How a museum case is built, what is allowed to touch a paint surface, why a canvas travels upright on its edge, and what humidity does inside a lorry.
Art crating is the part of a picture move that decides everything else. A painting that travels in a properly built case, standing upright on its edge, with the glazing taped and a sheet of glassine between the surface and anything else, arrives in the condition it left. The same painting laid flat under a stack of blankets can arrive with a split corner, a bloomed varnish or a dented canvas. This page is about the workshop craft rather than the logistics: how a museum crate for a painting is put together, what may touch a paint surface and what may not, and what temperature and humidity do inside a vehicle.
The crating and packing described here is what our white-glove crew does on art jobs, and what the specialist carriers we sub to on the highest-value pieces do as well. If you want the wider picture first — what counts as fine art, valuation and insurance limits, survey lead times and the storage question — the companion article on safely moving fine art and valuable collectibles covers that ground. What follows is the detail underneath it.
A proper art case is a box inside a box. The outer shell is birch or poplar plywood, usually 12mm for cases under about a metre and 18mm above that, screwed to internal softwood cleats at every edge. Screws, never nails: hammering a nail sends a shock straight through the case, and a nailed lid cannot be taken off and put back on without splitting the ply. The lid closes onto a strip of closed-cell neoprene so the case actually seals, and the lid screws bite into threaded inserts rather than raw plywood, so the case survives being opened and closed a dozen times over its life.
Inside there are two cushioning layers doing two different jobs. The outer layer is dense polyethylene plank foam, typically 25–50mm thick, cut so the inner tray floats clear of every wall, corner and the base. That layer absorbs impact. The inner layer is a softer polyethylene sheet or Ethafoam that touches the wrapped work and spreads the pressure evenly across the frame. Foam density is a real decision, not a detail: foam that is too soft bottoms out under the weight of a heavy frame and the shock goes straight through, foam that is too hard transmits vibration instead of damping it.
The case also has to buffer moisture, which is why the inside is lined with a foil-faced barrier film or the wrapped work is sealed inside its own polythene envelope before it goes into the foam. A sealed, foam-lined case holds its own internal humidity for several days regardless of what the weather is doing outside it. That single property is the reason we crate for long journeys even when a pad-wrap would survive a twenty-minute run across town.
Two practical points people forget. First, battens on the base: a case with runners underneath can be lifted by a pallet truck and never sits flat on a wet tail-lift or a dusty floor. Second, the timber. Any wooden case crossing a border has to be ISPM 15 heat-treated and stamped, or it gets refused at the port, so the cases we build for international removals are made from certified stock from the outset. Expect a finished case to roughly double the weight of the piece inside it, which changes the crew size and sometimes the access plan. Cases are built to measurement through our custom crate service, and the export-grade versions through export packing and crating.
An unframed canvas on a stretcher is the most vulnerable thing in the house, because there is nothing standing proud of the paint surface. The answer is a travel frame: a plain timber strainer built slightly larger than the stretcher and fixed to the stretcher bars from the reverse, never through the canvas. It gives the crew something to hold, it keeps every wrapping layer clear of the paint, and it means the work can be set down on its edge without the surface touching anything. For a large contemporary canvas this is the single most useful hour of preparation there is.
Framed works under glass need the glazing dealt with before anything is wrapped. We tape the glass in a lattice with low-tack filament or masking tape, corner to corner and then in bands across. The tape does not stop the glass breaking; it stops broken glass sliding across the surface of the work if it does. Tape goes onto the glass and stops short of the rebate, because it must never be pressed onto gilding or a painted frame surface, where lifting it takes the finish with it.
For anything valuable, the better answer is to swap the glass for acrylic before the move and put the glass back afterwards. Acrylic weighs less, does not shatter, and removes the risk entirely. There is one firm exception: acrylic carries a static charge and will lift pastel, charcoal, chalk and any unfixed friable medium straight off the paper. Those works keep their glass, get taped, and travel flat in a purpose-built shallow case with support under the whole sheet.
