Extending your home is a popular way to increase space and add value to your property. With the hassle and costs of moving house – from legal fees to stamp duty – the reasons to stay put and improve your existing home soon mount up.
But where do you start? We have compiled information about Home Extensions to help you make an informed decision.
Types of house extensions
There are few world-class cities where you can own your own house and convert it for your needs, and none as exciting as London. The city’s rich stock of residential housing has great potential for improvement. If you already own property in the capital and can’t justify the costs of moving house, renovating and extending your existing property may be the right move for you. Best of all, you’ll be able to stay in the neighbourhood you know and love.
Strict planning regulations in neighbourhoods rich with heritage housing make house extensions a challenge for some. Seeking the help of an architect, rather than going directly to a standard-issue builder or home-extension specialist, means the specific character of your home will be respected, enhanced and unnecessary additional costs avoided. An architect will unlock potential and use materials in an original way that can complement your home’s historic appeal.
Once you’ve found an architect whose style and personality balance your own, the process of transforming your home will fall into place. Together you can collaborate on tailoring the original bones to your personal lifestyle with detailed specifications, starting from the party walls inward. Even if planning regulations are stringent in your neighbourhood, you’ll usually be able to extend outwards at least enough for an extra room or two – taken from wasted outdoor space, eaves in a pitched roof or awkward corners you didn’t even know you had.
You could extend a kitchen to incorporate an eat-in breakfast room, add an en-suite bathroom, a bedroom for a new child or a home office. In a neighbourhood with newer housing stock, like a London suburb or brownfield development, more involved house extensions may be possible, like wraparounds incorporating a side return and rear, a second storey, garage topper or double-height rear extension.
House extensions are carried out in a more compassionate way today than they’ve ever been, and a good architect will strive to preserve original architectural elements – like decorative cornicing, ceiling roses, skirting boards, dado rails and picture rails – while giving your home the modern openness so many desire. Pivoting doors and Crittall-style steel windows are brilliant complements to period decorations and antique brick.
Once you’ve committed to the process, a house extension will make additional changes easier and less cumbersome, like new sash windows, flooring or a fresh paint job. They could be done concurrently with the structural work, pull everything together and help you get a good-as-new home that works with your unique way of life.
“Extending your garage is also going to be a great time to touch up the areas you may have been neglecting. If you’ve purchased your home and are upgrading, you may find that after years of abuse the garage isn’t in the state you’d quite like it to be. Take your time to not only plan your garage extension properly, but seal your concrete, paint the walls and even consider adding air conditioning to make it a liveable space” – Roy, Hack My Garage.
Links to articles about house extensions
Your house extension project
Scenario is a boutique architecture studio focused on improving homes with spacious, contemporary extension projects across London and beyond. Through our bespoke architecture service, we tackle projects of every scale and complexity, from modest single-storey extensions to side-return extensions project, basement extensions, loft extensions and rear house extensions project.
Our highly skilled architects can take you step-by-step through the challenge of building a house extension. We’ll collaborate closely with you from the initial drawings, detail design and planning, guiding you through the tender and construction process and completing your extension on time and on budget.
Early adopters of the latest drafting and building technologies, we use innovative 3D design and visualisation tools as a standard for all our house extensions. Our experience has shown that real-time visualisations and virtual reality are extremely efficient tools for choosing finishes, fixtures and fittings, and simulating natural light.
We use 3D building information modelling (BIM) to produce reliable construction information, so all our project data comes from an accurate 3D model. Using this technology collaboratively with consultants and contractors is proven to save our clients time and money. This Chartered Institute of Building case study featuring a Scenario project demonstrates the benefits of this advanced technology for house-extension projects.
Scenario Architecture is a RIBA Chartered Practice. We comply with all the criteria of the Royal Institute of Chartered Architects, covering insurance, health and safety and quality-management systems.
House Extension Costs
Nearly any property you purchase in the southeast will retain or accrue value. When and if it turns out you need more living space, you’ll want any enhancements you make to the size of your home to enhance your asset, too.
A good architect will factor in your home’s location, layout, structural integrity and the size of your family to make your project work for you and your budget. A house extension cost shouldn’t cancel out the benefits of a house extension.
Unless your investment is a purpose-built flat, you should be able to gain extra space that suits your lifestyle. If you own just part of a house, you can build up, down or out, depending on your specific location. If you own the entire house, chances are better you can add substantial square metres.
In some neighbourhoods around London, loft extensions and side-return extensions (recouping the side-rear void often left open between terraced houses) are grouped under “permitted development”, which means they sometimes 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.
On the topic of money: it’s always difficult to propose a house extension cost without evaluating the home in question, the resident family and their plans. But it’s likely you can nearly double the size of your home’s original square-metre floor area at a fraction of the cost of the original house. 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 building-related activity, it is wise to source three to five quotes for a house extension. With a range of budgets to hand, you’ll be able to assess which seem low, high and just about right, and choose accordingly. The foundation, walls and roof will soak up about 15% of your costs, followed by Velux 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 that last bill – new kitchens are particularly dear, so keep your eyes out for deals and floor sales in the months leading up to a project. Once you’ve agreed on a budget, set up a payment plan with your architect and builders that works for everyone.
The House Extension Cost varies and this will depend on the scale, design, exterior materials and interior finishes of your extension. Before designing an initial concept for our clients, we discuss their big-picture aspirations and daily requirements.
When we budget the House Extension Cost on any home, we must consider the different types of extensions projects. Extending upward with a loft extension, for example, is often significantly cheaper than a side-return extension and rear house extension and most definitely a basement extension.
