Outbuilding Conversions

A popular solution for people requiring more space but reluctant to move is to convert an existing outbuilding into a new living space.
While most people associate outbuildings with stables and barns in rural locations, outbuildings actually include garages, outside toilets and coal sheds that can be found in many smaller urban properties. This means that you can build a guest room, garden room, home office, greenhouse or children’s playroom. While you can use your outbuilding for many purposes, if you intend to convert it into a habitable room it must be upgraded to meet the building regulations requirements for ‘a material change of use’. This means that you will have to insulate the building structure, and that doors and windows will have to be double-glazed. If you intend to install heating, plumbing or electrics all of these will also have to comply with building regulations.

Types of Conversion
The amount of time, money and effort that you will need to convert your outbuilding will depend on the type of building that you hope to convert and what you intend to use it for. The cheapest options can be a summer garden room or a greenhouse (which would not need heating, plumbing or electrics). In these cases the existing fabric of the building will need to be structurally secure and have proper ventilation.
If you plan on using the outbuilding all year round the building may also need to have a functioning heating and lighting system. If the outbuilding will be used as a guest annexe or as a home office, artist’s studio or children’s playroom you might also want to install electric sockets, internet access and running water, so that you can make a cup of tea and use computer equipment or other electrical goods.
You should make a careful assessment of what amenities you think you will need before you proceed. Calculate the costs of buying and installing all of the services you will require, including the cost of qualified tradesmen.


Some developments do not require full planning permission and are covered within Permitted Development. For further information or help on a project please contact us and we will be happy to advise you and discuss your project requirements in greater detail.

The more you insulate a building the easier and cheaper it is to heat, so investing in good insulation will save costs in the future. Insulation should be added to the interior of a single-skinned building between the original structure and the plasterboard interior. Although this can reduce the living space slightly, it will make the new room much more pleasant to spend time in, making it warmer in winter and cooler on hot summer days.
Damp-proofing will also make the room or building much more pleasant to spend time in, and will help to stop problems such as mould and rising damp developing inside the building. A damp course should be installed during the construction of the inner layer of the building. For timber structures a concrete base with a damp proof membrane can be used, or perhaps the wooden structure can be raised off the ground on blocks with a slate barrier in between the two materials.

What Type of Garage do you Have?
Garages tend to fall into three categories — attached, integral and detached. Each comes with its own issues:
Attached or Integrated: This type of garage is connected to the main structure of the house, sometimes to one side, but also often projecting out from the front of the house with a room above, commonly a bedroom. Attached garages can usually be accessed from inside the house, making the conversion even easier.
Detached: Just because a garage is detached does not mean it is not suitable for conversion into living space. However, you are more likely to have to apply for planning permission to change its intended use if it is a separate building.
How Big is Your Garage?
A standard-sized single garage can give you around 14m² of extra space, so is ideal if you are looking for somewhere to house a home office, playroom or guest bedroom — or even a downstairs shower room and utility. It might also offer the potential to extend an existing space, such as your kitchen or hallway, depending on the layout of your home.
A double garage can add around 28m² and gives you the option of using part of the space for storage or still as a garage and the rest as living space. The same goes for ‘tandem’ garages.
Can I Convert my Garage?
Check for any restrictive covenants or clauses that may prevent you from making changes that alter the external appearance of your home. Even if you find you are subject to such restrictions, you may still be able to convert the space, retaining the front section for storage and converting the rear area.
We also need to consider the following:
fire escape routes
structural soundness
• Foundations – often the foundations of a garage are not deep enough to handle the extra weight of floors, walls and ceilings so will need to be tested to see what strengthening is needed. Infilling door opening – should include suitable foundations, damp course, weather proofing and insulation.
• Structural strength – often garage walls are of single layer of bricks which may not be suitable to carry an additional floor, new roof or additional insulation.
• Weather proofing and insulation – the garage will need to be weather proofed and insulated if it is to be used as a living space.
• Windows and ventilation – windows will need to meet minimum energy efficiency standards and have adequate ventilation provided.


Some developments do not require full planning permission and are covered within Permitted Development. For further information or help on a project please contact us and we will be happy to advise you and discuss your project requirements in greater detail.


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