A slate hammer, or slater’s hammer, is the combined hand tool with which a slater trims slates to size, punches holes for the fixings, and drives or draws nails. It is not an ordinary hammer but four tools in one, made for working on a roof plane where there is no bench beside you.
The hammer generally weighs somewhere between 400 and 800 grams — light enough to work with all day and not break a slate, heavy enough to drive a nail into the boarding.
The parts and what they do
- The spike on one side of the head punches the hole for the slate nail. It is driven from the underside of the slate upwards, so that the breakout on top forms a small funnel in which the nail head sits recessed. Without that recess the slate above rocks on the nail head.
- The striking face on the other side drives the slate nails into the timber.
- The pear- or keyhole-shaped opening in the middle of the head is for pulling nails — indispensable in repair work.
- The chamfered sides of the shaft form the cutting edge with which the slate is trimmed. Some patterns are made specifically left- or right-handed; choose the one that suits your working hand.
Working with a cutting iron
Trimming is almost always done together with a slate cutting iron (also called a slate stake or cutting bench): a steel edge or block fixed to the eaves or to a support, over which the slate is laid. The slate projects beyond the edge, the hammer’s cutting edge chops along it, and the edge acts as both guide and backing.
This produces the characteristic slightly bevelled edge of a hand-dressed slate: wider on the underside, so water runs off rather than creeping inwards. That is not an aesthetic accident but a functional property — a square saw cut does not give you it.
Practical tips
- Always dress with the correct face of the slate upwards. The bevel belongs on the underside; dressed the wrong way round, the edge draws water inwards.
- Punch the nail hole only after the slate is cut to size. Otherwise the hole ends up in the wrong place.
- Do not use an ordinary claw hammer. A normal hammer has no spike, no cutting edge and too broad a face; slates break uncontrollably under it.
- Keep the spike sharp. A blunt spike shatters the slate around the hole instead of punching cleanly through.
- Work safely on the roof. Use a ladder with a ridge hook and proper fall protection; slate is slippery and not walkable.
- For drawing fixed nails beneath a slate in place, the slater reaches for a slate ripper, which suits the job better than the opening in the hammer head.
Related terms
- Slate roof
- Slate hook
- Roof slate
- Hammer
- Claw hammer
- Roof boarding
- Roof pitch
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