GS Renovation builds extensions across East Barnet, on the Victorian terraces near the village and the interwar semis around them. Ground conditions in EN4 change with the fall towards the Pymmes Brook, so the foundation design and the drainage strategy are settled before anything is dug, not discovered halfway through. We handle groundworks, steel, roof and fit out as one job.
Foundations and flood risk near the Pymmes Brook
Parts of East Barnet sit in a flood risk zone, and the low ground either side of the Pymmes Brook through Oak Hill Park and past Brookside is where that bites. It affects three things on an extension: whether a flood risk assessment has to go in with the planning application, where the surface water from the new roof is allowed to go, and how deep the foundations need to be in ground that may be alluvium and made ground rather than the clay you find higher up. We check the flood map for the actual address before drawing anything.
Where the brook is a designated main river, work close to the bank can need consent from the Environment Agency as well as planning permission from Barnet Council, and Barnet is also the lead local flood authority for surface water. None of that stops an extension going ahead. It does mean the drainage strategy has to be real: soakaways sized for the ground that is actually there, or a controlled discharge, rather than a note on a drawing saying the water goes to a soakaway. On heavier clay a soakaway often will not work at all.
Rear and side extensions in EN4
On a Victorian terrace near the village, the usual scheme is a side return infill alongside the rear addition, or a full width rear extension replacing it. The wider interwar plots further out take a deeper single storey rear or a double storey addition with a bedroom over a bigger kitchen. In both cases the existing drainage is the thing that shapes the plan. Old terraces here often have a shared drain and an inspection chamber sitting exactly where you wanted the new kitchen, and building over a public sewer needs an agreement with Thames Water.
Some of this is permitted development and some is not, and it depends on the individual house rather than the street. Whether the property has been extended before, how close it goes to the boundary, whether it is a terrace or a semi, and whether an Article 4 direction or a conservation area applies all change the answer, so we check with Barnet Council before design is fixed. Building regulations approval is separate and always needed. Where the foundation is dug within three metres of next door's wall, the Party Wall etc. Act 1996 applies too.
- First fix and second fix plumbing and electrics throughout
- Steel goalpost frames where the rear wall opens up
- Bi-fold, sliding and French door openings to the garden
- Side-return and rear extensions
- Wrap-around extensions and infills
Why East Barnet Homeowners Choose GS Renovation
East Barnet homeowners choose GS Renovation because we do the unglamorous work first. Flood map, trial holes, existing drain runs and the foundation depth the ground actually needs, all settled before the first cut of the spade. Then groundworks, steel, roof, services and fit out under one team, with Barnet Council building control inspecting as we go and the certificate handed over at the end.
- Clean, tidy and reliable tradespeople
- A written scope and programme agreed before work starts
- Foundation depth set after trial holes, drains and trees are checked
- Scaffolding and site set-up planned for tight London plots
- One point of contact on the phone, not a call centre
- Photographs kept at each stage for your records