Double Storey Extensions

Double storey house extensions are one of the larger projects you can use to extend your home in Lincolnshire, and they are incredibly effective ways to add space to both the ground and first floor of your home. CK Architectural can help you build your own across the Lincoln, Boston, Louth and Grantham areas, as well as the rest of Lincolnshire too.

We work with you using your own creative vision as well as our own to design the perfect extension that works on both floors, utilising the space perfectly and ultimately creating an extension that you’ll love for years to come, designed for the future and to cater for your every need.

We’re able to offer a complete service taking your design from initial conception through to planning applications, building regulations, and even project managing the build to bring your project to life, all of which can be tailored to you.

Contact us today to speak to the team and get free advice and quotations on your project.

double storey extension Design, Planning and building regulations drawings in Lincolnshire


Before building your extension, there are some things that are important to consider in order to make the most of it. Things like the purpose of the rooms, access, light, ventilation and even means of escape all come into play. Each need due care and consideration. With two stories, the planning limitations have to be considered as the size and scale means it has to be designed to fit with the existing house. It’s wise to avoid creating inner rooms, as each habitable room will need an opening window. Clear glazing in double storey extension will generally not be permitted at first floor level within 7 meters of a boundary, so that is important to consider too.

The regulations are stricter than a single storey extension, specifically regarding fire escape and structure. You need to decide what you want to gain from the build, what you are willing to sacrifice, and the available budget for the entire project. Site checks should be carried out on shared boundaries, party walls, mains sewers, and to find if the property is a listed building or in a conservation area. Double rear extensions also have to consider the overshadowing and loss of amenity/outlook form the neighbours if in close proximity to the boundary lines.


The initial part of the design process works with your requirements to find out the best design options. Size and scale of the extension is the priority and considering how much you will need to build to gain the space and rooms you want. From there, the internal layout can be explored. Using the existing structure as best as possible to save costs is advisable, but it’s all dependent on your personal requirements.

A double side extension will need to look subservient to the house, and typically this is done by pulling the front wall back. Getting a good balance is important. If the need for a bedroom is driving the extension, you will have to make good use of the ground floor too. Once all of this is thought about, it’s then time for more specific design options, like external doors, lighting, roof styles, and even the room plan to account for placement of furniture, appliances, and fixtures and fittings.

Double storey extensions generally need planning permission, as the permitted development rights only permit smaller sizes. There are a lot of things to consider before submitting a planning application, so this needs attention of its own. How the build will impact the street scene, if it enhances character, any negative effects on the neighbour’s house or garden, and how it will affect light/privacy/amenity are all major points here. These are some of the things the planning officer will be checking whilst making their decision.

Our design consultants will give you the best advice on how to achieve your requirements with the best chance of securing planning approval. We will prepare and submit the application on your behalf, then act as your agent talking directly with the council throughout the application to provide as much support as possible in succeeding with the application.

double storey extension Design, Planning and building regulations drawings in Lincolnshire

You will need a building certificate from a building control body, either local authority in Lincolnshire or private building inspector, for your double storey extension to be built. That means providing detailed building regulation drawings. We advise gaining the planning permission before paying for the detailed building regulation drawings to prevent any unnecessary expenses. These building regulation drawings will then be submitted for a full plan check, amended if necessary and once approved they will be the standard that is built to and inspection against.

Our plans will include all the necessary detail such as structure, passage of sound, disabled access, heat loss, drainage, resistance to moisture, collision, impact, ventilation, light, emergency escape and much more. These drawings will be used when the building control officer inspects the build to ensure the builder is carrying out the works to specification. You can commence work 5 days from submitting to building control, which is the minimum time due to having to consult the water authority.


With the approved drawings you can now approach builders to provide quotation and price. Check that any quotation you consider will be written up clearly and with good detail. You will need to know exactly what is priced for and any additional costs should unforeseen issues arise. We have extensive construction knowledge along to assist you and builder throughout as well as a project management service to take care of all of this for you for a low fee, too. In any case, we will help you throughout the construction process and visit site if required.

Use our drawings in line with the quotation and make sure any additional information we don’t provide such as plumbing and electrics is agreed in detail before the first fix goes in. It will be costly changing thing once the initial preparation has been built. Remember when you finally do come to build your double storey extension in Lincolnshire, only half of the building works will be outside. You should plan and phase exclusion zones with your builder to make sure you have access to what you need.

If you need additional information about double storey extension, contact us today and we will provide you with all the necessary information.

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