Beginner

Utility connections: water, electricity, drainage

05/04/2026 11 min read

You’ve found your plot and exchanged contracts. But before you pour the first foundation, you need to connect the utilities. Mains water, electricity, drainage, broadband — each connection has its own process, lead times and costs. Misjudge them and your build can stall for months. Here is the complete guide, utility by utility, so nothing catches you out.

The order of connections

The sequence matters — some connections must happen before the build starts, others during or after.

Utility	When	Why
Mains water	Before the build	You need it for concrete, cleaning, site welfare
Electricity (temporary)	Before the build	Powering tools, mixer, lighting
Drainage	During groundworks	Foul/surface water pipes go in before the slab
Electricity (permanent)	After watertight	Connection to consumer unit, Part P certificate
Broadband / fibre	After weathertight	Cable pulled to the house
Gas (if applicable)	After weathertight	Gas network connection

Tip — Submit your connection applications as soon as you get planning permission. Your DNO and water company can take 2–4 months to respond. Wait until the build starts and you risk having no water or power during the foundations.

Mains water connection

The process

Contact your water company (your area’s statutory supplier — check the Consumer Council for Water website).
Submit a new connection application — you will need the planning permission reference and a site plan.
The water company issues a quote within 2–4 weeks.
Works are carried out by the water company (trench from the main to your boundary + meter).

What is included and what is not

Included in the connection	Your responsibility
Trench from the public main to your boundary	Trench from your boundary to the house
Meter + meter chamber	MDPE pipe from boundary to house
Stop tap	Internal pipework

Costs

Situation	Cost
Main runs along the boundary	£700–£1,800
Main crosses the road	£1,800–£3,500
Extension required (> 100 m)	£3,500–£13,000+

Lead time: 4–8 weeks after accepting the quote.

Temporary site water supply

You need water on site from day one. Two options:

Early permanent connection: apply far enough in advance so it is in place before groundworks start.
Bowser + pump: a temporary solution if the connection is not ready. Cost: bowser hire ~£90/month.

Electricity connection (DNO)

The process

Question

The DNO connection happens in two stages:

1. Temporary supply (site)

Apply via your DNO’s website (UK Power Networks, Western Power Distribution / National Grid, Northern Powergrid, Scottish Power Energy Networks, SSE, etc.)
Capacity: a 60A / 14 kVA single-phase supply is usually enough for a site
The DNO installs a temporary cut-out at the plot boundary
Lead time: 2–6 weeks
Cost: £450–£1,400

2. Permanent connection

Apply after your Part P certificate (electrical installation certificate from a registered electrician)
The DNO connects the permanent meter box to the network
Lead time: 2–10 weeks after the Part P certificate
Cost: included in the initial connection or £450–£1,400 extra if the arrangement changes

DNO connection costs

Distance to network	Single phase (≤ 80A)	Three phase / higher
< 30 m	£1,350–£2,200	On application
30–250 m	£2,200–£7,000	On application
> 250 m (extension)	£7,000–£22,000+	On application

Warning — If your plot is far from the network (> 250 m), the DNO may charge a network extension contribution. This can run to tens of thousands of pounds. Get a quote before buying the plot — it can be a deal-breaker. See our article on assessing plot viability.

The meter box / cut-out

The DNO installs a meter box at your plot boundary. This is the point of supply:

Cut-out and meter box: contains the service fuse and, after the permanent connection, the electricity meter.
Location: at the plot boundary, accessible from the public highway (the DNO must be able to reach it without entering your property).
Height: typically 450 mm–1,350 mm from ground level.

Drainage connection

Two scenarios depending on whether your plot has access to a public sewer.

Mains drainage (public sewer)

If a public sewer runs past your plot:

Apply to connect via your sewerage undertaker (e.g. Thames Water, Severn Trent, Anglian Water).
Works: they install an inspection chamber at the boundary + a connection to the sewer.
You lay the drain from the house to that chamber (foul water and surface water separated or combined depending on the sewer type).

