Crating paintings and framed art

The inner travel frame

Nothing touches the painted surface. A canvas is held by its stretcher bars in a travel frame with a rigid backing board, and the front is covered with a glassine or acid-free tissue before a protective board is fitted. A framed work, meanwhile, is held by its frame edges, not by the glazing or the mat.

The inner box is closed and sealed. We line it with a moisture barrier and pack buffering material, so the air around the work stays at a steady humidity while the outer crate faces rain, sun and a shift from one climate to another.

Glass, acrylic and frames

Glazing is the weak point of a framed work. Broken glass scratches pigment, and a frame with a loose sheet of glass becomes a blade. Glass is taped in a grid pattern with low-tack film, or replaced with a temporary board in the frame, and a spacer holds the face board off the glazing.

Acrylic scratches when it is dry-wiped and it picks up static, so we avoid tissue touching it. Ornate gilt frames are protected at the corners and at every projection with moulded foam, since the frame's own ornament is often its most fragile feature.

• Corner guards on every framed edge
• Painted edges covered with a barrier layer
• Hanging wires removed or tucked behind the frame
• A condition report photograph packed outside the inner box

Climate and moisture

Wood panels, canvas and paper respond to humidity. A sealed inner box with a buffering material, such as conditioned silica gel or a buffered board, helps hold a stable relative humidity inside. Plain desiccant dries the air, which can harm old paintings, so the choice of buffer is something we ask the shipper or conservator to specify.

We add a humidity indicator card that can be read through a window. For a work going through a hot dock, the outer crate is lined with a barrier film on its skin, and the lid is sealed against rain.

Opening a crate on arrival

An art crate is designed to be opened by a handler with a screwdriver, not a pry bar. Screws replace nails on the lid, which is marked with an arrow showing which edge lifts, and the inner box is released by a second set of fasteners so the work is never dragged out sideways.

We suggest the receiver let the crate rest unopened in the display room for some hours so the contents match the room before the seals are broken. A condition report form can travel in a pocket on the outside, in a plastic sleeve, for the preparator to fill in as the work comes out.

The outer crate

The outer crate is a sheathed plywood box on a skid. Foam or cushion blocks hold the inner case clear of the walls on all sides, so an impact on the crate does not travel straight to the work. The inner box is held on the cushion, not screwed to the crate.

Large canvases can go in a long crate with a strongback across the top to stop flex. Our sheathed crates page shows how the panels are framed, and a multi-work shipment can have partitions inside one large crate.

Handling marks and indicators

Art crates carry ISO 780 symbols: fragile, this way up, keep dry, do not stack. A centre-of-gravity mark and a clear label for the open side tell a preparator which face holds the lid. Handling instructions, such as hand-lift only and the number of handlers needed, are printed on the lid.

A tip indicator and a shock indicator are attached at a visible spot. A change in either one means the work should be inspected on arrival, before the crate is moved indoors or opened, and the photograph of the indicator state is kept on the shipment record.

Export, customs and repeat crates

The skid and framing for export are heat-treated lumber with an IPPC stamp. Plywood skin is exempt, which suits art crates well because the sheathing is mostly plywood. Check APHIS and the destination plant-protection authority for the specific rule.

Galleries and museums often send works back. We keep the crate spec on file so a returning work can be repacked in a matching crate, and a reusable crate can be built with screws so it opens and closes many times.

Multiple works and exhibition loans

Exhibition loans arrive as a group, and a registrar wants each work identifiable on the dock. We label the outer crate with a loan number, the inner box with the title and the lid with the opening instructions, and we pack works of similar size into one crate only when partitions keep each in its own padded pocket.

Unframed works on paper travel flat in a portfolio case within the inner box, between rigid boards, with interleaving tissue. Works that are glazed and heavy, such as a large mirror-faced piece, are crated singly. Our crate spec records the order the works come out so the installer can unpack in sequence.