Climbing hold materials compared: polyurethane, ABS, fibreglass and wood.

Climbing hold materials comparison table

The right material is mostly decided by the size of the feature. The table below compares the five materials found on climbing walls across the properties that matter to gyms and route setters.

Polyurethane (PU): the standard for everyday holds

Polyurethane is the default material for small and medium climbing holds because it is tough, rigid at hold scale and can be cast into almost any shape. PU holds are generally made by pouring liquid resin into a mould, so a single mould can produce the same shape repeatedly in any colour. Rockcity supplies PU holds across all categories — jugs, edges, crimps, slopers, pinches and pockets — in its competition colour palette of around 20 colours.

Because PU holds are solid, their weight rises quickly as they get bigger, which is why very large features are usually made as hollow shells instead. Commercial PU holds typically last 5–10 years in a busy gym with regular cleaning. The main failure modes are texture wear, bolt-hole cracking from overtightening and T-nut failure. Standard holds are tightened to 20–25 Nm on M10 stainless bolts, staying near 20 Nm on thin-walled crimps and small edges where there is less material around the bolt hole.

VTF ABS: rigid macros at half the weight of fibreglass

VTF ABS gives large macros a practical balance of stiffness, weight and impact resistance. VTF stands for Vacuum Thermo-Formed: a sheet of ABS (Acrylonitrile Butadiene Styrene) thermoplastic is heated and drawn over a mould by vacuum pressure to form a rigid, thin-walled shell. The result is as rigid as fibreglass under climbing load, approximately half the weight, and far less brittle.

The weight saving changes how resets work. Large macros that would have needed three people to handle in fibreglass can typically be reset by two, and VTF ABS absorbs drops and knocks during crating and storage that would chip or crack GRP. Rockcity makes its VTF ABS macros in-house in Hull using a flangeless design — most thermoformed macros keep a visible lip around the edge, which Rockcity removed after three years of R&D with aerospace and mechanical engineers. The method is Patent Pending WO2025/191268.

On VTF ABS, texture is applied as a coating, so care should protect that finish. Rockcity's guidance is that VTF ABS macros last longer than PU holds, and ABS is easier to recycle at end of life than fibreglass. Fix large macros on 21 mm or thicker birch ply, tightening M10 stainless bolts progressively in a cross pattern to 20–22 Nm.

Fibreglass (GRP): stiff, but heavy and brittle

Fibreglass, or glass-reinforced plastic (GRP), is very stiff but becomes heavy and brittle as macros get larger. GRP features are generally built by laying glass fibre and resin into a mould, producing a hard shell that holds thin, precise edge profiles well — the reason it was long used for competition macros.

The drawbacks show up in day-to-day handling. A large fibreglass macro can crack when dropped or knocked during a reset, and edges chip when pieces knock together in crates. For gyms resetting every week, that means more careful handling, more people per lift and a higher replacement rate. Rockcity ceased all GRP macro production in 2025 and moved its macro range entirely to VTF ABS. Existing GRP macros can still be used, but they should be handled and stored with care and inspected for cracks before every installation.

Plywood and wood: volumes and training holds

Plywood is the material for volumes, the large structural shapes that change the angle and terrain of a wall rather than acting as a single grip. Rockcity makes its plywood volumes in-house in Hull from birch plywood, in full-textured finishes (painted to order in twelve colours), Iconic dual-texture finishes and Safari Print finishes in Leopard, Tiger and Zebra.

Plywood volumes are rigid and robust, but only when they are fixed properly: use every fixing point the volume was designed for, typically four or more, with the same M10 bolt standard as holds. Keep volumes dry in storage and check that the T-nuts behind them are sound before installation, because a fixed volume hides the panel surface.

Solid wooden holds are a different product. They are usually shaped from hardwood rather than cast, have a smooth, untextured surface, and are widely used on fingerboards, campus rungs and home training walls because they are gentle on skin over repeated sessions. The lower friction makes small wooden shapes harder to use, so they are less common on commercial setting walls. Wood should be brushed dry rather than soaked.

Single texture vs dual texture

Texture is a setting choice that applies across PU, VTF ABS and plywood. A single-texture (full-texture) hold has the same grippy finish over its whole surface, so any part of it can be used. A dual-texture hold has a coarser grit on the intended contact zones and a smoother finish elsewhere. Dual texture is a route-setting tool, not decoration: it shows climbers which part of the feature to use without relying on hold orientation alone.

Dual texture suits intermediate to competition circuits, where setters want to restrict foot smears or enforce specific hand positions. Single texture remains the better fit for introductory circuits, where comfort and approachable grip matter more than precision. Dual-texture zones collect chalk faster than smooth areas, so they benefit from targeted brushing between full washes.

Care by material

The same cleaning method works for PU holds and VTF ABS macros: brush dry first, wash with citric acid powder dissolved in warm water (a few percent solution), scrub with a medium nylon-bristle brush, rinse thoroughly and let everything dry completely before reinstalling. Citric acid dissolves chalk without stripping texture or leaving a residue.

Never use wire brushes, abrasive pads, pressure washers, bleach or solvent-based cleaners on any textured hold. Dishwashers are too hot for most PU holds and can warp thinner shapes. Store small holds in foam-lined crates, and store macros face-up or face-to-face with protective material between them, without heavy items stacked on top.