Step By Step
Garage Conversion Guide

A garage door is simply made to function as an entrance or exit of a car and is not suitable for the comings and goings of people. The fact that it is not aesthetically pleasing is only part of the problem. There’s also the matter of insulation and lighting. This means the door will have to be replaced with a wall, or “in-filled.” Often a door designed for people is framed into the new wall, and/or windows can be installed to let in more light, and ventilate the room. Be advised that the foundations of most garages are not practical for the load bearing of a new wall with structural integrity. Often that means that a new foundation will have to be laid. This is usually 8 inches of concrete poured at the base of the new wall. The process usually takes a morning to complete and then work can begin building the new wall. The new wall will be made of brick or black work ,depending on the exterior finish of your house and a damp proof course will be added to ensure no rising damp can penetrate.

The majority of garages have thin slabs of cement as floors. This floor might be can be removed or replaced. However, we often prefer not to tear up the old floor, but to build on top of it, such as adding what is called a suspended timber floor. This will be a raised construction that will allow for thermal insulation to be placed in the space between old floor and the suspended new floor. This is an efficient way to make sure the floor is properly insulated, takes care of moisture and is strong enough to bear the weight of the walls. The advantage of this approach is the new garage conversion will match the floor height of the rest of your house as well as providing an extra layer of insulation. Another alternative to removing the existing floor is to upgrade it with a variety of materials, rather than build a raised floor on top of it, as just described. Improving the existing floor can be done by layering on a damp-proof membrane, which is available in solid or liquid form. On top of this membrane is placed sufficient thermal insulation. Then it up to you for the choice of finish!

External walls come in two basic types: Solid walls and cavity walls. A solid wall is just that – one layer of bricks forming a wall. A cavity wall is a wall with a hollow centre inside of which thermal insulation is filled. Only a cavity wall will do for a room designed for human dwelling. The insulation is necessary both to make the home energy efficient, and is required by law. The wall must be moisture proof and constructed with fire resistant materials, not to mention being of sufficient strength the bear the weight of supporting the roof and overall structure of the home. Most existing garage walls are single layer walls, meaning they are not thermally sound and will not meet building codes. So every exterior wall will be insulated to reduce your energy bills, comply with building regulations and make sure your new garage conversion is warm enough that you’ll want to use it.

The roofs of most garages are already water proof, but the vast majority of them will need to be upgraded to serve as a roof for a comfortable room. The process of upgrading generally involves adding additional insulation to the roof, again to ensure the house doesn’t loose heat and to satisfy building regulations. Then you have the option of a flat roof with storage space above or a pitched ceiling. Some garage roofs are flat. This type design must have sufficient insulation applied to comply with building regulations. As in most insulation schemes, a thin ventilation gap between layers helps create a thermal barrier keeping the cold out in the winter and the cool air inside in the summer. This layer of separation is usually 50 mm. Pitched garage roofs generally have extra insulation placed between ceiling and roof.

It is popular for many conversions to have a ‘knock through’ or a door fitted between the house and the new conversion. Some prefer an archway rather than a door, either way, a concrete or steel lintel is used to contain the structure of the wall and a door or arch is then fitted. In some cases a larger arch or gap is requested to provide an open plan space, this will require an engineers report to ensure your safety and the buildings structure is sound.

PLUMBING Most of our customers request at least one radiator and all of the work is performed by a registered plumber. It is advisable that all plumbing work should be carried out by a qualified plumber or when gas is involved, a registered Gas Safe engineer. Many of our customers request that old boilers are removed form the garage and we’re quite happy to help. ELECTRICAL As you would expect with any conversion the options of lighting & sockets are unending but as soon as you have chosen what you want we will get everything installed by our electricians. All electrical work and wiring must meet the standards as set down by British Safety Standards 7671. In all cases a SELECT certificate is required to achieve your completion certificate. If any new electrical work is undertaken, and your current electrical system is found to be out of date, then this must be updated at the same time as the conversion to comply with building regulations. This is the realm of professionals and certified electricians and therefore it is worth leaving this one to the experts. VENTILIATION All rooms require proper ventilation – but not all rooms require the same amount of ventilation. So much depends on what kind of room you plan to use your converted garage space as. A ventilation window or windows must equal at least one-twentieth of the rooms total floor area. All new windows located in confined spaces require fire hinges fitted to the windows. Ventilation is also achieved with certain devices, such as extractor fans or trickle vents. Kitchens and toilet/shower areas are required to have extractor fans if window ventilation is not adequate. Fan ventilation capacity is measured in terms of litres per second.