What is a trotseerloodje?
A trotseerloodje is a small, flat, folded piece of lead in the shape of a shield, soldered over a nail that fixed lead or zinc to a roof or wall. It seals the nail hole so water cannot run down the nail, keeps the nail from rusting and stops the wind lifting the lead strips. The word is Dutch and has no established English equivalent; descriptively you could call it a lead nail cap or soldered lead dot.
Uses
You will find trotseerloodjes on historic roofs with leadwork, mainly in the Netherlands and Flanders:
- Slate roofs: at the eaves and along nailed lead details.
- Dormers: on the lead cladding of the cheeks.
- Ridges and valleys: wherever lead or zinc was fixed with nails.
A plumber’s calling card
Plumbers often cast these pieces themselves and marked them with their name or initials, sometimes a date and often a picture of their tools, so they worked as a maker’s mark. The oldest known examples date from the late 16th century. Museum De Lakenhal in Leiden holds cast examples from the 17th and 18th centuries showing a roofer’s hammer and a suction pump above the maker’s initials, each about 7 by 5.5 centimetres.
Practical tips
- Do not throw them away: a trotseerloodje is a historic building fragment. Keep it even if the leadwork itself must be renewed.
- Record before stripping: photograph the location, note any initials and date, and report the find to the local heritage officer. A date can help to date earlier roof repairs.
- Listed building? Ask first: alterations to the roof of a protected building usually need consent. Agree in advance how historic parts will be handled.
- Reuse is possible: old pieces can be soldered back during restoration, or a specialist heritage plumber can cast replicas.
Related terms
- Sheet lead
- Roof lead flashing
- Lead replacement flashing
- Lead bossing
- Slate roof
- Dormer
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