationship with RIBA helps to protect our clients against health and safety issues with quality-management systems.

Side Return Extension

Side Return Extension In our client's words

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Side Return Extension Further Reading

The housing market in Britain’s southeast is hot. Trading up to accommodate a growing family is particularly daunting, and in many areas in and around London the saying “Don’t Move, Improve” has caught on. Recouping space from a house’s side return – the empty void at the rear that separates the kitchens and gardens and many attached terrace homes – is particularly common. With this option available to most Victorian homeowners comes the ability to plumb new areas of the home. Small period kitchens can open up into the side return of an attached house without eradicating the period look of the place. And in the recovered space, a corner can be reserved for a small guest toilet or utility room. In some neighbourhoods around London, side-return extensions are grouped under “permitted development”, which means they don’t require planning permission from the local council if the final plans heed the extended volume requirements of the area. Avoiding time-consuming planning applications will save you money in the short run.

Extending your house only a few metres can open up any space in a dramatic way – particularly if you find an architect whose drawings integrate the adjoining rooms. A side-return extension can turn several poky rooms into a so-called Great Room in just a few months. It can enable a family to include a kitchen island or peninsula in their plan where, previously, counter space was at a premium. Where once cupboards and uppers crowded the room, a good side-return extension can deliver clean, uncluttered walls hung instead with art. In a typical Victorian terraced house – still the most common style of family home, at least in London – a side-return extension has the greatest potential for transformation for the price.

Many Victorian homes – particularly in London and some of the market towns within the Home Counties – sit in conservation areas with strict planning regulations. Applying for a side-return extension in one of these areas should be fairly straightforward, as long as the project complies with vernacular elevations. Anyone seeking to undertake a side-return extension in one of these areas would be wise to hire an architect to help ease them through the planning process. On top of this, they will have to undertake a Building Regulations application to make sure your design complies with national standards in fire safety, ventilation, plumbing and structural integrity. Better architects have relationships with most building and planning commissions and will be able to tackle these responsibilities for their clients. If you’re interested in taking on a side-return extension, contact your preferred architect or visit the Projects page of this website for more information.

Side Return Extension Frequently Asked Questions

    There is no doubt that choosing an architect is a big decision and there’s a huge amount of information to consider. As you may have already experienced, different firms and architectural practices across London tend to differ in terms of the language they use, which aspects they emphasise and in their fees and scope structures. We have compiled an essential guide to choosing an architect, which includes the three most important considerations to have on your list whilst you come to a decision. This guide is based on our fifteen years of experience as a top architectural practice in London and includes our expert recommendations to ensure you make the right choice and select the architect that is best suited to you and your project. Click here to read the full guide.

    Side Return Extension

    FAQHow should I decide which architect to work with?
    The scenario design process was developed, tested and perfected through over a decade of extensive delivery of residential projects within and around London, some of its key features are listed below:   
    • Scenario based design – We start each and every project with a meticulous analysis of our client’s vision, requirements and aspirations. We do this by asking our clients to imagine their everyday scenarios living in the completed house and describe their desired interaction with it. 
    We then translate the resulting high definition brief into an informative and revealing 3-dimensional simulation, illuminating aspirations, requirements and patterns of habitation. 
    • Uniquely interactive - Our client’s deep involvement in the process does not stop with completion of the brief. Our design meetings are highly interactive, informal and fun. 
    Sitting together in front of a real time 3D model of the proposed design with realistic materials, lighting and textures we push and pull the proposed scheme together to explore its full potential and drag and drop different materials to explore various options. hen we invite our clients to take a virtual reality tour through advanced equipment that is always available in our practice for our clients to explore their projects at different stages of development. 
    • Designed to reflect you – Based purely on your lifestyle, aspirations and requirements and free from externally imposed concepts, metaphors and pre-conceptions, a completely fresh and unique design will gradually emerge and it will tell your story not ours. 
    It will not look like an image cut out of a trendy architecture magazine and not designed to intentionally impress anyone. It will feel familiar, warm and inviting and you will recognise yourself in it because it will be a genuine expression of the unique way in which you and your family wish to interact with it and enjoy it for many years to come.

