Aluminium or steel scaffolding: weight, cost and service life
Ask ten scaffolders which material is better and you will hear two camps. One side says galvanised steel survives anything; the other says aluminium saves your back and your fuel bill. Both are partly right. The useful question is not which metal is better, but where the difference in weight actually costs you money, and where the extra toughness of steel pays for itself.
What separates the two metals
Steel has a density of roughly 7.85 g/cm³, aluminium about 2.7 g/cm³. On paper aluminium is almost three times lighter. In practice an aluminium component weighs about half as much as its steel equivalent, not a third. The reason is stiffness: under the same load and with the same cross-section, aluminium deflects about three times as much as steel. Manufacturers compensate with thicker walls and different profiles.
The standard scaffold tube shows this well. Both versions have an outside diameter of 48.3 mm (the size defined in EN 39 for steel tube). A steel tube typically has a 3.2 mm wall and weighs around 3.6 kg per metre. The aluminium tube needs a wall of about 4 mm and still comes in at around 1.5 kg per metre.
Corrosion protection differs as well. Steel scaffolding is almost always hot-dip galvanised. The zinc protects the steel even at small scratches, because the zinc corrodes in place of the iron. Aluminium forms a thin oxide film of its own and needs no coating, but it does not like alkaline materials such as wet mortar, fresh concrete or lime, and it can suffer galvanic corrosion when it sits against other metals in damp conditions for months.
Weight per component and per square metre
Exact figures depend on the manufacturer and the version. The values below are indicative and refer to a frame scaffold 0.73 m wide. For your own calculation, use the data from the manufacturer's instructions or our guide on scaffolding weight.
| Component | Steel (approx.) | Aluminium (approx.) |
|---|---|---|
| Vertical frame 2.00 × 0.73 m | 17–20 kg | 8–11 kg |
| Deck 3.07 × 0.32 m | 18–21 kg | 11–14 kg |
| Guard rail 3.07 m | 5–7 kg | 2–3 kg |
| Diagonal brace for a 3.07 m bay | 8–10 kg | 4–5 kg |
| Scaffold tube per metre | approx. 3.6 kg | approx. 1.5 kg |
| Complete scaffold, per m² of facade | approx. 18–22 kg | approx. 10–13 kg |
A single steel frame at just under 20 kg is easy for one person to handle. The weight becomes a problem in the total: when material is passed up lift by lift, loaded by hand and driven to site.
Worked example: a detached house scaffolded on all four sides
Take a two-storey house in Ireland with a footprint of 10 × 8 m and an eaves height of 5.8 m, scaffolded all round for new render and gutters. The perimeter is 36 m; with the corners we allow roughly 38.5 m of scaffold length. The top lift sits about 1 m above the eaves, so the scaffold is around 6.8 m high. That gives about 262 m² of scaffold area (see calculating scaffold area for the method).
- Steel frame scaffold: 262 m² × approx. 20 kg/m² = about 5.2 t
- Aluminium frame scaffold: 262 m² × approx. 11.5 kg/m² = about 3.0 t
The gap of about 2.2 t is moved by hand at least four times: loading, unloading, erecting and striking, often a fifth time into storage. Over one job a two-person team lifts more than 20 t of steel, against roughly 12 t of aluminium. For an experienced crew this is everyday work. For a painter who scaffolds his own jobs with one labourer, it decides how tired the team is by Friday.
Transport: where the difference really counts
Weight decides which vehicle you need. Suppose your van or trailer combination can carry about 1,200 kg of payload. That is enough for roughly 100 m² of aluminium scaffold, but only about 60 m² of steel. For the house above, steel means five trips and aluminium three. Check the towing limit of your vehicle and the driving licence rules in your country before you plan on that basis; our guide on transporting scaffolding covers load securing.
If the material arrives on a lorry with a crane, the weight matters much less. The same applies to overseas buyers: in a 40-ft container, steel scaffolding tends to reach the payload limit before the container is full, while aluminium usually runs out of space first. In both cases the price per m² and the service life move to the front of the decision.
Purchase price, resale and wear
Aluminium is a more expensive raw material and harder to process, so aluminium scaffolding usually costs noticeably more per m² than a comparable steel system. Both hold their value: well-kept material in a widespread system can be resold after a project. Used scaffolding lowers the entry cost, provided it has been properly checked. As an indication (October 2026), a complete used frame scaffolding package runs at around €30 to €40 per square metre, VAT excluded, and big jobs come out cheaper per square metre. The scaffolding calculator gives you a parts list and an indicative price for your own building.
How steel wears
Galvanised steel lasts for decades in normal use. The typical damage is mechanical: frames bent by a vehicle, dented decks, damaged hooks or claws. The zinc layer suffers from hammer blows, from being dragged over concrete and from render being scraped off with sharp tools. Where the zinc has gone, red rust appears. Light surface rust is usually harmless; deep corrosion at welds, claws or tube ends means the part is scrapped.
How aluminium wears
Aluminium does not rust in the usual sense, but it is softer. Dents and crushed sections appear faster, for example when frames are dropped off a truck bed. Hooks on decks wear more through friction. Mortar and concrete residues attack the surface and should be washed off promptly. Well cared for, aluminium also reaches a very long service life.
For both materials: a bent part is taken out of service, never straightened. When buying used, check the zinc at tube ends, claws and welds on steel, and look for dents in the legs, worn hooks and etched surfaces on aluminium. Stamps should be legible so that manufacturer and system can be traced. Our quality check covers exactly these points.
Load capacity and mixed builds
What a scaffold may carry depends on the system and its documentation, not on the metal as such. Many aluminium frame systems are rated for class 3 under EN 12811-1, which means 2.00 kN/m² of distributed load. That covers painting, rendering and insulation. Heavy brickwork and stone with load class 4 or higher usually calls for steel systems with suitable decks. See load classes and width classes for the details.
Mobile towers to EN 1004 are almost always aluminium, because a light tower is easier to move. A light tower also tips more easily, which is why stabilisers and, where the instructions require it, ballast are part of the design.
A common and sensible combination is steel frames with aluminium decks. The frames stay robust, while the decks, which make up a large share of the total weight and are handled most often, get lighter. Some used systems, Layher Blitz for example, exist in both steel and aluminium versions. Whether a mixed build is permitted is decided only by the manufacturer's instructions. Parts not listed there do not belong in the scaffold, even if they seem to fit.
Who should choose what
| Situation | Rather steel | Rather aluminium |
|---|---|---|
| Homeowner, one house, few uses | if delivered by lorry and helpers are available | if you transport it yourself and erect it as a pair |
| Painting contractor, changing sites | with own lorry and crane | with van and trailer |
| Scaffolding contractor, daily use | main fleet | small quick jobs |
| Brickwork and stone | higher load classes | only with matching documentation |
| Interior work, mobile towers | rarely | standard |
Run your own numbers before you decide: scaffold area times 20 kg/m² for steel or about 11.5 kg/m² for aluminium, then work out which vehicle and how many trips you need. If the material is in use every day, has to carry heavy loads or arrives by lorry, steel remains the solid choice. Browse current offers of steel scaffolding and aluminium scaffolding, or send us your dimensions and we will price both options.