We understand our clients’ desire to understand the cost of building an extension before committing to the process. For a single-storey extension – be it a side-return extension or rear house extension – we allow between £2,500 and £3,000 per square metre, depending on finishes. These figures can also apply to renovating the existing areas within a house.
Excavating a new basement is a great way to add significant floor space to your house with limited planning regulations. However the House Extension Cost per square metre is, by far, the highest in a basement. We allow between £3,000 and £3,500 per square metre, subject to finishes.
- As a dynamic practice operating in London’s premium residential market, managing projects remotely and conducting virtual meetings was a very familiar territory for us, long before the pandemic began and ‘working remotely’ became the norm.
- Our clients have very busy lifestyles and may move between several different locations, both within the UK and beyond, during the lifecycle of a typical project.
- To accommodate such client needs and enable us to run their projects smoothly we had all the technology and know-how associated with remote working in place for several years.
- Read our full (Virtual) Process
- 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.
- 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 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.
- 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.
House Extension Rules Made Permanent to Cut ‘Time-Consuming Red Tape’
The UK government has confirmed that house extensions’ rules will now be permanent to cut out ‘time-consuming red tape’. With this decision, homeowners should find it much easier and faster to extend their homes without having to jump through any unnecessary hoops.
Some rules of extending a house are:
- The extension should only be single storey
- The outcome should resemble the property
- The extension should be less than half the width of the original property
After the government declared that interim regulations would be made permanent, homeowners will continue building massive house additions without full planning approval.
Kit Malthouse, the housing minister, said the decision would allow people to expand their homes without dealing with ‘time-consuming red tape.’
‘By making this authorised development right permanent, families will be able to expand without having to relocate,’ he explained.
Since 2014, more than 110,000 extensions have been completed under the previously temporary regulations. According to the survey, a ‘reasonable’ price would be paid for prior permissions for house extensions, a type of light-touch planning application used for authorised construction.
This latest PD has brought mixed reactions from different people. Although, for example, Ben Edgley said that he understood the new changes were made with great intentions, there was a concern on the loss of control concerning the quality of design.
He further claimed, “PD conditions provide a clear framework for creating extensions, but skipping the planning process will affect the design leading to poor quality schemes.”
Even so, Eugene Kim, the managing director of London-based Extension Architecture, who has been filing about 300 planning applications for rear expansions every year, believes the regulation will speed up projects, noting that even basic applications take a long time to process.
‘You will find that over 70% of clients are unaware that a simple planning process takes three to four weeks to prepare and two weeks to validate,’ he added. The LPA then has eight or more weeks to make a decision.’
The allowed development right, according to Kim, will help harmonise methods across multiple planning authorities since different municipalities presently interpret standards differently.
While the change might get regarded as good, Darren Bray, director of Southampton-based Studio B.a.d Architects, believes it could lead to some bizarre, quirky, and plain crazy suggestions.’
‘Even when it comes to a minor home addition, I usually acquire chapter and verse from the local authorities. and even hire a planning consultant so that we can respond sympathetically and contextually.’
‘Over the last 25 years, the UK has gotten littered with UPVC conservatories, and I fear that we are seeing a systematic and formulaic reaction from prospective non-architects and firms offering a prefab type answer to this, rather than a design-led sensitive approach.’
According to the Local Government Association (LGA), permitted development laws are robbing local communities of their freedom to determine the environment in which they live.
‘While we recognise that building additions under allowed development have been popular with homeowners, the planning process exists for a purpose,’ said Councillor Martin Tett.
The new allowed development right was announced as part of a broader package of planning amendments that also included looser regulations for converting retail spaces into offices. It comes after a government survey on the proposed legislative change, which sought input on various initiatives, including rooftop expansions and, more controversially, the demolition of workplaces and their replacement with houses.
Although more than half of respondents were opposed to permitting rooftop additions without planning approval, the administration has said that the regulation would be implemented. Despite considerable resistance to plans to allow for the demolition of workplaces and their replacement with houses, the administration indicated it was still considering adopting the regulation.
The RIBA called the idea to demolish the offices “both shocking and perplexing,” saying, “We firmly believe that quantity cannot be accomplished at the price of quality.” Because of concerns about the quality of office-to-residential conversions, the government’s distribution of approved development rights has been heavily criticised. Most people are not with this idea thus the negative comments now and then.
In 2021, Labour vowed to close a loophole in the planning system that it claimed allowed developers to skirt affordable housing rules and build slum housing.’
How does the public take advantage of this opportunity? People who want to build a new house need more space but do not have the money. This is good because now people can go down their street and see if they know anybody that needs an extension done on their home or ask around in town, which will speed up projects. But, on the other hand, it might be not good because some people may not have the funds for this and may feel pressured into doing it.
It’s not great that these laws are stripping communities of their ability to determine what they want in a neighbourhood because there is no need for people to build on specific properties, making some parts look nicer than others. It’s also bad because developers will be able to produce hideous houses.
To avoid getting caught out by any changes, homeowners should make sure their plans get drawn up by an architect or registered building surveyor who is qualified to advise on planning and building regulations.
The government has made permanent changes to planning law, allowing homeowners in England and Wales to extend their homes without first having to go through a costly process of seeking permission from council planners. These new laws have been designed to cut out time-consuming bureaucracy, making it easier for homeowners who want an extension or loft conversion.
Planning experts say that these measures will benefit young families looking to buy their first house. It will also benefit those who do not have enough money saved to buy a home. If you’re considering adding space to your property for various reasons, take a look at this article on how those plans can affect your mortgage options before you make any decisions! It is better to be safe than sorry. As a member of the public, take this chance to expand your home for better living. If the conditions are favourable, why not?