    Side Return Extension

    FAQWhat is unique about the Scenario design process?
    Any architectural project comprises three main aspects, Creative design, Technical design and Project Management. A successful architectural project can only be achieved when all three aspects are properly performed and harmoniously integrated by an experienced professional. But can we really except a single person to specialise and shine in all three aspects and furthermore skilfully negotiate and balance the often contradictory challenges these aspects present? The basic assumption underlying the common structure of almost all other architectural practices today is that it is possible and this is precisely what is expected from the lone and often junior Architect that would typically be assigned to run your project start to finish. Scenario works in a completely different and new way, we believe in specialism and teamwork and therefore assign three experienced specialists for each and every project. A project team in Scenario is composed of a Project Director, a Designer and a Technical Designer, seamlessly collaborating to deliver results, which are noticeably superior to anything that a single person, skilful as they may be, could ever produce.

    Side Return Extension

    FAQWho will be assigned to work on my project?
    A key aspect, absolutely necessary to ensure successful delivery of your project is appointing a suitable and competent professional team. If we work together on your project we would be appointed as your Architects and Lead Consultants and help you to assemble the rest of the professional team. Most projects in and around London will require at least four additional consultants, a Structural Engineer, a Quantity Surveyor for cost control, an Approved Inspector to ensure and certify compliance with building regulations and a Party Wall Surveyor if any work is to be done to a party wall or structure. For some projects, depending on scale, complexity and your specific aspirations it may be recommended/required to use the services of additional consultants. Including but not limited to: Planning, Heritage, Right of Light, Landscape Designer, Audio Visual and Building Services Engineer. When appropriate, we will discuss these options with you and obtain relevant quotes for all additional consultants for you to consider.

    Side Return Extension

    FAQWhich additional consultants are required for my project?
    Planning in the U.K in general and in Greater London in particular is admittedly a tricky business. It is a complex maze of policies, standards and regulations that requires specialised and up to date knowledge and skills to navigate successfully.  Over the years we developed a strong approach and an effective methodology, allowing us to maintain an outstanding track record stretching over more than a decade. Successfully securing planning permission for our clients across Greater London and the Home Counties.  The key aspects of our approach to planning are listed below: 
    • Collaborative – We start the conversation with planners early and advise most of our clients to seek pre-planning advice prior to submission of a full planning application. Our experience shows that when properly consulted and liaised with, most planning case officers will be receptive to conduct a professional dialogue, increasing chances of successes. 
    • Strategic – We tailor a custom planning strategy for each project based on its circumstances such as planning history, local context and specific challenging elements. We sometimes split applications or introduce minor tweaks to the scheme during the consideration period in conversation with the officers to prevent one contentious element from jeopardising approval of the main scheme.
    • Professional – Our experience shows that the quality and clarity of the submission in terms of background research, planning history of the property and context, precedent and of course the arguments presented to support the case has a tremendous effect on success rate. 

    Side Return Extension

    FAQWhat is Scenario’s approach to planning?
    The standard consideration period for a residential project is eight weeks, this is the official time frame for your local council to carry out consultation with the neighbours and reach a decision.  We recommend allowing for a minimum of ten weeks from submission to decision as in practice the process always takes slightly longer for the following reasons: 
    • The decision period clock only starts ticking once the application is validated by the Council, This requires then to check that the forms are completed correctly and that the submission contains all the necessary drawings, statements and reports.
    Validation can take anything from a few days to couple of weeks when the council is very busy, which is most of the time…
    • Although required by law to provide a decision within the statutory eight weeks period, it is not uncommon for councils to miss the deadline of the consideration period, normally only by a few days, sometimes longer. 
    While there are some effective measures to apply pressure, which we do not hesitate to use when appropriate, it is generally beneficial for the project to bear with the council a little longer. 
    • In some cases the council may ask us as your agent for an extension of time, this may be requested due to internal reasons or as an acceptable result of a professional discussion that we are conducting with them about certain aspects of the application that they are not sure about.

