What is street level?

Street level, or road level, is the height at which the public street in front of a plot has been built and is maintained, expressed relative to a national height datum. In the Netherlands this is a formally fixed value called the straatpeil, given in metres relative to NAP, the Dutch height datum. In the UK the equivalent reference would be Ordnance Datum.

Street level is not the same as the site datum on your drawings. The datum (±0.000) is the zero point of your own building, usually the top of the finished ground floor. Street level is a given from the public realm that your plot has to connect to: the driveway, the threshold and the drainage all have to work with it.

Why it matters

In Dutch practice street level carries legal weight. Many municipal plans define the point from which building height is measured as follows: if the main entrance of a building directly borders the road, the reference is the height of that road at the main entrance; if it does not, it is the ground level at that entrance once construction is complete. Some Dutch municipalities, such as The Hague, require the street level at the boundary between street and plot to be formally set before new build or renovation along a public road.

Official and actual street level can also differ. On soft ground, roads subside over time, so the street you see may sit lower than the level the authority will eventually restore it to.

In practice

1. Get the official street level before you design. You need it for floor level, threshold height and permitted building height.
2. Set the ground floor high enough above the street so that surface water runs away from the building in heavy rain.
3. Allow for settlement. Give paths and driveways enough fall towards the street.
4. Read the planning definition word for word. Measure building height from the reference the local rules specify, not automatically from your floor.

Common mistake: designing to today’s subsided road surface. If the road is later raised back to its official level, your floor or threshold ends up too low.

Related terms

• Datum level
• Ground level
• NAP (Dutch height datum)
• Absolute settlement
• Surface water
• Zoning plan

Want to know more about building terms? Visit our knowledge base at fredsdiyplans.com.