House extensions in North London and Hertfordshire
Single-storey, side-return and two-storey extensions, including the steelwork, glazing and finishes. One team manages the whole build, from the first site visit to handover.
What’s included
We handle the whole job, so you have one team responsible from the first site visit to handover.
- Groundworks, foundations and piling where needed
- Steel beams and structural openings into the existing house
- Large glazing, sliding doors and roof lights
- Kitchens, bathrooms, flooring and decoration
- Heating, electrics and plumbing for the new space
- Coordination with your architect, engineer, party wall surveyor and building control
Common questions
General guidance only. Your architect or the council can confirm what applies to your house.
Do I need planning permission for an extension?
Not always. Many single-storey rear extensions can be built under permitted development, which has limits on depth, height and materials. Houses in conservation areas, listed buildings and flats have tighter rules. Your architect or the council can confirm what applies to your house before you commit.
Do I need building regulations approval?
Yes. Every extension needs building regulations sign-off, whether or not it needs planning permission. We work with building control throughout the build and hand over the completion certificate at the end.
Will I need a party wall agreement?
If the work involves a shared wall or digging foundations close to a neighbour’s, the Party Wall Act usually applies and notices have to be served before work starts. We can put you in touch with a party wall surveyor we work with.
Can we stay in the house during the build?
Often yes, especially for rear extensions where the existing house is closed off until the last stage. It depends on the size of the job and how much of the house is affected, and we talk it through at the site visit.
Planning a project?
Tell us what you have in mind and we will come back to you within one or two working days.