We work with clients to realise their dream home by providing modern architectural design for extensions and conversions as part of the planning and building warrant application process. We provide a fully integrated service covering architectural and structural design in one package. We can provide 3D visualisations, from simple sketches to fully rendered images and walk throughs of your proposed modifications to assist your understanding of the work to be carried out.Get in touch
Our services cover the design development, planning and building warrant application submission stages of all residential development from the conversion of garages and lofts to extending your existing home. We endeavor to make the design process enjoyable and exciting as well as focussed and well informed.
For the majority of development, planning consent will be required. We can advise on the need for planning consent, and where required we can prepare and submit all documentation required for planning permission to be granted acting as your Agent throughout the process.
A building warrant is required for most alterations e.g. extensions and loft conversions. Minor works including the installation of French doors also need a building warrant. We can advise on the need for a warrant and prepare and submit all documents and act as your Agent until the warrant is granted.
If your having trouble imagining what your extension or conversion will look like then we can prepare a 3D model of the extension or conversion providing high quality images, videos and even a walk through model
Unlike many other firms we undertake all structural calculations associated with your extension or conversion. You don't need to employ a structural engineer separately as we will take care of everything.
We have template contract documents you can use when employing a builder to undertake the construction of your extension or conversion. Having a contract provides additional protection should something go wrong.
We do not undertake any building works ourselves. However we can provide you with a list of builders used by several other clients. We cannot take responsibility for the performance of any builders.
The cost for constructing an
extension/ conversion depends on a number of factors including the type
foundations, the insulation properties of the existing house and the
standard of finish amongst many others. Use the calculator below to
estimate the approximate cost of your
The fee is based on the estimated cost of the building works. This may be based either on builders' quotations or on cost figures published by recognised bodies such as RICS. Use the calculator below to determine the fee based on the value of building works.
The fee payable to the local planning authority for typical householder/domestic work is £300.00.
Following an initial meeting to discuss the works to be carried out we will provide a fixed fee quotation to prepare the necessary drawings, specifications and calculations and act as you agent during the application process until consent is granted. Unlike other companies, we will provide project specific construction details and all structural engineering inputs necessary for each application within our fixed fee. Prices for preparation of all drawings and documentation for planning permission and building warrant start from:
Garage conversions - £800
Sun rooms - £1,300
Loft conversions - £1,800
Single storey extensions - £1,300
Two storey extensions - £1,900
Where your extension contains a large proportion of glass there may be additional costs associated with further structural engineer input and/ or the need to carry out additional energy/ thermal calculations
"Alan provided an exceptional service from start to finish. Very knowledgeable about our councils requirements re planning etc. Nothing was too much hassle and lways quick to respond to any queries. Couldn't have asked for a better person to help us design what feels like a brand new home."
"Alan was extremely professional and always available to answer any questions o address any concerns. He has an excellent knowledge and this means he is able to provide very good advice. We love our sunroom and it turned out exacly the way we wanted"
"You did a great job and my sister and her family send their thanks also. I also must note that your work/drawings are very detailed and probably the best I've seen amongst other designers I have used in the past for my projects."
"Excellent Service! Alan is really knowledgeable and helpful. He was very professional and I loved that he was able to show us an idea of the finished rooms on the VR headset. Would highly recommend to anyone thinking of extending and wouldn't go anywhere else."
"I hired XL Design to come in half way through a house extension that had lots of problems due to a bad builder, the previous architect was very slow and not up to the job either so it was pretty bad position to be in. They responded to my advert on mybuilder, I explained the problem in a message and gave him the address to the site. He was very quick to respond to my message and quick to make arrangements to come see the extension. He surveyed the extension, made recommendations, drafted a new building warrant with the needed changes and submitted it and got us approval on the extension. He is fast and professional and certainly put my mind at ease about the whole project. His fee is fair and I feel he offers a very good service. I would gladly recommend and use XL Design in the future. Wish I started with them in the first place."
"Gave me some invaluable advice at, probably, an inconvenient time to himself. Hugely knowledgeable and extremely reassuring. Can't thank you enough."
"XL Design was recommended by a friend. Their service is excellent value. They give lots of attention and always available to answer queries. I wouldn't hesitate recommending them."
"We have used the services of XL Design and have been very impressed. Professional, helpful, considerate and just really good at delivering great designs. I would recommend them to anyone that is thinking about extending. Creative ideas and a very competitive price"
"Excellent professional service from start to finish. We were kept informed of progress throughout the process. All dealings with planning and building were handled by XL Design. Overall a really quick and effective way to get started on home improvements. I would (and have twice now) recommend XL Design."