Guide to Building an Extension
Building an extension is one of the most popular ways of improving your living space, whilst avoiding the hassle and expense of moving. Having an extension may well also add value to your existing property.
Building an extension is a big commitment and there is a lot of information you need to know before embarking on your project.
What Permissions/Consents do I require before Building an Extension?
Depending on the size and position of your extension, you might not require planning permission. This will depend on whether your proposed extension complies with Permitted Development (PD).
The easiest way of determining whether your proposed extension falls under permitted development is by referring to the interactive house on the planning portal website.
Permitted development rights can be restricted in designated areas, such as: Areas of Outstanding Natural Beauty, Conservation Areas, etc. There are also situations where they do not apply, for example: if your property is a Listed Buildings or if the original house’s planning consent had a condition which restricts permitted development.
RA Architects can help you to understand whether your proposed extension complies with permitted development guidelines, and if not, how likely your project is to gain planning consent. Call now to book a site visit with one of our team members.
What is a Lawful Development Certificate? And Do I Need One?
A Lawful Development Certificate (LDC) merely provide confirmation (from the Local Authority Planning Department) that a proposed extension meets PD requirements. So, getting a Lawfulness Certificate is not necessary if you are confident the proposed extension meets these criteria. However, you might want to get a Lawfulness Certificate anyway, to keep with the deeds of the house, so that any future purchaser knows that the extension is lawful. A Lawful Development Certification application costs £103 in England or £95 in Wales.
All alterations to listed buildings, including internal ones, require consent and it is a criminal offence to alter a listed building without it. If these alterations would usually not require planning permission, then consent can be sought through a Listed Building Consent application.
The planners will always regard the existing listed property as more important than what you are proposing to add to it. Any extension will therefore have to respect the character, appearance and historic material used in the construction of the original house.
Whether you require planning consent or not, if you are proposing a heated extension to your home, you will need to make sure you comply with Building Regulations. There are two methods of getting Building Control Approval:
Full Plan Submission: send detailed plans to your local authority building control or approved inspector prior to get approval for the proposed scheme. The building inspector would then visit the site at several stages to check that the works are being completed in line with the approved drawings.
Building Notice: With this method, you submit an application to the local authority building control or approved inspector, notifying them of the work shortly before it starts (check individual company for the required notice). Building inspectors will then inspect the work at various stages to ensure it complies with Building Control requirements.
A Building Notice is the riskier option as you may only find out you have a compliance issue once building work has started. This may be costly to correct.
Having a set of detailed drawings from an Architect can help avoid this issue. RA Architects can provide comprehensive detail drawings and notes, to help your contractor to price accurately and ensure the proposed works comply with the Building Regulations.
Party Wall Consent
If building your extension involves either:
You must inform the Adjoining Owner or owners by serving a notice. A Party Wall Surveyor can advise you further on this process and what to do if your neighbour does not accept the notice.
For further information, refer to:
Build Over Sewer Consent
Should you find yourself with a sewerage system within 3 metres of your property, it is mandatory for you to apply for a build over sewer agreement with your water supplier. This is carried out with an assessment and trace of the sewer line which will also determine ownership. This is difficult to receive so keep this in mind when planning your build. For further information regarding these, please follow the link –
What other things should I Consider Before Building an Extension?
How easy will it be for equipment and materials to be delivered to your home when building an extension? You’ll need to consider how deliveries of large items will be undertaken. You’ll also need to determine where a builder and their sub-contractors will park and store their tools.
Demands upon Your Services
We recommend giving your current services a review. It is important to confirm whether your current services will be able to sustain the added room. For example, while replacing the boiler is an option, you could also look at alternatives such as electric underfloor heating, this is a beneficial way of heating a room without over working the facilities.
It is important to notify your home insurer of the proposed work. Some may not provide cover during the works and others will offer dedicated extension insurance products.
If you are designing your new home, an open floor plan with a seamless transition from the indoor space to an outdoor veranda is a great feature to include. Open layouts are becoming more and more popular in modern homes as they give the illusion of a bigger space, provide more natural sunlight and outdoor views, and create a more safe and social environment.
To create the feel of one large and connected space, abolish any distractions or eye sores and use floor to ceiling glass where possible. Finish off using similar flooring and wall papering/ paint to complete a flush, modern look that gives the illusion that the space is one. A veranda offers many benefits, these include adding value to a home and providing additional space.
Not only will your room have the illusion of being bigger, you will feel closer to nature. Using large floor to ceiling windows with minimal lines will bring in natural sunlight and allows you to enjoy the landscapes of your home.
Small spaces, Big ideas!!
With the benefits of living in the City Centre growing rapidly, more and more people are searching for their perfect home. The only downside is according to a report released by the Commission for Architecture and the Built Environment, we are living in “rabbit hutch Britain”, with new homes ranking as the smallest in Europe.
So with this in mind, adaptability is key when it comes to fitting your lifestyle into a small home. Incorporating hidden storage and plenty of light can make any home feel bigger and brighter.
Did you know that buildings don’t have to be old to be listed? Listing was started in 1947 as part of the Town and County Planning Act to guard specific properties for post-war builders. To be listed, a building needs to be of particular architectural or historic interest.
Completed in 1987, the Inmos Microprocessor Factory in Newport is of particular architectural interest and was listed in 2007. The reason why this factory is listed is that it has a unique design structure. The architect, John Young, designed all of the exteriors of the building as the support systems, which meant that no columns are holding it up inside. This building was also designed as a sort of kit so that it could be constructed quickly in many different places. This design additionally ensures that there would be no disturbances to the running of the factory if any extensions were to be added.
