They are the most common way to add living space because they avoid disturbing the upstairs rooms, can often go ahead without a full planning application, and let you rethink how the ground floor flows.
Rear extensions
A rear extension pushes the back of the house into the garden. It is the usual choice for a bigger kitchen, dining or family room, and often the simplest to build because it only meets the house along one wall.
The trade off is garden space and daylight to the rooms behind it. Rooflights and wide openings compensate for that.
Side and wrap around extensions
A side extension uses land beside the house, often a narrow passage or driveway. On terraced and semi-detached houses a side return extension turns wasted alley into usable floor area. A wrap around combines side and rear, creating an L shape that gives the most space of all.
Wrap arounds are more complex. There are more junctions with the existing house, more roof and more structure, so they take longer to design and build.
Front extensions and porches
Extending forward of the house changes how it looks from the street, so planning is stricter. Small porches can fall under permitted development, but most front extensions need a planning application and a design that suits the house.
Planning permission and permitted development
Permitted development allows many single storey rear extensions without a planning application, within limits on depth, height, eaves and materials. Side extensions have their own width limits. Conservation areas, listed buildings and houses that have already been extended lose some or all of those rights.
Where permitted development does not apply, a householder planning application is needed. In both cases the work must meet building regulations for structure, insulation, drainage, fire safety and ventilation.
- Check whether permitted development rights still apply
- Consider a Lawful Development Certificate for certainty
- Allow time for a householder application if needed
- Building regulations apply in every case
Design decisions that matter most
Roof type is a big one: a flat roof with a lantern, a pitched roof with vaulted ceiling, or a lean to. Each affects light, internal height and how the extension looks against the house. Materials matter too, whether matching brick or a contrasting finish such as timber cladding.
Inside, decide how much of the original back wall comes out. A fully open plan room needs a longer beam and careful heating design, while keeping some wall can create more defined spaces.
Build order in brief
Foundations are dug and inspected, walls and roof go up, then windows and doors make the shell weathertight. Only then is the existing house opened up, followed by first fix, plastering, screed and finishes.
Questions to settle before drawings start
Before paying for drawings, be clear on what the new space is for, how much garden you are willing to lose, and whether you want one open room or separate spaces. Find out whether the house has been extended before, because that can use up permitted development allowance. Look for drains, manholes and trees near where you want to build, since each can change the foundation design.
Having those answers ready makes the first site visit far more productive and gives the designer a clear brief to work from.
How we approach a ground floor extension
We start with a free site visit to look at the house, the plot and what you want to achieve. Our design and planning service can prepare drawings and applications, and our own team carries out the building, carpentry and roofing. You receive a fixed-price written quote before work starts.
With over 40 years of experience, we have built extensions on everything from modern homes to old cottages.
Common questions
Which type of ground floor extension adds the most space?
A wrap around extension usually adds the most floor area because it uses both the side and rear of the house.
Can I extend without planning permission?
Often, under permitted development, if the extension stays within the size limits and your house still has those rights. A Lawful Development Certificate confirms it.
How long does a ground floor extension take to build?
It depends on size and complexity. We give a programme alongside the fixed-price written quote after the site visit.
Do you handle the drawings?
Yes, through our design and planning service, or we can work from drawings you already have.