What is an LSBUD search and is it free?

LSBUD, LineSearch Before You Dig, is a free online search where you draw your site boundary on a map and it tells you which utility networks have recorded apparatus near your plot, then routes you to each owner for detailed plans. Some plans arrive within minutes, others take a few working days, which is why you run it early in pre-construction.

What is a CAT and Genny used for?

A CAT (Cable Avoidance Tool) is a handheld receiver that detects buried cables and metallic pipes, and the Genny is a signal generator that applies a tone to a specific line so the CAT can trace its exact route and rough depth. Together they locate services on the ground that the record plans only indicate.

Does an LSBUD search find private cables and pipes on my own land?

No. LSBUD only covers the registered public and utility networks, not the armoured cable to a garden office, a supply to a detached garage, an old lead water pipe, or a capped drain under a former patio. These private services are the ones that injure homeowners because no public search will ever show them.

What should I do if I strike a gas pipe while digging?

Stop work, keep everyone clear with no naked flames or smoking, and call the National Gas Emergency Service on 0800 111 999 immediately, even if no gas appears to be escaping. The line is free and runs 24 hours, and calling is the right move whether or not you think there is a leak.

Why can a plastic gas or water pipe be missed by a detector?

A plastic pipe with no tracer wire is not metallic and carries no current, so it returns almost nothing on any CAT mode. Yellow plastic gas service pipe is the classic example, and the only reliable way to find it is to dig for it carefully by hand.

Locating Underground Services Before You Dig: LSBUD, CAT & Genny (2026)

The cheapest insurance on your entire build costs nothing and takes a few minutes online. The most expensive mistake on the whole project can happen in the first hour of digging, before a single brick is laid, and it can kill the person holding the spade. Both involve the same question: what is buried under the ground you are about to break open?

A homeowner planning a rear extension thinks of the dig as the easy bit. Clear the patio, get a digger in, scoop out the trench. But under that patio there may be the gas service feeding the house, the electricity cable that powers it, the incoming water main, and a telecoms duct, any of which the previous owner, the original builder, or a tired groundworker put exactly where you now want to excavate. Hit the wrong one and the consequences run from an inconvenient broadband outage for the street to a fatality.

This task comes first in groundwork for a reason. You settle what is under the plot before you mark the footprint and long before you dig the trench.

Do this first

This is the first physical task in groundwork, and it gates everything that follows. The desktop search has no hard prerequisite, so start it early in pre-construction: plans can take several working days to arrive. The on-site scan and trial holes happen immediately before excavation. Both must be done before the dig. Once you know where services run, you can set out the footprint clear of them, then dig the foundation trench safely. Get this wrong and the rest of the build does not get its safe start.

Locating Underground Services Before You Dig

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