Extensions & Projects · Essex & East London
Building a new house - whether on a garden plot, a self-build site, or replacing an existing dwelling - is the one project type where the rules are simple: there's no permitted development route, and every scheme goes through full planning from the start. That makes getting the early design and planning strategy right the most important part of the whole project.
Types
Which one suits you depends on the site, whether there's an existing dwelling on it, and how the local plan treats new housing in that location.
A new house built in the garden of an existing property, subject to access and amenity impact on neighbours.
Demolishing an existing house and building new in its place, usually on an already-established residential plot.
A new house on a gap site between existing buildings on a street.
A one-off house designed around a specific client brief, often on a larger or rural plot.
Two or more new dwellings on one site, sharing access and infrastructure.
| Extension type | Build cost | Time on site | Planning | Best suited to |
|---|---|---|---|---|
| Garden plot / backland | £2,200–£3,200 /m² | 20–28 weeks to decision | Full planning permission required | Gardens with separate access potential |
| Replacement dwelling | £2,000–£3,000 /m² | 16–24 weeks to decision | Full planning permission required | Existing plots being redeveloped |
| Infill plot | £2,200–£3,200 /m² | 20–28 weeks to decision | Full planning permission required | Gap sites on an existing street |
| Self-build | £2,400–£3,600 /m² | 20–30 weeks to decision | Full planning permission required | Larger or rural plots |
| Small residential scheme | £2,000–£2,900 /m² | 24–36 weeks to decision | Full planning permission required | Sites suited to multiple dwellings |
Costs
We don't build, and we take no margin on the build, so we've no reason to flatter these numbers. They are what Essex builders are quoting our clients in 2026.
Typical single new-build home
£2,500–£6,000 /m²
Around £350,000–£840,000 for a typical 140 m² detached home, built to a good standard. The range is wide because specification, plot and site conditions matter more here than on any other project type.
These figures are build cost only.
Ask three builders and you'll get three numbers. What matters is they're pricing the same specification. That is exactly what a proper technical package gives you.
Costs reviewed August 2026 · next review February 2027
What kind of home is it?
Detached
Semi-detached
Terraced
Bungalow
Our design fee
Not an hourly rate and not a percentage of the build. One figure covering survey, concept design, the planning application and the Building Regulations package, quoted after our first conversation.
Use the design cost calculatorWe price-check builders' quotes against the drawn specification and inspect work as it progresses. You don't have to take our drawings and go it alone.
Stage 5 · construction supportCosts
Answer a few quick questions about your site and we'll send you a ballpark design-fee range within one working day — no obligation, no sales call unless you want one.
Planning
Every new dwelling needs a full planning application, whatever the site. What matters is working through the feasibility questions properly before you commit to a design, so the application has the best possible chance.
New dwellings never fall under permitted development, whatever the site. Every new-build project — a single garden plot or a small scheme - goes through a full planning application, so the design and planning strategy at the very start matters more here than on almost any other project type.
Building Regulations
There's no existing structure to work around - everything from the foundations to the drainage strategy is designed from scratch for the whole plot.
Full site investigation and foundation design suited to the ground conditions, rather than working around what's already there.
Whole-building structural design, coordinated with the engineer from the earliest layout stage.
Full Part L compliance and, increasingly, additional energy standards — SAP calculations run alongside the design, not bolted on at the end.
Foul and surface water drainage strategy, often including sustainable drainage systems, designed from scratch for the whole plot.
The NSP Stages
Click into any stage for what happens, what you receive, and what comes next. Expect Stage 3 to run longer here than on other project types - new-build applications usually need more supporting evidence.
Honest, early advice on what's realistic for your property, budget and how you want to live.
Options on the table exploring layout, light and flow, so you can react to real ideas.
We prepare and submit the right application, designed to give your scheme its best chance.
The approved concept is developed into a coordinated, buildable set of drawings.
Our work
Every project starts as a drawing. These are ours: the plans, elevations and approvals behind the finished rooms.
Add gallery items to show project photos and drawing sheets here.
FAQs
No. Permitted development rights apply to alterations and extensions of existing buildings, not to creating a new dwelling, so every new-build project needs a full planning application regardless of the site.
Build costs typically range from £2,000 to £3,200 per m² depending on specification, though this varies more than any other project type - a simple shell-and-core build sits at the lower end, a highly bespoke self-build at the upper end and beyond.
Expect 16 to 26 weeks from first consultation to a planning decision, longer than alterations or extensions, since new-build applications typically need more supporting evidence - transport, drainage, ecology and design justification among them.
Sometimes, subject to access, amenity impact on neighbours, and how the council's local plan treats garden and backland development in your area - this is one of the first things we test at feasibility stage, honestly, before you spend on drawings.
It's demolishing an existing house and building new in its place. It can be more straightforward than a garden plot since there's already an established residential use on the site, though scale, design and impact on neighbours still matter.
For most new-build projects, yes - it's not compulsory, but it materially improves the odds of a smooth application, and we recommend it as standard for this project type.
Likely a structural engineer, and depending on the site, an ecologist, arboriculturist, drainage engineer or transport consultant. We coordinate this team rather than leaving you to assemble it yourself.
We work to a fixed fee agreed before we start, covering survey, concept design, the full planning application and Building Regulations package. Use the cost calculator for an indicative range, though new-build fees are typically quoted individually given how much sites vary.