Two more things go on the back. A backing board of acid-free board or Correx, screwed into the frame rebate, stops a knuckle or a strap pushing through the canvas from behind and noticeably damps vibration in transit. And the hanging hardware comes off or gets taped down: a loose D-ring, mirror plate or length of picture cord swinging free is the most common cause of a scratch on the next painting in the rack. Corner protectors then grip the frame itself, never the artwork.
The layer against the artwork is chosen first and everything else is built outwards from it. For a paint surface or a varnished panel that layer is glassine: a smooth, semi-translucent, low-permeability paper that will not emboss, will not shed fibres and will not stick to a soft varnish on a warm day. Glassine is a transit material rather than a long-term archival one, which is exactly what a move needs.
For works on paper, textiles and photographs the layer is acid-free tissue, and the choice between buffered and unbuffered matters. Buffered tissue carries an alkaline reserve that protects wood-pulp paper from its own acidity. That same alkaline reserve is wrong against protein-based materials — silk, wool, vellum — and against most photographic emulsions, which want unbuffered tissue. Getting this backwards does no harm in a week of transit, but the wrapping often stays on for months in storage, and then it does.
Bubble wrap never touches a surface. Under the weight of a frame, and particularly in a warm vehicle, the bubbles emboss a regular pattern into varnish, gesso and photographic emulsion, and the polyethylene traps moisture against the finish. Bubble wrap has a place, but it goes outside a glassine or tissue layer and it goes bubbles facing outwards. The same rule applies to any plastic sheet against a gilded frame: water gilding lifts under pressure and friction, and it does not go back.
Handling follows the same logic. Nitrile gloves for painted and varnished surfaces, cotton for metal, silver and photographs where fingerprints etch. A frame is carried by its two vertical sides, never by the top rail, and never by the hanging wire. Tape only ever bonds to itself or to an outer wrap, never to the object. These are the same instincts our crews use on antique furniture and veneers, and the same reason the antiques moving service and the art work sit with the same people.
A stretched canvas is a drum. Laid flat, it flexes with every bump in the road, and the paint layer on top of it is far more brittle than the fabric underneath. That mismatch is what produces cracking, cupping and eventually flaking. Stood on its edge, the load runs down through the stretcher bars and the frame, which are the parts built to carry it, and the canvas barely moves at all. The second reason is less technical and just as important: anything that shifts in the back of a lorry lands on a flat painting and misses an upright one.
In the vehicle, paintings stand face to face and back to back, so that glass meets glass and frame meets frame rather than frame meets canvas. They go into slotted racks with padded dividers, or they are strapped against a padded bulkhead. They never lean on a bare side wall: the side wall is where vibration is worst and where condensation forms first when a cold morning meets a warm load. Foam feet or a padded batten go under the bottom edge so the frame is not resting on a hard deck, and straps run over padding and are tensioned by hand rather than ratcheted down.
Loading order is part of the method. Art goes on last and comes off first, which keeps it near the tail-lift, out from under everything else, and out of the vehicle in the shortest possible time. On a mixed household job the art travels in a section of the load separated by a bulkhead of pad-wrapped furniture, using the same pad-wrap method we use on everything else.
There are exceptions to the upright rule and they are worth knowing. Unframed works on paper, pastels, very large thin panels and anything with a lifting or flaking paint layer travel flat, in a shallow purpose-built case with continuous support under the entire surface. Flat is safe when the support is total; flat is dangerous when the work is spanning a gap. That distinction is what the survey is deciding when we look at each piece.
The back of a vehicle is the harshest environment anything owns. A box body standing in July sun climbs well above the outside air temperature within an hour, and the same body at five in the morning in February sits below it with damp air inside. Art responds to both. Canvas takes up moisture and slackens when it is damp, then tightens as it dries, and a canvas tightening over a cold night pulls on a paint layer that cannot stretch with it. Panel paintings and veneered frames move across the grain and cup or split. Varnish blooms into a milky haze when warm, moist air meets a cold surface.