    Side Return Extension

    FAQHow long will it take to obtain planning permission for my project?
    Once we have an initial scheme designed for your project which you are happy to proceed with, we will advise whether we recommend obtaining pre-planning advice or proceeding directly to the submission of a full planning application. Most of our projects are submitted first to pre-planning when the following applies.
    • Our experience shows that planning officers respond better to projects when they feel consulted and collaborated with. We find that when we truly listen to their often helpful and valid feedback and treat them as consultants for the projects and not representative of an evil enforcing authority, they tend to collaborate well with us and demonstrate increased flexibility.
    • Although the council in theory have eight weeks to consider your application, in practice they are constantly overloaded. They will only look at your application in the last few days of the consideration period. If this is the first time that they come across a scheme that they were never consulted about, our chance to secure permission for you in a single attempt is significantly compromised.
    • The standard practice is for the council to consider the full planning application as submitted and then issue a yes or no decision. Case officers are not required or even encouraged to enter a discussion with us or accept resubmission of minor changes to the proposed scheme during the consideration period.
    In practice our established working relationships and long-standing experience working across Greater London and the Home Counties often enables us to have a meaningful discussion and even introduce minor tweaks to the submitted scheme within the consideration period and prevent the application from being rejected. The chances for this strategy to deliver the desired results increases significantly with projects which were submitted first for a pre-planning advice.

    Side Return Extension

    FAQWhat is pre-planning and will it be required for my project?
    In the past, it was common practice for local authorities to impose sustainability standards on residential developments. However, the 2015 Deregulation Act removed the obligation on local authorities to require any standard at all, which means the only requirements having fallen back to those of the Building Regulations.  With no clear and improved targets to work towards, in collaboration with Envision (, we have created optional Sustainability ‘Levels’ to offer our clients the chance to drastically improve the sustainability credentials of their home. These ‘Levels’ encompassing Bronze, Silver, Gold and Diamond, traverse a clear and applicable route from basic compliance with current Building Regulations all the way to the full and rigorous HQM (Home Quality Mark) certification within Level Diamond. As the packages become more elaborate in terms of sustainability, analysis and implemented measures, they provide increasing tangible benefits. Ranging from thermal and acoustic comfort and wellbeing, to reduced carbon foot print, savings on running costs and significant advantages through the planning process.  The more elaborate packages obviously entail higher cost in terms of professional fees as well as impact on the construction cost, although each sustainability ‘Level’ will endeavour to not overly burden the construction budget.

    Side Return Extension

    FAQWhat is Scenario’s approach to sustainability?
    In a nutshell building control is the means by which Local Authorities enforce compliance with current Building Regulations.  In practice there are two main ways to go about obtaining the required advice and certification for your project, via your Local Council’s Building Control Department or via direct appointment of an Approved Inspector who is authorised to carry out the inspection and certification on behalf of any local authority.   The role of either the Council’s Building Control Officer or an Approved Inspector is to verify that your project meets all current Building Regulations. They will review and approve all the drawings, inspect the actual work carried out on site and once the project is completed, issue the final compliance certificate. Due to an open market, healthy competition between local councils and approved inspectors, the process and associated costs are almost identical. Having said that, our experience is that the private inspectors still feel and behave more as your appointed consultants and the council’s service still feels more like a statutory inspection and it is often slower and less responsive.  While it is always good to be informed and understand the process well, as your appointed architects we will take care of this aspect of the project for you and save you considering comparable quotes that we will obtain on your behalf and appointing the selected provider. You can leave this aspect of your project entirely with us.  Building control is required for almost all projects, and for all the projects we ever worked on as only minor renovation works may be exempt.

    Side Return Extension

    FAQWhat is building control and is it required for my project?
    Currently we recommend allowing between £2,500 and £3,000 per square metre for side extensions, rear extensions or front extensions. For basement extensions, which are most expensive way to add space to your home, we recommend that you allow between £3,000 and £3,500 per square metre. When it comes to roof extensions, our experience shows that it is better to allow a lump sum of £40,000-£60,000 for loft conversions with dormer windows and between £80,000 and £120,000 for mansard roof extensions. These ranges are based on averages from numerous actual projects that we have completed in and around London since we established Scenario in 2007. We only use these rough costs per square metre during the early stages of design to maintain awareness of your target budget until a cost professional is appointed and more accurate methods of estimation are employed. The actual cost for your project will depend on many factors, including the complexity of the design, level of structural support required, and selection of fixtures, fittings material finishes. Using these rough ranges as a guide we will work together with you in an interactive process to optimise budget and scope and find the balance that works best for you. The estimated costs per square metre mentioned above are for the build costs only and exclude VAT and professional fees.

