What is a ‘wel’? (tile roll, stair nosing, spring)
“Wel” is an old Dutch building term with three meanings: the roll of a roof tile that laps over the neighbouring tile, the projecting part of a stair tread (the nosing) and a spring, a place where water wells up from the ground. The context shows which meaning is intended.
1. On roof tiles
On profiled tiles such as the Dutch pantile, the “wel” is the roll at the top of the wave that laps over the adjacent tile. This stops rain running between two tiles into the roof.
- Mind the laying direction: lay the tiles in the direction the manufacturer specifies. With a wrongly laid lap, rain can be driven under the roll.
- Broken roll: a chipped-off roll leaves an opening in the roof. Replace the tile.
2. On stairs
On a staircase, the “wel” is the nosing: the part of the tread that projects over the riser below. That is why the top piece at floor level is called a “welstuk” (landing nosing) in Dutch.
- The nosing increases the usable going without making the stair longer.
- A nosing that is too deep or sharp is a trip hazard when climbing. A slightly rounded edge is more comfortable and wears better.
- Loose or worn nosings can be protected with a stair nosing profile.
3. As a spring
A “wel” is also a place where groundwater rises to the surface by itself. The word survives in field names and in the verb “opwellen” (to well up), for example seepage on the landward side of a dike.
- Building on or near a spring requires extra attention to drainage, dewatering and watertight basements.
- Water welling up behind a dike during high water can signal seepage or internal erosion and should be reported to the water authority straight away.
Related terms
- Nosing
- Landing nosing
- Riser
- Tread depth
- Roof tile
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