External wall insulation in Barnet

Barnet's houses, from Chipping Barnet to Edgware

Barnet is one of London's largest boroughs, and the housing changes a lot from one end to the other. Chipping Barnet and New Barnet keep a good share of Victorian and Edwardian terraces, mostly solid brick. Down through Whetstone, Mill Hill and Edgware the interwar semi takes over, with bay fronts, hipped roofs and, very often, a render or tile-hung panel on the first floor.

Most of those interwar houses were built just before cavity walls became the norm, so a large number are solid-walled even though they look modern next to a Victorian terrace. Chipping Barnet also sits on some of the highest ground in London and takes more wind and rain than the inner boroughs, which is exactly where a warm, weatherproof outer wall makes a difference.

What changes on a Barnet semi

On a typical Barnet semi the insulation goes on the side, rear and usually the front, wrapping round the bays. Many of these houses gained a side extension or garage later, often in a different brick, and the system is the chance to pull the whole house together under one finish.

Tile-hung first-floor panels are either removed and insulated behind, or detailed around if you want to keep them. Sills are extended, downpipes are brought out on new brackets, and the render is returned into the window reveals so the frames do not become a cold edge.

• Warmer rooms that reach temperature faster and hold it longer
• Less heat loss through solid walls (Energy Saving Trust)
• Fewer cold spots where condensation and mould form
• A fresh render finish in a colour and texture you choose

We don't quote specific savings figures. Your surveyor explains what results are realistic for your property.

A recent Barnet job, from bare brick to finished

This 1930s semi in Barnet is the kind of house the borough is full of: solid brick, a two-storey bay with a tile-hung panel, and a porch on the front. The job was to insulate the outside walls and give the house one clean render finish.

Once the scaffold was up, insulation boards were fixed to the brick, meshed and base-coated, then finished in render, with the bay and porch detailed by hand so the new wall thickness sits neatly round the windows.

How a Barnet job runs

A surveyor visits, checks the wall build-up, damp risks and the planning position for your road, and looks at the party wall line with next door, where the insulation stops neatly at the boundary. Most Barnet semis have a front drive, so the scaffold can often stand on your own ground. Where it has to go on the pavement it needs a licence from Barnet Council, which we arrange.

You get an itemised written quote covering the system, render, detailing and scaffolding. On site the boards, mesh and render go on in sequence with a daily clean-down, and the job ends with inspection, sign-off and warranty paperwork.

Barnet's semis, terraces and the Suburb

The 1930s semis that line the Northern line corridor through Woodside Park, Whetstone and Totteridge are classic EWI candidates: solid nine-inch brick, timber-framed bays and a rendered or tile-hung first floor that is often ready for renewal. The detailing around those bays, and around the side returns many of these houses gained later, is where a job is won or lost.

One honest caveat: Hampstead Garden Suburb falls inside the borough, and external changes there are tightly controlled by the Hampstead Garden Suburb Trust. Street-facing EWI is rarely realistic in the Suburb, and we say so at survey rather than after a refused application. The Victorian terraces of New Barnet and Chipping Barnet carry no such restriction on most streets.

Barnet EWI questions