Stone slab crating: granite, marble and quartz

Slabs stand on edge

A stone slab is brittle in bending, and a large piece with a natural fissure will snap if it sags. On edge, it carries its own weight along its length. We stand slabs on a padded ledge on the skid and lean them against the back frame, one against the next, in bundles that the yard can lift with a forklift or a crane.

Stone is heavy, and a short stack of thick slabs reaches a gross weight that calls for a strong skid. We ask for the slab size, thickness and count, then size the runners and the base deck to match.

Between slabs and against the frame

Polished faces scratch from grit and from touching other slabs. We separate each slab with foam, cork or paper pads, placed at corners and along the middle so the faces never meet. Pairs of slabs that were cut from the same block can be bundled face to face with a matched pad, which keeps the veining sequence for an installer.

Rubber or felt sits at every point the stone meets timber. Raw wood leaches tannins that stain marble and light limestone, so we put a barrier film or tape between stone and any untreated board.

• Edges polished or raw, protected with corner guards
• Engineered quartz slabs kept dry and flat on the A-frame
• Resin-filled slabs shaded from heat
• Sink cut-outs braced with board so the slab does not crack across the opening

Strapping the stack

The bundle is strapped to the A-frame with ratchet straps or steel banding, run over edge guards and pulled tight enough to stop the stack moving but not enough to crush the corners. Straps cross the stack at the quarter points, and a diagonal strap resists sliding.

Blocks of hardwood wedge the bottom edges against the skid and keep the stack from walking along the ledge. After a trip of any length, straps loosen, so the receiver checks them before releasing the stack.

Cut pieces, vanities and fabricated tops

Fabricated countertops, vanity tops and cut-to-size pieces with polished edges are crated differently from full slabs. They travel on edge in a smaller frame or in a cleated plywood box, with each piece padded and a sink cut-out reinforced with a board across the opening.

Thin porcelain and ultra-compact panels flex and chip at corners. A rigid backing board supports the long side, and a pair of end rails holds the panels from slipping.

Moisture, resin and cold

Natural stone absorbs water through its edges and back. A wet slab stacked tight can stain and, if it freezes, spall. We keep slabs dry before loading, cover the stack in film with a vent at the top, and add desiccant to the container when the route is long.

Resin-filled and epoxy-treated surfaces soften in direct heat. A bundle that will sit on a dock in strong sun gets a reflective cover, and the lid carries a note to keep it out of the heat where a choice exists.

Lifting and orientation

Slab crates are heavy and top-heavy at the lean. The skid is built for forklift entry from the long side, and sling points are marked on the A-frame for a crane. The centre-of-gravity mark is painted on two faces, since the mass sits away from the centre when the stack is leaning.

ISO 780 marks for fragile and this way up, with a clear arrow showing the base, go on all sides. A tip indicator on the end panel tells the receiver if the crate was laid down. Slab crates are never double-stacked.

Export, containers and yards

A-frame crates for slabs load into a container with the skid width matched to the door. Bundles are blocked at the doors so the container floor cannot see a shift. For export, the lumber is heat-treated and carries the IPPC stamp. Check the destination plant-protection authority for the rule that applies to your shipment.

We keep the crate spec on file, so a distributor shipping the same slab size every month gets the same frame and the same strapping.

Unloading at the yard

A receiving yard needs to see how the bundle is held before cutting a strap. We paint the strap positions on the A-frame and mark the release order on the end panel: front straps first, then the rail, then the back. A slab released out of order can fall as a block.

We suggest the yard use a slab clamp or a vacuum lifter and place the A-frame on firm, level ground. The crate drawing and the strap plan travel with the shipment, tucked in a sleeve on the end panel.