NDM Surveys
Recording position and elevation on high-risk projects
Capture the exact position and elevation of surrounding buildings relative to NAP.
For construction projects involving preloading, sheet piling or dewatering, the positions and elevations of surrounding buildings must be recorded with precision. In an NDM survey we determine the X, Y and Z coordinates of all relevant objects relative to NAP (Normaal Amsterdams Peil, the Dutch national height reference). This provides a reliable reference to detect any later movement.
The process starts with a baseline measurement: the exact position and elevation of all relevant buildings and structures in the project area is recorded. This baseline is the reference. During periodic re-measurements we compare new values with the baseline to determine whether any height differences have occurred.
NDM surveys are mandatory in many Dutch municipalities for high-risk projects. We perform the measurements in line with applicable guidelines and deliver reports that meet the requirements of clients and authorities.
Equipment & software
What you can expect.
Baseline measurement of all objects in the project area
Periodic elevation measurements in line with guidelines
Alerts when threshold values are exceeded
Final report comparing baseline and final measurement
FAQ.
The most asked questions about NDM Surveys. Question not listed? Feel free to get in touch.
Many municipalities require NDM for projects involving preloading, sheet pile work, dewatering or heavy earthworks near existing buildings. The exact requirement varies per municipality and project.
NDM focuses specifically on elevation differences for buildings within a project area, often as a condition of a building permit. Deformation monitoring is broader and also measures horizontal displacements of structures, dikes and other objects.
Preloading (raising terrain), installing sheet piles, dewatering (lowering groundwater) and heavy earthworks. These activities can cause surrounding buildings to shift in elevation.
The field survey is processed the same day. When threshold values are exceeded we contact you immediately. The formal report follows within a few working days.
“We are very satisfied with the dimensional control service across various projects. From the very first contact, communication has run smoothly.”
“Michael had everything worked out the day before and was able to come the very next day. Delivers good work and is professional. We are very satisfied.”
“The dimensional control service was excellent. The team delivered accurate and timely results, which kept the project running smoothly.”
Related services.
Deformation Monitoring
Detect settlement before damage occurs. Periodic measurements at quay walls, bridges and industrial structures give you timely insight.
Precision Leveling
Get reliable elevation data accurate to a tenth of a millimeter. For foundations, floors and structural calculations, referenced to NAP.
24/7 Monitoring
Keep watch over your project day and night without anyone on site. Immediate alerts on deviations, continuous insight into movement.
More about NDM Surveys?
We are happy to discuss the options for your project. Reach out to Michael for personal advice, no strings attached.
No-obligation advice on the approach for your project. Usually a response within 24 hours.