Garage conversions are perhaps the least evasive way of adding additional living space to your home. It is also the most affordable way of creating additional space within the home. With many people no longer using garages to house their cars the humble garage has turned into a storage area often containing things you no longer need.

By adapting the construction of the garage with the addition of some insulation, a floor upgrade and perhaps a window to replace the garage door you can turn this old storage area into a stylish dining room, or perhaps a home office.


Typical Home Improvement Guide Garage Conversions
A garage conversion is one of the most straightforward ways to create an additional room in your home. During our initial site survey we will go through your plans for your garage conversion and advise if this can be achieved. We will also offer advice and assistance should you require any design input from us based on our experiences.


Will I need planning permission for my garage conversion? 
Under regulations that came into effect from 1 October 2008 the permitted development regime covering garage conversions changed and planning permission is not usually required, providing the work is internal and does not involve enlarging the building or external alterations.


Sometimes permitted development rights have been removed from some properties with regard to garage conversions and therefore you should contact your local planning authority before proceeding, particularly if you live on a new housing development or in a conservation area.


Furthermore, if you live in an area where parking is problematic then it is also possible that permitted development rights may have been removed for such conversions.


Although planning permission is not required for garage conversions, if you are obtaining a set of building regulation drawings from us for your proposed conversion we will always advise you to apply for a lawful development certificate from your local authority as without written documentation that your conversion did not require planning permission you will be asked to pay for an indemnity insurance to cover the garage conversion when the time comes to sell – these are generally considerably more expensive than the councils fee for a LDC.


Will I need building regulations approval for a garage conversion?
Please note, even if planning permission is not required for your garage conversion you will still require building control approval. The key points requiring building control approval are as follows:-


1) In-fill Garage Door

As part of the garage conversion, it is likely that the original garage door will be infilled with a new wall and possibly a window or door. As the foundation to the existing garage is not likely to be traditional (it’s probably a shallow slab), a new foundation may be needed for the new wall. The existing foundation may be checked by digging alongside it until it’s bottom is reached.

Foundations are required to transmit the load of the building safely to the ground. Therefore, all buildings should have adequate foundations (normally concrete), which will vary from one project to another depending on the circumstances of each case.

These foundations can be cast as deep-fill (filling most of the trench) or shallow-fill (where the minimum thickness to transfer the load to the soil is provided).


2) Flooring
The existing garage floor is likely to be strong enough for general domestic use, but may need to be upgraded to ensure it is adequate in terms of damp-proofing and thermal insulation. It may also be desirable to change the level of the floor to match the levels in the existing home.

The simplest way to achieve this would be to ugrade the existing concrete floor. Alternatively, if levels permit, an new timber floor could be constructed over the existing concrete floor.


Solid Floor
The existing concrete floor can be used as a base, however a new damp proof membrane (DPM) will need to be introduced. DPMs come in solid or liquid form, the latter being a practicable solution for a garage conversion. Manufacturers will be able to advise. A suitable gauge damp proof membrane (DPM) and thermal insulation must be provided. These can be laid over the sand blinding or on top of the concrete.

Thermal insulation may be required and can be placed on top of the membrane (if a liquid membrane is used care should be taken to ensure the two materials do not react with each other – a separation layer may be needed). The exact details will vary depending on which products are used.

The floor can be finished with a layer of screed or a timber covering (“floating floor”) the exact specification of which will depend on the insulation material used beneath. A screed is likely to need to be in the order of 75mm thick and should include a reinforcement mesh to prevent it cracking.

Care should be taken to ensure any existing airbricks for the main house are not obstructed by this work. If so, they should be extended through the new floor to external air.


Suspended Timber Floor
The existing floor level to the house may be quite high above ground, and in cases such as this it is more practicable to use timber joists, with a void underneath or build up with concrete. A minimum gap of 150mm should be kept between the existing concrete ground and the underside of the timber. The timber floor joists must be sized correctly depending on their length. They are then laid across the shortest span from wall to wall with a gap underneath.

An intermediate wall with a small footing may be needed to reduce the span and keep the thickness of the floor joists to a minimum. A damp proof course (DPC) should be placed on the underside of timber. Insulation is then placed between the joists (thickness required depends on the product used). Air vents should be placed underneath to provide ventilation to the void and the air should be able to travel from one side of the building to the other.

Prices banded around by companies varies so much that it can seem almost impossible to decide which price offers greatest value for money.


At DC Architectural Designs, my prices are fixed at the lower end of the scale because my overheads are low and I believe that if I offer a great service at a great price I will never be short on customers or recommendations from friends and relatives.


Why call or email – to request a detailed quote for your project? I never sell on your details and your personal information is removed from my system after a period of 6 months. Furthermore no sales people will call to follow up on the quote, I will simply leave you to decide whether or not you wish to join the ever growing list of very satisfied clients.