Summer in the UAE reaches 45°C in the shade. A dark sign face in direct sun gets much hotter than that. So the question we hear from signage buyers is fair: will acrylic last outdoors here? The answer is yes, if you use the right grade and fix it the right way. This guide covers what works, what fails, and what to ask for.
Material guides · 2026-09-15 · 6 min read
Good quality acrylic is naturally UV stable. Unlike polycarbonate, which yellows unless it has a coating, cast acrylic keeps its clarity for years in direct sun. This is why aircraft windows and outdoor aquariums use it. The key phrase is 'good quality'. Cheap sheet from an unknown mill may not have the same UV stabilisers. Ask what sheet brand is being used.
Acrylic softens around 90 to 100°C. A sign will not reach that in the UAE. But a black acrylic face in July sun can pass 70°C, and the sheet expands as it heats. A one-metre sign can grow by 2 to 3mm between a January night and a July afternoon. If the sign is screwed tight with no room to move, it cracks at the screw holes. This is the number one outdoor failure we see.
Extruded acrylic is cheaper and fine for indoor displays. Outdoors, it is more likely to craze and crack under heat cycling. Cast acrylic has better heat resistance, better resistance to cleaning agents, and stays flatter. For outdoor signs, letters and light box faces we cut cast sheet as standard.
Indoors, 3mm letters are fine. Outdoors, go 5mm minimum for letters and 8 to 10mm for anything over 300mm tall. Thicker sheet warps less and survives wind load. On colour: dark solid colours absorb the most heat. If you can, use a light face with dark print, or a lit sign with an opal face, which runs cooler.
Oversize the holes so the screw can move as the sheet expands. Use a washer with a soft gasket. Never tighten to the point where the acrylic is compressed. For large panels, use a channel or a frame that holds the edges but lets them slide. For 3D letters, stud mounting with a small stand-off keeps air moving behind the letter and lets it expand freely.
UAE dust and coastal salt scratch the surface over time. Acrylic can be polished back, unlike coated polycarbonate, which cannot. Clean with water and a soft cloth, not a dry rag and never solvent. If a sign faces a sandy car park, ask for a slightly thicker sheet so it can take a polish in a few years.
Cast acrylic, 5mm or more, light colours where possible, oversize fixing holes, a gasket under every screw, and a frame that allows movement. We send a drawing showing the fixing points, so the installer does it the same way. Done like that, an outdoor acrylic sign in the UAE lasts 7 to 10 years before it needs refreshing.
Acrylic survives the UAE sun well. What kills it is heat expansion against tight fixings, and cheap extruded sheet. Specify cast, 5mm plus, and give it room to move.
Questions about your own project? Talk to our Dubai workshop, we answer the same working day.
Good quality cast acrylic does not yellow for many years. Polycarbonate without a UV coating does. Ask for the sheet brand so you know the UV stabilisers are real.
No. Acrylic softens above 90°C and a sign face rarely passes 70°C even in July. The risk is expansion cracking at tight screw holes, not melting.
5mm minimum for small letters, 8 to 10mm for letters over 300mm tall. Thicker sheet warps less and resists wind.
Aluminium composite is cheaper for flat printed panels. Acrylic wins for lit signs, 3D letters, and anything that needs depth or a polished edge. Many outdoor signs use both: an aluminium backing with acrylic letters.
Pick your products, add a note, and our team replies the same working day.