Item	Cost
Boundary inspection chamber	£450–£1,350
Connection to public sewer	£1,350–£3,500
Private drain on your plot	Your cost (~£27–£45/m)
Infrastructure levy (varies by council)	£900–£4,500

Private drainage (no public sewer)

If no public sewer is available, you must install an on-site sewage treatment system. This is covered in detail in our dedicated article on private drainage and septic tanks.

In summary:

System	Cost	Space needed
Septic tank + drainage field	£4,500–£7,000	Large (permeable ground)
Septic tank + sand filter	£6,000–£10,500	Medium
Package sewage treatment plant	£7,000–£13,000	Small
Compact filter unit	£7,000–£10,500	Small

Good practice — Contact your building control drainage officer before buying the plot. They will tell you which system suits your soil and provide technical requirements. This is free and compulsory for any notifiable drainage work.

Broadband and fibre connection

Fibre broadband

On a housing development: fibre is usually brought to the plot boundary by the developer.
Standalone plot: contact the infrastructure operator for your area (Openreach, CityFibre, or your area’s alt-net). A standard fibre connection is free for the occupier (subsidised by the operator).
Lead time: 4–18 months depending on coverage and whether a new build notice is needed.

Legacy copper phone line

Being phased out — Openreach is progressively closing the copper network. Do not rely on it for a new build.

No fibre available?

In areas with poor coverage, consider:

4G/5G home broadband: EE, Vodafone, Three and others offer fixed wireless plans. Speed: 30–300 Mbps.
Starlink: satellite internet. Speed: 50–200 Mbps. Cost: ~£40/month + £450 for hardware.

Gas connection (if applicable)

Conseil

A gas connection is not essential for a new build — heat pumps and electric heating are entirely viable and code-compliant. But if you want gas:

Apply: contact your local gas network operator (Cadent, SGN, Northern Gas Networks, Wales & West Utilities)
Cost: £350–£900 if the main runs along the boundary
Lead time: 3–6 weeks
Requirement: only a Gas Safe registered engineer may carry out the final connection. No self-build on gas pipework.

Tip — On a new build, gas is increasingly hard to justify: UK building regulations push towards low-carbon heating. Choose an air-source heat pump + hot water heat pump instead. You save the gas connection cost and avoid future tariff rises.

The ideal connections timeline

flowchart TD A[Planning granted] --> B[Apply for water + temp electricity] B --> C[Apply for drainage + fibre] C --> D[Build starts - water + power available] D --> E[Lay foul/surface drains during groundworks] E --> F[Watertight: apply for permanent electricity] F --> G[Part P issued: DNO permanent connection] G --> H[Fibre pulled + broadband live] style A fill:#0F4C81,stroke:#0F4C81,color:#fff style B fill:#F58220,stroke:#F58220,color:#fff style C fill:#F58220,stroke:#F58220,color:#fff style D fill:#56C6A9,stroke:#56C6A9,color:#fff style E fill:#FDFCF9,stroke:#C67A3C,color:#0F4C81 style F fill:#FDFCF9,stroke:#C67A3C,color:#0F4C81 style G fill:#56C6A9,stroke:#56C6A9,color:#fff style H fill:#56C6A9,stroke:#56C6A9,color:#fff

Cost summary

Utility	Typical range	Average lead time
Mains water	£700–£13,000	4–8 weeks
Electricity (temp + permanent)	£1,350–£22,000	2–10 weeks
Mains drainage	£1,800–£5,400	4–8 weeks
Private drainage	£4,500–£13,000	2–4 weeks (installation)
Broadband / fibre	£0 (free)	4–18 months
Gas (optional)	£350–£900	3–6 weeks
Total servicing	£4,500–£22,000+

Factor these costs into your total build budget from day one.

Key takeaways

Utility connections are not a footnote — they are a major budget line and a critical scheduling factor. Apply as soon as planning is granted, price every connection before you buy the plot, and arrange temporary water and electricity before the build starts. An unserviced plot can cost £22,000 more than a ready-serviced one — and that changes your total budget.