Build a new home in your garden in Merton

For a garden in Merton to take a new house, three things have to line up: a safe way in, enough space to keep both homes private and light, and services that can reach the plot at sensible cost. Our free appraisal looks at all three before you spend anything.

If they line up, we move on to a measured survey, design and, where useful, pre-application advice from the London Borough of Merton. Planning permission is the council’s decision, so the design is shaped around the tests its officers apply rather than the largest house the plot could possibly hold.

Timber-frame house under construction with scaffolding at the bottom of a back garden, seen from the patio
Planning authority
London Borough of Merton
Postcodes
CR4, SM4, SW19, SW20
Noon sun, 21 March
About 39°
Shadow from a 5 m eaves line
About 6.3 m
Planning plan
Local Plan
County
Greater London

The local picture in Merton

Access is where a garden plot anywhere in CR4, SM4, SW19 and SW20 tends to succeed or fail. A new drive needs enough width for cars, clear visibility where it meets the road, and enough distance from neighbouring windows to keep noise and headlights in check.

Policies in the council’s Local Plan, along with any highways advice the council receives, decide the detail for your address. We measure the gap beside your house on the first visit, and if it’s too tight for a home that can be approved and built safely, we’ll tell you before any design fees are spent.

Section showing noon sun and shadows in Merton: about 39 degrees on 21 March and 15 degrees on 21 December21 m21 Mar, noon: sun 39°, shadow 6.3 m21 Dec, noon: sun 15°, shadow 18.5 mExistingNew home
This section is worked out for the latitude of Merton: around 39° of sun at midday in late March and about 15° at midwinter. It shows why the gap between your house and a new home behind it is about light as well as privacy. Garden assumed to face north.

What happens next in Merton

Once you ask for an appraisal of your Merton garden, we start with the paperwork: the title plan, any covenants, flood maps, tree and conservation designations, and planning decisions on nearby plots. A short call follows, then a site visit if the plot passes the desk check. You get our straight view of what’s realistic and what happens next, with no obligation to go further.

  1. Free plot appraisal

    We check the title plan, access, constraints and planning policy from our desk, talk the plot through with you, and visit if it looks viable. There’s no cost and no obligation.

  2. Survey and design

    A measured survey records levels, boundaries, trees and neighbouring windows. We then design a layout and house that suit the plot, the street and your budget, and decide whether pre-application advice is worth seeking.

  3. Planning and approvals

    We submit the planning application and manage it to a decision, then deal with conditions, Building Regulations approval, the structural warranty, any build-over agreement and the new utility connections.

  4. Written quote and build

    Once design and survey are complete you get a written quote. The build runs in stages — access and groundworks, foundations, frame and roof, fit-out and external works — with inspections at each key point.

Worth checking early

  • A build next door means months of noise, deliveries and contractors near your home; good planning reduces the disruption but doesn’t remove it.
  • Planning can be refused, and money spent on surveys, design and the application isn’t recovered if it is — which is why we start with an appraisal.
  • Your own garden gets smaller and the new home will be visible from your house, so screening and separation matter for both homes.

Merton: questions to ask

Can I build a house in my Merton garden and then sell it?

Yes. You keep the land while the home is built, then sell the finished house. Before building starts, the plot should be given its own title through a transfer of part at HM Land Registry, and if your house is mortgaged your lender must agree to release the plot. Selling a home you’ve built can change your tax position, so take advice from a tax adviser first.

Can the new home in my Merton garden connect to the main sewer?

Usually, yes, but the route and depth decide how easily. The new home needs its own foul connection, agreed with the water company, and gravity drainage is simplest where the sewer sits lower than the new floor. If it doesn’t, a pumped connection may be needed. Where a public sewer runs under your garden, a build-over agreement or diversion may also be required.

Do you visit gardens in Merton before giving advice?

We start with a desk review of the title plan, access, constraints and planning policy, then talk the plot through with you. If it looks viable, we arrange a site visit to see the access, levels, trees and neighbouring windows for ourselves. The appraisal is free and carries no obligation.

How close can a new house be to my own in Merton?

There’s no single national distance. Many councils use separation guides of around 21 metres between facing back windows and around 12 to 15 metres between a back window and a blank side wall, but the guidance used by the London Borough of Merton decides. Window positions, ground levels, roof shape and screening all affect what is acceptable, which is why we survey before we design.

Other options in Merton

Build in your garden near Merton

Find out what your garden could become

Free garden plot appraisal. No cost, no obligation, and a straight answer if it won’t work.