What matters is the rate of change rather than the absolute number. Art that has lived in a draughty Sussex farmhouse for fifty years is acclimatised to that house, and a slow drift of a few degrees does nothing at all. A twenty-degree swing in ninety minutes is what causes damage. This is why the crate matters more than the vehicle for most jobs: a sealed, foam-lined case with a vapour barrier flattens the curve and holds its internal conditions for days, so the artwork never experiences the swing the lorry does.
Our own lorries are insulated but they are not climate-controlled, and we say so plainly. For household art that is generally fine inside a proper case. Above roughly £25,000 a piece, or for anything a conservator has already flagged as unstable, we sub the transport to a specialist art carrier whose vehicles hold and log temperature and humidity for the whole journey. On longer runs we put a small data logger inside the case, so if there is ever an argument about conditions there is a record rather than an opinion.
The most common mistake happens at the destination, not on the road. Never open a cold crate in a warm room. Condensation forms on the coldest surface in the room, which will be the glass or the paint you have just brought in from a lorry. Leave the case closed, in the room it will live in, for at least twenty-four hours so its contents reach room temperature, and only then unscrew the lid. If the move includes a gap between completion dates, the same logic applies to storage: our Lower Dicker storage depot is insulated and stable enough for crated household art, and for collections needing regulated humidity we place them with specialist art-storage providers instead.
A condition report is a written and photographed record of the state of a piece before it is packed, repeated on arrival by the same person in the same order. It is the least glamorous part of an art move and the part that settles every disagreement that ever arises. Without one, a chip that has been there since 1974 becomes a conversation nobody enjoys having.
The photography is done in two passes. First a square-on overall shot with even light, at the highest resolution the camera manages. Then raking light: a single lamp held almost parallel to the surface, sweeping across it. Raking light is the whole trick, because it throws shadow into every irregularity and shows craquelure, cupping, tenting, planar distortion, old fills and previous restoration that are invisible when you look at the picture face-on. Then close-ups of all four corners, the signature, any existing loss, and the entire reverse — the back of a painting carries labels, stencils and exhibition stamps that are part of its provenance and are worth photographing before they get covered up.
The written half uses shared vocabulary so both parties mean the same thing. Craquelure is the fine network of age cracks in a paint or varnish layer. Cupping is where those islands of paint curl at their edges. Tenting is a raised ridge of paint about to detach, and it is the one that means stop and call a conservator. Abrasion is surface wear, foxing is the brown spotting on paper, bloom is the milky haze in varnish, planar distortion is a warped panel or a slack canvas, and accretion is anything sitting on the surface that should not be. Each observation gets a location, marked on a printed copy of the overall photograph.
Both sides sign and date the report and both keep a copy, including the photographs. Budget ten to fifteen minutes a significant piece: a collection of thirty works is most of a working day and needs to be in the schedule rather than squeezed into move morning. The same file is what an insurer asks for if a claim is ever made, so it sits alongside the valuations and the goods-in-transit cover and declared-value limits rather than replacing them.
We are a family-run Sussex remover. Crews are directly employed and trained at our own staff training centre, which is why the same people who build a case are the people who load it. Pad-wrap on every full removal, removal-grade cartons, BAR Advance Payment Guarantee on every deposit.
120+ independent Google reviews at 4.9/5. Survey, written quote within 48 hours, deposit-protected booking, calm move day. Whichever category your move falls into — routine local, overseas, antiques, business — the approach is the same.
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Bespoke cases are built to a measurement, so the measurement has to happen early. At survey we record height, width and depth over the frame at its widest point, including any decorative moulding that stands proud, plus the weight and the glazing type. The case is then drawn with the foam thickness added on every face, which is why a modest picture ends up in a case a good deal larger than people expect. Get the dimensions wrong by a centimetre and the piece either rattles or has to be forced, and both are worse than no case at all.
Build time is the reason art jobs need longer lead times than ordinary removals. Allow one to two weeks for a small run of cases and longer for a whole collection, on top of the usual booking window. For end-of-month dates in the May to September peak we ask for ten to fourteen weeks’ notice on art work, and sixteen weeks or more where a specialist carrier or an insurer’s sign-off is involved. If the date is already fixed and tight, say so at the first phone call; there are usually reusable slot cases and travel frames that can carry the job without a bespoke build.