    Side Return Extension

    FAQWhat is the cost of building an extension?
    Currently we recommend allowing between £2,500 and £3,000 per square metre for areas which will undergo an extensive renovation. We designate an area of the project as extensive renovation if the planned works includes substantial changes to layouts, significant structural works, re-plumbing, re-wiring and full redecoration. For areas of lighter internal renovation which do not require significant changes to layout or substantial structural works but do require full redecoration, re-plumbing and rewiring, we recommend allowing between £2,000 and £2,500 as an estimated cost per square metre, we designate these areas as requiring medium renovation. If there areas in your project which only call for a light renovation such as re-plastering, and painting, installing new floor finishes and light modifications of electrics and plumbing fittings, we will designate these as areas of light renovation and recommend that you allow £1,500-£2,000 per square metre or even as low as between £1,000-£1,500 if you only have light touches in mind. The real cost for your project will depend on several different variables including the complexity of the design, extent of structural works and level of fixtures, fittings and material finishes. These estimated costs per square metre are for the build cost excluding VAT and professional fees.

    Side Return Extension

    FAQWhat is the cost of an internal refurbishment?
    If you are thinking about building a new house from scratch for which the term Self Build is often used, we currently recommend allowing between £2,500 and £3,500 per square metre for projects in and around London. This may sound like a very wide range initially, perhaps too wide to be useful? As soon as we can establish even a few of the basics of your requirements and aspirations for the project we can safely narrow it down and customise it to match your intentions. The key parameters that will help us to refine initial estimates are whether or not a basement is required to achieve your target floor area, the likely construction method and corresponding structural approach and of course your desired level of fixtures, fittings and material finishes. Another key parameter that we must consider right from the outset is the level of sustainability that we are aiming at, are you satisfied with the base line requirements as defined by current building regulations, or should we aim higher? Working together with sustainability experts we have created our own bespoke set of sustainability packages which allows you to place your sustainability target anywhere you wish. This can range from basic compliance to an extremely sustainable and energy efficient standard which comes with great savings on running costs, future proofing and wellbeing benefits such as improved air quality, thermal comfort, and considerate and healthier surface finishes.

    Side Return Extension

    FAQWhat is the cost of building a new house?
    The fee structure that we will offer will depend on the type and scale of your project as well as the scope required from us. The vast majority of the projects we take on are what we call ‘full projects’, these are projects for which we will provide full Architectural services from inception to completion, covering the standard scope of services offered by most RIBA Chartered Architects and more. For these full projects our fees will be calculated on the basis of an agreed percentage of the final cost of the building works exclusive of VAT and professional fees. At any given time, we will calculate our fees based on the latest construction cost estimates available until the final cost of the building works has been ascertained. Our fees will be adjusted both forward and retrospectively to reflect any increase in budget and scope of the project, and forward only (due to work already completed) to reflect any decrease in budget/scope. During early stages, our fees will be calculated based on our in-house estimation tool and once available, on estimates by the appointed Quantity Surveyor, followed by actual prices of returned tenders and finally, the contract sum reflecting any changes during construction. Under unusual circumstances we may agree to take on projects only up to a certain stage, for example up to planning, and sometimes from a certain stage if we are taking over from another Architect. For these ‘partial scope projects’ we will normally put forward a simple fixed lump sum proposal.

    Side Return Extension

    FAQWhat is the fee structure used by Scenario Architecture?

Side Return Extension Want more space? Adding a side extension could be the answer

A side return extension is when the house is going under development to make alterations and extend parts of the home. There are different types of house extensions available to choose from that allow for home improvement. It allows for people to get as creative as possible with their living environment and removes having to move houses. There are rules, regulations and restrictions that come with developments of side return extensions.

