Party wall monitoring
Independent monitoring of party walls and adjoining buildings during basements, underpinning, extensions and demolition, reported in a format that drops straight into the party wall award.
Why party wall works are monitored
Basements, underpinning and demolition next to a shared wall all carry a risk of movement in the neighbouring building. Monitoring gives the building owner, the adjoining owner and their surveyors an independent record of what actually happened, so concerns are dealt with on facts rather than opinion.
What we monitor
- Movement of the party wall and adjoining building, using total station targets read from a stable control network, typically to ±1mm.
- Cracks in the adjoining property, using Demec studs and tell-tales. See crack monitoring.
- Vibration at the boundary during piling or demolition. See vibration monitoring.
Reports built for the award
Every report shows movement against the previous reading and against the original baseline, with tables and graphs clean enough to go straight into the party wall file. Most of our party wall monitoring is in Westminster, Kensington and Chelsea, Camden, Hammersmith and Fulham, Wandsworth and Richmond, and we cover all 32 London boroughs.
How it works
Specification
We work to the monitoring requirements in the award, or help the surveyors and engineer write them.
Baseline
Targets and studs are installed and two baseline surveys are taken before any works begin.
Monitoring through the works
Visits follow the works programme, weekly during excavation and underpinning, then less often.
Close out
A final report records the movement over the whole project for the surveyors' files.
Who we work with
Party wall surveyors
Defensible data to discharge your duties under the Party Wall etc. Act 1996.
Building owners
Evidence that your works did not damage your neighbour's property.
Adjoining owners
Independent records of how your building behaved while the works went on next door.
What clients say
Read our reviews on Google★★★★★
We have used THS Concepts for multiple surveys from topographic to drone photogrametry, they are professional and prompt and deliver exactly what is requested. Highly recommended.
★★★★★
I contacted Tom to carry out a Topographic survey, and cannot recommend them enough. Nothing was to much, and I was kept up to date with everything as it happened! Great company to deal with and reasonably priced.
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Superb service, quick turnaround and extremely helpful! I wouldn't hesitate to use THS Concepts again if I need to in the future!
Party wall monitoring: common questions
When does a party wall award require monitoring?
Usually for basements, underpinning, deep excavations within 3 or 6 metres of a neighbouring building, and demolition. The surveyors and structural engineer decide what is needed, and it is written into the award.
When should monitoring start?
Before any works begin. A baseline taken after enabling works is not a true baseline. We take at least two pre-works surveys.
What triggers are typical?
Triggers should be set by the structural engineer. For London residential basements they are often around 5mm amber and 10mm red for total movement, with tighter values for sensitive or listed buildings.
What if a trigger is breached?
The named site contact is told the same day so works can be paused and reviewed. We do not wait for the next scheduled report.
Related services
- Measured building surveys
Floor plans, elevations and sections of existing buildings.
- 3D laser scanning
Point clouds and BIM models of buildings, plant and structures.
Tell us about your site
Send a location, a rough brief and your deadline. We reply with a fixed quote within 24 hours.