Self-Build House Guide UK — Planning, Costs & Mortgages
A complete guide to building your own house in the UK — from finding land and getting planning permission to self-build mortgages, costs, and project management.
·4 min read
Building your own home gives you complete control over design, layout, and specification. Here’s everything you need to know about self-building in the UK.
Self-Build Overview
Feature
Detail
Average build cost (excl. land)
£1,500–£3,000/sqm depending on spec
Average UK self-builds per year
~12,000–15,000
Typical build time
12–24 months (after planning)
VAT reclaim
Yes — on new builds
CIL exemption
Yes — self-builds exempt from Community Infrastructure Levy
Right to Build register
Local councils must keep a register of people wanting to self-build
Typical Costs
Build Cost per Square Metre
Specification
Cost/sqm
100 sqm house
150 sqm house
200 sqm house
Basic
£1,500–£1,800
£150,000–£180,000
£225,000–£270,000
£300,000–£360,000
Good
£1,800–£2,200
£180,000–£220,000
£270,000–£330,000
£360,000–£440,000
Excellent
£2,200–£2,800
£220,000–£280,000
£330,000–£420,000
£440,000–£560,000
Outstanding
£2,800–£3,500+
£280,000–£350,000+
£420,000–£525,000+
£560,000–£700,000+
Full Project Budget
Cost element
Typical range
Notes
Land
£50,000–£500,000+
Huge variation by area
Build costs
£150,000–£400,000
Based on size and spec
Professional fees (architect, engineer, project manager)
10–15% of build cost
£15,000–£60,000
Planning permission
£462 (current fee for a new dwelling)
Plus any pre-application advice
Building regulations
£500–£2,000
Depends on council and project size
Warranty (structural)
£1,500–£3,500
NHBC, LABC, Premier Guarantee, etc.
Site preparation
£5,000–£30,000
Demolition, access, services
Utilities connections
£5,000–£20,000
Water, electric, gas, drainage
Landscaping
£5,000–£30,000
Driveway, garden, fencing
Contingency (10–15%)
£15,000–£60,000
Essential — unexpected costs always arise
Total
£250,000–£1,000,000+
Depends on land, location, size, specification
Finding Land
Source
Detail
Plotfinder.net
Largest UK self-build plot database
Rightmove/Zoopla
Search for “land” or “building plot”
Local estate agents
Some specialise in land sales
Auction houses
Land plots often sold at auction
Local council Right to Build register
Register your interest — councils must provide plots
Direct approach
Identify potential plots and approach landowners directly
Local newspaper classifieds
Occasionally list plots
What to Check Before Buying Land
Check
Why
Planning history
Has planning been granted or refused before?
Title deeds and covenants
Any restrictions on building?
Access
Is there legal access to the plot?
Services
Are water, electricity, gas, drainage available or do they need connecting?
Ground conditions
Get a soil survey — bad ground can add £10,000+ to foundation costs
Flooding
Check the flood risk map
Trees
TPOs (Tree Preservation Orders) can restrict what you build and where
Contamination
Previous industrial use may mean costly remediation
Neighbours
Talk to them — any boundary disputes?
Planning Permission
Stage
Detail
Cost
Pre-application advice
Informal discussion with planning officer
£50–£600
Outline planning
Establishes the principle of building (not detailed design)
£462
Full/detailed planning
Detailed plans for assessment
£462
Decision time
Typically 8–13 weeks
—
Planning conditions
You’ll need to satisfy conditions before and during build
—
Self-Build Mortgages
Feature
Arrears stage
Advance stage
When funds released
After each stage is complete
Before each stage begins
Cash needed upfront
Yes — you fund each stage then get reimbursed
No — funds released to start each stage
Interest rate
Lower
Higher (typically 0.5–1% more)
Best for
Those with savings/cash reserves
Those who need funds to start each stage
Number of stages
4–6
4–6
Typical Release Stages
Stage
% of build cost released
Land purchase
Separate land mortgage or deposit
Foundations
15–20%
Wall plate (walls built to roof level)
15–20%
Wind and watertight (roof on)
15–20%
First fix (plumbing, electrics, plastering)
15–20%
Second fix (kitchens, bathrooms, finishing)
10–15%
Completion
Final release / retention
Self-Build Mortgage Lenders
Lender
Type
Notes
BuildStore
Broker/portal
Largest self-build specialist — access to multiple lenders
Ecology Building Society
Direct
Specialises in sustainable and self-build
Bath Building Society
Direct
Self-build and custom build mortgages
Furness Building Society
Direct
Self-build products
Mainstream lenders (e.g. Halifax, Nationwide)
Limited
Some offer self-build but criteria can be restrictive
Build Routes
Route
You manage
Cost
Control
Risk
DIY build
Everything yourself
Cheapest
Maximum
Highest (quality, time, safety)
Self-manage with subcontractors
You hire individual trades
Lower
High
Medium
Main contractor
One builder manages everything
Mid–higher
Medium
Lower
Project manager + subcontractors
PM manages trades for you
Higher (PM fees 10–15%)
Medium
Lower
Package/kit home supplier
Pre-designed home erected on your plot
Variable
Lower (limited design changes)
Lower
Turnkey
Developer does everything, you get a bespoke home
Highest
Lower
Lowest
VAT Reclaim
Detail
Information
Who can claim
DIY housebuilders building a new dwelling
What you can claim
VAT on building materials and some contractor services
When to claim
Within 3 months of completion (HMRC may extend if asked)
Form
VAT431NB (new build)
How much
Typically £5,000–£30,000+
What you need
All VAT invoices (must be in your name)
What you can’t claim
Professional fees (architect, engineer), tools and plant hire, furniture/soft furnishings
Insurance You Need
Insurance
When
Why
Site insurance
During construction
Covers theft, damage, public liability
Structural warranty
Before completion
Required by most mortgage lenders — 10 years
Self-build insurance
Throughout
Combines site insurance, employer’s liability, public liability