The planning would need to be done with certified professionals to ensure that the integrity of the area is respected and the renovations are done right with considerations to planning, design and construction. Expansion of small living spaces is made possible and it can add long-term value if done right and is considered. A side extension should make a notable and positive difference to the home by opening it up. With an extension or building insurance, you can ensure that there is protection against liabilities. This helps to reduce stress.

Permitted Development Involvement

The consent needed for certain side return extensions involves following the relevant planning development rules. When the magnitude of the project is not too big, and if neighbours have been consulted prior to submissions, the house extensions would then comply with the standards, where a lawful development certificate would be viable to apply for. This gives permission to continue with the project under national permitted development rights immediately after it has been issued. The requirements for permitted development involve a few factors.

The land and building type would need to be considered and understood. This would involve knowing the legality and restrictions of the area. In designated areas such as heritage sites or conservation areas, restrictions would be involved where article 4 may be issued. Article 4 directions remove or withdraw any permitted development rights. Flats, maisonettes and listed buildings may have development rights that would be similarly restricted or do not apply, however it can be noted that 500 square meters of office space can be rebuilt into homes if it falls under specific requirements and permitted development rights are approved.

Residential homes may gain approval for permitted rights for interior modelling, the roof that can include solar power and other house extensions. Requirements would involve needing materials that are like the rest of the house. The developments done on a single storey home can be extended up to 4 meters in height and a rear extension of up to 8 metres. Boundary limits and extensions have minimum requirements that should be consulted with the local planning authorities to ensure that permitted development can be followed.

Planning Permission Involvement

There needs to be adherence to all guidelines and regulations with a load of information when submitting your applications. There are many considerations and procedures to consider during the design phase to increase the likelihood of approval. It is recognised that in order to achieve early success; it is necessary to have a positive and professional attitude toward the planning process. As well as a collaborative experience with the planners.

It is essential to first guarantee that the drawings in the design phase are ready. The designs would need to be quite comprehensive, and if possible or desired in the relevant applications, a 3D model would be added for further guidance and evaluation. This is where interactions need to become notably collaborative with the fundamental planners, officers, and architects engaged, meaning that if risk assessments are supplied, they should be considered and the Local Development Frameworks followed. Likewise, all parties should be involved in discussions throughout the process by you or your architect.

Standards such as building regulations and possibly protected extension or building insurance must be followed. Building regulations compliance is achieved by submitting detailed design plans for a comprehensive plan application, which includes structural design standards. A full plan submission would be required depending on the scope of the project; otherwise, a building notice application would suffice, which would be reviewed by an inspector and the local authorities. If approved, it means that you comply with the building regulations.

Effects Of The Party Wall Agreement

The Party Wall Act was enacted in 1996 to avoid disputes between neighbours and neighbouring property owners. A party wall divides landowners along their relevant property borders. When building improvements or excavating beneath boundary lines, the statute requires that adjoining parties be considered. This ensures that your neighbour is notified in writing of the impending renovation plans beforehand.

The statute gives neighbours 14 days to challenge or agree with proposed plans, and if a proposal is not responded to, it becomes a dispute. The plans would have to be agreed on, and if not, a surveyor would draw out a party wall agreement. They may be entitled to take legal action if the prior warning was not supplied. The statute protects people from damage, loss, or infringement on their properties where you would then be liable to compensate them. The moral is that it is critical to minimise conflicts between you and your neighbours and to get their cooperation early on by carefully considering them when planning.

Value of Side Return Extensions

The building’s design should benefit you and your family. As previously indicated, a side return extension that is carefully built and planned may add significant intrinsic worth to the experience. The flow, character, and allure of how you want to add a modern twist with the help of the proper specialists in the development process should help provide value for you.

Within the living space, great ventilation and natural sunlight may be maximised and produced. It should clear out any superfluous space and make the room more spacious. The difficulties that are put forth may be used to drive for sustainability and distinctiveness while also allowing for possible camaraderie. If there is a rich history in the building, the constraint may be used as a guide to help create innovative, practical, and sustainable solutions.