Architect: Richard Andrews Architects
Works Undertaken: Feasibility and planning, detailed design and tender plus contract and project overseeing.
Client: Private Domestic Client
Cost of Work: Undisclosed
Contractor: So Exclusive Developments
We were approached by our client and their family to help design a new build studio apartment within the grounds of their existing family home. As our client has a disability that affects mobility and is dependent upon using a wheelchair it was essential that we designed a fully level home, that allowed circulation paths for the wheelchair throughout all the rooms. We encorporated wide external and internal doorways and included a ramp leading from the rear decked terrace to a garden area below.
The large bedroom and ensuite was designed to give ample space for hoist access to the bed and bath with the addition of a wetroom style shower, lowered WC and stylish vanity units.
Another consideration we needed to address was that our client also required a team of carers present at all times. We wanted to design a home that not only allowed our client their privacy and living space but also gave sufficient space for visiting guests and carers. We proposed an upstairs wing, with private bedrooms, a small sitting/study area and a bathroom with shower enclosure.
Making someone's quality of life better truely is the passion behind our practice. If you have a project you'd like our help with call our team on 01633 744144 or email firstname.lastname@example.org
Architect: Richard Andrews Architects, project overseen by Associate Lewis Shaw
Works Undertaken: Feasibility and planning, detailed design and tender plus contract and project overseeing.
Client: Private Domestic Client
Cost of Work: £100,000+
Contactors: TLC Building Services
To create a contemporary single story rear extension, with enough room to accommodate a kitchen, dining space and family area. Also to add a side extension to make room for an office and library space.
Unique Design Features – Once finished the exterior to the property showcases a beautiful white render contrasted against timber cladding. A wrap around window on the corner of the office side extension enhance natural light. Crittall style doors frame the view from kitchen to garden and allow a smooth transition from inside to out and the addition of skylights and high placed windows spanning the width of the extension bring a bright and airy family space.
Our clients contracted TLC Building Services to complete the work with ourselves overseeing the contract administration and project management.
There is still a tiny bit more work to do before the propery is complete (namely applying the crisp white exterior.) However already we can see what an improvement the new living space has made for our clients. If you're thinking of embarking on a similar project, we'd love to get involved. Contact the team on 01633 744144 or email email@example.com.
Architect: Richard Andrews Architects, project overseen by Associate Lewis Shaw.
Works undertaken – Feasibility and planning, detailed design and tender plus contract and project overseeing.
Client: Practice Owners of Cwmbran Village Surgery, partly funded by Aneurin Bevan Health Board
Cost of Work: £450,000+
Contractors: White Brothers & Speed
The practice owners contacted us to help resolve several design challenges for their surgery, which opened 25 years prior and was long overdue an update. We quickly established that the surgery's main challenge was that the building was too small for the amount of patients registered – with a poor internal layout and a lack of consulting and treatment rooms. We proposed a single front extension to expand the reception and administration spaces, with a second two storey extension housing consulting rooms to the side. The heart of the design stemmed from creating a centralised waiting room with the treatment and consulting rooms arranged in wings to improve the patient flow around the building. An installation of a lift to the upstairs floor rendered the practice compliable with the Disability Acts Standards, whilst we improved patient experience through light, modern and airy rooms.
The 3D Render Design
The dual extension accomodates 4 new consultation rooms and two new treatment rooms, an enlarged waiting/ reception area plus a reconfiguration of the adminstration and staff spaces. This particular project required the use of all three of our stages of work. The first of which was feasibility, planning and design. We gave a number of design options for the practice and worked together to choose the most practical. We then prepared the final design to be put through Torfaen County Council planning department. We submitted the planning application on behalf of our clients (including all forms and administration) and liaised with the Torfaen council to achieve a positve result.
The next stage was to provide a detailed design. Using our extensive knowledge of constuction and regulations, we created detailed drawings for the builders to work from. Following which we consulted with engineers, building control and other professionals as necessary to ensure the project fully buildable and compliant. We then administered a tender package to a number of building contractors to assure the best price and quality for the build works.
Our clients choose White Brothers and Speed to complete the works, which took place from early summer 2017 to completion in April 2018. We administered a contract between White Brothers and Speed and Cwmbran Village Surgery, based on our detailed drawings, our understanding of construction laws and contact negotiation. We then throuh regular site visits checked the building work to ensure the work was being delivered in line with our drawings, regulations and was to the standard allowed for in the tender.
Testimonial from Practice Manager Sian Whitcombe
To Lewis and the team at RA Architects. A big thank you for all your hard work and dedication to this project. Your professionalism has been exemplary and we would not hesitate to recommend you to others.
We will be publishing a video documenting a behind the scenes look of the works undertaken to the surgery within the next couple of weeks. Make sure you follow us on social media to keep up to date!
Our clients approached us looking to create a sympathetic double storey extension to their cottage home. Having already being in possession of a design they were happy with, we were instructed to oversee the project works. We implemented the RIBA domestic works contract between our clients and their chosen contractor, Fern Bay Properties, ensuring over five seperate site visits that all work was being completed safely and adhered to both building regulations and the client's original plans.
We regularly undertake a range of commissions varying in scale and complexity. We can take on 'Full Service Appointments' which run from conception to completion and we are also happy to assist clients in any isolated project stages. If you would like to talk to us regarding your own scheme, please contact the team today to book a free consultation.