What is a rafting mark?
A rafting mark is a mark scratched or cut into timber while it was being transported in a raft over water. The mark showed who owned the wood. It is a variant of the assembly mark, the sign carpenters used to number the parts of a structure. In old roof structures and floor joists, rafting marks can sometimes still be recognised. In Dutch it is called a vlotmerk.
Background
For centuries, building timber was transported along rivers. Logs were tied together into rafts that drifted downstream. In this way, conifer wood and oak from German forest regions, among others, reached the Netherlands via the Rhine, where Dordrecht was an important timber market. A single raft carried wood from several owners. With a rafting mark, each party could find its own logs after arrival.
Rafting holes and rafting pegs
To link the logs, a hole was made in each log and in a cross timber. Twisted twigs or rope were inserted and clamped with a driven-in wooden peg, the rafting peg. In old beams you can sometimes still see such a peg, which looks like a dowel, or just the empty rafting hole.
Why is it interesting?
- Building history: a rafting mark or rafting hole shows that the timber arrived by water. Combined with dendrochronology, this can say something about origin and dating.
- Recognising reuse: a rafting hole in an odd place is normal and need not indicate an earlier joint or reuse.
- Restoration: keep and document such traces. Do not fill a rafting hole without reason; it is not a defect.
Tips for examining old beams
- Inspect the beams with raking light (a torch held at a low angle across the surface); scratched marks become much more visible.
- Photograph each mark with a measuring rod next to it and note its position in the structure.
- Distinguish rafting marks from assembly marks: assembly marks are usually located at a joint and appear in pairs on both parts.
Related terms
- Mark
- Dendrochronology
- Dowel
- Beam timber
- Wood joints
- Roof truss
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