De-crating at the other end has its own sequence. The case comes into the room it will live in, stays shut for its acclimatisation period, and is then opened lid-up on trestles rather than tipped onto its face. The wrapping comes off in the reverse order it went on, glassine last, with the condition report in hand so the arrival check happens while the crew is still there. Hanging is a separate conversation: the wall fixings, the height, and whether the wall itself can carry the weight.
What happens to the cases afterwards is worth deciding in advance. One-trip cases are broken down and taken away for recycling. Reusable cases can go back to our depot for storage against a future move, or stay with you if the collection travels regularly to exhibitions. Either way we would rather agree it at survey than leave four large plywood boxes standing in a new hallway on completion day.
One last piece of aftercare that costs nothing. Once the work is hung, keep it off external walls where humidity varies most, out of direct sun, and away from the wall directly above a radiator, where the heating cycle drives the local humidity up and down twice a day. Those three choices do more for a painting over a decade than anything that happens in a single move day.
Booking your move with us is a five-step process. One: enquire via the online quote form or call our office on 01323 848 008. We’ll arrange a survey within a few working days. Two: the survey itself, usually in-home and lasting 30–90 minutes depending on the move complexity, and longer where there are pictures to measure for cases. The surveyor walks the property, photographs access points, counts cartons by size, records frame dimensions and glazing, and discusses any specialist requirements.
Three: the written quote, emailed within 48 hours of the survey. Itemised by line so you see what every cost line covers. Four: deposit and date confirmation. Typically 25% deposit on confirmation, fully protected under the British Association of Removers’ Advance Payment Guarantee. Five: the move itself. Uniformed crew, our own lorry, no agency labour, blankets washed between jobs.
For pre-move questions, our office is reachable Monday to Friday 8am to 5:30pm and Saturday 9am to 1pm. We’d rather have the customer conversation early than late — a small clarification three weeks before move day saves a meaningful misunderstanding on the day itself. For the wider company background and our BAR membership, BS 8564 accreditation and FHIO registration, the about-us page covers it.
For your specific move, we look forward to the conversation. Whether it is one painting that needs a case and a careful drive or a whole collection with condition reports and a specialist carrier, the principles are consistent: survey and measure, written itemised quote, deposit-protected booking, crated and reported both ends, calm move day. That’s the standard we aim for on every job, and it is what the 120+ reviews behind our 4.9 out of 5 rating are describing.
A travel frame is a plain timber strainer fixed to the back of an unframed canvas so nothing can touch the paint and the crew has something safe to hold. A crate is the outer plywood case with foam inside it. A big canvas often needs both: the travel frame protects the surface, the case protects the whole assembly.
Taping the glass in a lattice is the quick answer and it works — the tape holds the shards if the glass breaks so they cannot sweep across the surface. Swapping to acrylic before the move is better for anything valuable. The exception is pastel, charcoal or chalk: acrylic carries a static charge that lifts loose media off the paper, so those works keep their glass.
No. Under the weight of a frame in a warm vehicle the bubbles emboss a pattern into varnish, gesso and photographic emulsion, and the plastic traps moisture against the finish. Glassine or acid-free tissue goes against the work first; bubble wrap sits outside that layer with the bubbles facing outwards.
At least twenty-four hours in the room where the work will hang. Opening a cold case in a warm room condenses moisture onto the coldest surface in the room, which will be the glass or the paint. Letting the sealed case come up to room temperature first avoids that entirely.
That is raking light, and it is how a condition report finds things. A light almost parallel to the surface throws shadow into every irregularity, showing craquelure, cupping, tenting, warping and old restoration that are invisible in flat light. We do it before packing and again on arrival so any change is obvious.
Allow one to two weeks for a small run of cases once the measurements are taken, and longer for a full collection. That sits on top of the normal booking window, which is why we ask for ten to fourteen weeks’ notice on art work and sixteen or more where a specialist carrier or an insurer’s approval is involved.