Double Storey Extension
Double Storey Extension
Scenario Architecture is a London-based practice founded on home extensions and renovations. Our creative solutions to the space constraints of urban living transform period homes into luxurious, hard-working spaces with smart storage and fluid layouts.
Our portfolio tends toward the high end of the market, yet we know all homeowners have concerns about extension costs. Scenario works with top architects, builders and cutting-edge technology to tap the potential of every home we approach, creating luxury – and the luxury of space – at competitive prices.
At Scenario, our architects take communication seriously. Good communication and the technical knowhow to efficiently carry out our clients’ wishes are what keep costs in check. When we design a loft extension, basement, side return or rear extension, we make sure our clients have control over every decision and every material. Our client-led process is what has made Scenario so successful since our first residential project in 2007. Scenario homes are tailor made to the needs of each of our clients, and every finished project tells their story – not ours.
Our landmark residential project Scenario House, located in Stoke Newington, East London, demonstrates the potential of a fully expanded and renovated Victorian home delivered on time and on budget for a growing family. Still as fresh and efficient today as when we put it to paper, it merges contemporary steel, glass, reclaimed wood, antique brick and eco-friendly elements that look extravagant but don’t cost the earth.
Double Storey Extension
Double Storey Extension
Your intention to extend your home
Starting a home extension in London
As a tool for homeowners thinking about extending into the loft, basement, garden or side return, we’ve compiled some handy research. Click here to read our illustrated overview, outlining the various stages. Remember: most residential architecture projects in and around London require planning permission from the local council. A good architecture practice will have built a successful record securing planning permission with various local councils.
To help you navigate the planning-permission process for any kind of home extension, we’ve created a step-by-step guide, which you can download below.
Tip
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.Double Storey Extension
Advice
We have created guides for homeowners to provide additional advice and help with your project. The following eBooks are currently available for you to download:1. Planning in London and the home counties - A guide for homeowners
2. Self build - A guide to building your own new build home
Double Storey Extension with Scenario Architecture
Working with Scenario Architecture to extend a house London
Our boutique architecture practice focuses on residential extensions, new-builds and renovations for budgets at the higher end. Our bespoke service tackles projects of every scale and scope, making city-living more accessible, comfortable and enjoyable for the future.
Our clients are kept in the know every step of the way. We consult with them regularly, from the drafting phase through moving day. In between, we work on site with all our contractors and builders with the goal that each project finishes on time and on budget.
Scenario architects adopt cutting-edge design technology as soon as it’s made available. In our experience, real-time visualisations are efficient, cost-saving tools when choosing fixtures and fittings and simulating natural light. State-of-the-art 3D design and visualisation tools are standard on all our projects.
Before breaking ground, we always produce reliable construction information with up-to-date 3D building information modelling (BIM) technology. We mine all our data from accurate 3D models to save our clients costs at every stage. The Chartered Institute of Building (CIOB) published this case study featuring a project in our portfolio. 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.
Double Storey Extension
Double Storey Extension
Double Storey Extension
Further Reading
So you’ve bought a home. In London and beyond, that’s a huge move. Nearly any property you purchase in Britain’s southeast will retain or accumulate value. When and if it turns out you need to grow your living space, you’ll want any enhancements you make to your home’s footprint to enhance the value of your asset, too. A good architect will factor in your home’s location, layout and structural integrity as well as the size of your family to make your desired project work for you and your budget. After all: house extension cost shouldn’t cancel out the benefits of a house extension.
It’s always difficult to project the cost of extending without evaluating the home itself, the homeowners and their plans. But it’s likely you can nearly double the size of your home’s original floor area at a fraction of the cost of the home’s value, even at upwards of £2,000 per square metre. Plus you will, of course, gain a nearly new living space without paying the stamp duty and agents’ fees associated with moving house – although you may need to purchase renovations insurance.
As with most construction, it is wise to source a few quotes for extending your house. With a range of budgets at hand, you’ll be able to assess which seem low, high and just about right, and choose accordingly. The foundation, walls and roof will suck up about 15 per cent of your costs, followed by Velux windows and rear glazing. You’ll want to price fixtures, fittings, appliances and any upgraded materials separately, so as not to be shocked when you receive your last invoice – new kitchens are particularly pricey, so keep your eyes out for deals and floor sales in the months leading up to a project.
In some neighbourhoods around London, home extensions are classified under “permitted development”, meaning they don’t require planning permission from the council in question 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.
Once you’ve agreed on a budget, set up a payment plan with your architect and builders that works for everyone. A great architect should be a problem-solver first and foremost: fitting the rhythm of your life into a physical shape and making sure every element of your home can be achieved structurally legally and financially. The professional you choose should create a bespoke space deeply attuned to your needs – not just today but in the future. He or she will be able to design special touches that make your life more efficient and pleasurable.
Less a costly investment or superfluous expense, a great architect is a value-adder, paying for him or herself over and over. Many homeowners, in an effort to cut costs, end up spending much more to fix the mistakes they make themselves or entrust to a layman.
In our clients words
Great ideas and vision to help with our substantial improvement of a Victorian terrace. In our experience Scenario's method prioritises the final result. That may mean more professional fees or higher quotes from contractors, as they understand the exact requirements.
Great, professional service. Good drawings and models and ultimately passed planning at the first attempt with Hackney Council. Would certainly recommend!
Scenario Architecture have created an outstanding design and space that was beyond my expectations. The design was through their unique process of understanding the client’s daily scenarios and collaborating with the client to come up with a unique design. The design process is one of the most memorable parts of the process and they also stretched my existing ideas to help create this unique space. A stress free journey throughout the whole process which Scenario were indispensable by giving advice on many difficult design and build decisions.
We wanted to renovate our house in a conservation area in central London. Given this involved a complete demolition and new build with an extra floor on top, getting planning approval was always going to be tricky. Scenario did an amazing job on the new house 'envelope' and throughout the planning phase. We couldn't have wished for better from them and having succeeded in gaining planning approval owe them a very big 'thank you'.
Scenario were great at thinking imaginatively and coming up with a design for a ground floor extension that was more ambitous than other architects we spoke to. They also helped us find a contractor who was able to complete the project working within timescale and our tight budget. I would recommend for mid to large sized projects with sufficient budget to allow for full utilisation of their creativity.ADVICE
FAQ
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.
- 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.
- 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.
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.
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.
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.
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.
- 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.
- 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.
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 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 (www.envisioneco.com), 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.
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.
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.
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.
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.
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.