Building over your garage can be a very cost-effective way to add space and value to your property. A by-product is that the extension should actually improve the look of the house and balance the elevation. However, there are several considerations you need to make before taking steps towards making your extension a reality.
Many young families see this as an ideal opportunity to provide the extra bedroom that their family desires, or to provide a home office to allow a dedicated space for home working. This is particularly prevalent given the recent Covid-19 lockdown.
Does Your Extension Comply?
Under permitted development guidelines there is no allowance for an extension over a garage. As such, you will require planning permission. However, each Local Authority will have a ‘House Extension Design Guide’ which outlines the criteria under which this would be considered acceptable. This includes:
It must not extend right up to the boundary as this can cause a ‘terracing effect’
It should be set back from the front of the house
The ridge should be lower than the existing, as should the eaves
The extension should not ‘overlook’ or be ‘overbearing’ to a neighbour’s property
This must largely replicate the details of the existing house
A flat roof is considered detrimental to the street scene
Buildings in a conservation area, greenbelt, or open countryside will attract additional scrutiny from the Planning Officer and may require input from the Conservation Officer too. In these scenarios the impact of the extension on the character of the wider area will be assessed.
Providing that your extension meets all the above conditions, you can start to look at the practicalities of getting your extension built.
Building Regulations
The other hurdle to contend with when considering your extension is building regulations. You must ensure that your project meets all of the necessary considerations with regard to foundations; energy efficiency; wall and floor separation.
All aspects require approval from the BCB (Building Control Bodies) and the relevant Local Authority.
Foundations
Building on top of an existing structure inevitably increases the load on the lower structure, i.e. the garage. This is a fundamental consideration because garages are generally only designed to house a car and may therefore only be constructed with a single layer of bricks. Solid foundations are required to safely bear the load of the whole building.
Furthermore, the capacity of the ground and sub-terrain of the property must now be able to bear the weight of a two-storey load. As the weight (load) from the foundation is transferred to the ground it spreads downwards and outside the footprint of the property at an angle of 45 degrees. If there are any drains or sewers in the immediate vicinity, there is a risk of cracking or other damage.
Energy Efficiency
Depending upon the proposed use of the extension, radiators, external wall insulation and loft insulation may all be necessary to maximise energy efficiency. You might want to consider installing solar panels into the newly constructed roof to optimise eco-friendly credentials. No matter the purpose of the extension, all elements used in the project need to conform to current Building Regulations.
Walls and Flooring
The walls and flooring of your extension will need to bear the weight of supporting beams. Furthermore, the contents of the space must conform to fire regulations. The installation of wall, flooring and ceiling fireproofing protection will be considered in the context of how the rest of the property is used.
Other factors such as smoke alarms, egress windows and fire-safety doors fall under fire regulations on new building projects. Building over a garage will require fire protection to the garage ceiling. This is because the risk of fuel spillages, combustibles in storage causing fires are increased in a garage compared to a living area.
Help is at Hand!
It is exciting to think of building an extension to your property. However, it is a task that must be handled with the utmost care and professionalism. Involving EDG Architecture at the earliest opportunity will ensure all aspects are thoroughly considered, and that you are able to progress in a timely manner. We’ll also ensure your new space incorporates the most advanced design features.
Contact us now to see how we can help. We offer a free consultation where we discuss your requirements, any planning issues, and any restrictions for the build itself.
