Vibration from construction and BS 6472 response levels

Vibration that people find intolerable is roughly an order of magnitude below the level that damages an ordinary house. That gap is the whole subject. Almost every construction vibration complaint is about annoyance, almost every claim that follows is about damage, and the assessment has to answer both questions with different criteria and different units.

Get the two mixed up in a construction method statement and the document falls apart on the first reading, because an environmental health officer assessing disturbance has no use for a peak particle velocity limit set to protect brickwork.

Human response and building damage are different questions

Building damage is assessed as peak particle velocity, in millimetres per second, measured at the foundation or the ground floor of the receiving structure. The guide values in the British Standard on evaluation and measurement of vibration in buildings vary with frequency and with construction type, and they are set to avoid cosmetic damage, meaning hairline cracking in plaster rather than structural failure. Unreinforced masonry and older buildings take lower values than reinforced or framed structures.

Human response is assessed differently. The British Standard on human exposure to vibration in buildings uses a vibration dose value, which accounts for magnitude and for how long the exposure lasts across a day or a night period. That approach exists because a short burst and a continuous hum affect people differently even at the same peak.

The practical consequence for a developer is that you will usually be constrained by the human response criterion, not the damage criterion, on any site with residential neighbours. Designing to the damage limits alone produces a method statement that is technically compliant and socially unusable.

What peak particle velocity limits mean in practice

The published guidance on construction vibration also describes the effects on people at different magnitudes. Values well below one millimetre per second are around the threshold of perception in a residential setting. A little above that, vibration is clearly felt and complaints become likely. By the time levels reach the tens of millimetres per second, the exposure is intolerable for anything but the briefest duration, and that is still below the level at which cosmetic damage to a normal building would be expected.

Two caveats matter. Listed buildings, structures already in poor condition and buildings with sensitive contents or equipment justify lower limits than the standard guide values, and that is a matter for a structural engineer rather than a default. And the values relate to the structure, so a measurement taken on soft ground twenty metres away does not tell you what is happening at the party wall.

Where a neighbour operates vibration sensitive equipment, laboratory instruments, imaging equipment in a clinic, or precision manufacturing, the relevant limits come from the equipment manufacturer and can be far lower than anything in the building standards.

Piling and groundworks ranked by what they produce

The method chosen for piling and ground improvement dominates the vibration output, and it is the one variable still available once the site layout is fixed.

Breaking out slabs and foundations deserves attention because it is routinely left out of the assessment. It happens early, close to boundaries, and it produces the transient events neighbours notice first.

Where percussive methods are unavoidable, the usual controls are a trial pile with monitoring before the main works, restricted hours, a maximum number of blows per period, and an agreed stop and review procedure.

Monitoring regimes and trigger levels

Monitoring is worth doing properly or not at all. A useful regime has continuous triaxial monitoring at the structures identified as sensitive, a baseline period before works start so background events are understood, and trigger levels set below the limit rather than at it.

Use two triggers. An amber level prompts a review of the method by the site team and a note in the record. A red level stops the activity until the method is changed and agreed. Write down who has authority to stop work, because a trigger with no named person behind it gets acknowledged and ignored.

Automated alerting by text or email at the point of exceedance is standard and inexpensive. Weekly reporting to the council, where a condition requires it, should include the exceedances and what was done, not a summary saying the works complied.

Set the monitoring locations with the neighbours' agreement where possible. A monitor inside a complainant's property, with data they can see, resolves more disputes than any amount of correspondence.

Condition surveys of neighbouring property

A pre-works schedule of condition of neighbouring buildings is the best value insurance on the job. It is not a planning requirement, and nobody can force a neighbour to allow access, but it changes the shape of every subsequent argument.

Commission an independent surveyor, record internally and externally with dated photographs and video, note every existing crack with a measurement, and give the neighbour a copy. Where access is refused, record the external condition from your own land and write to the neighbour confirming that access was offered and declined.

Crack monitoring using tell-tales across existing cracks, read at intervals, converts an argument about whether a crack is new into a record of whether it moved.

The Party Wall etc. Act 1996 runs a separate process for excavation and works near neighbouring structures, with its own notices, surveyors and awards. It is not part of the planning application and it is not covered by planning conditions, but the timing has to be built into the programme because notice periods are fixed.

What planning can and cannot control

Planning conditions can require a construction method statement, a monitoring regime, restricted hours, and the approval of a piling method before works begin. That is a real set of controls and it is where most vibration mitigation is secured.

What planning cannot do is resolve damage to a third party's property, which is a civil matter, or authorise a statutory nuisance. Vibration is included in the statutory nuisance regime under the Environmental Protection Act 1990, and sections 60 and 61 of the Control of Pollution Act 1974 cover vibration alongside noise, so a prior consent application can fix the vibration terms as well. Our note on what a planning condition cannot fix sets out that boundary, and the companion piece on construction vibration under BS 5228 and BS 6472 in practice goes into the assessment method.

PlanScope does not produce a vibration assessment. That work sits with a specialist acoustic or geotechnical consultant, and it should be commissioned as such. What a Construction Management Plan drafted in PlanScope can do is set out the method, the hours, the monitoring commitments and the complaints procedure, referencing the specialist assessment rather than replacing it. Where the condition of a neighbouring structure is in question, a Structural Survey is the document that records it, and councils expect a suitably qualified author.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.