System scaffold vs tube and fitting: one 10 m wall, counted both ways

Before you rely on this guide

This guide summarises published rules to help you plan and is not legal advice. It has not been reviewed by a qualified scaffold designer or engineer. ScaFix is a planning aid, not structural approval: the manufacturer's instructions, the scaffold design and a competent person's inspection decide what is built and used on site.

What exactly is being compared?

Both counts describe a tied independent scaffold along a straight 10 m wall, two boarded lifts high, with double guard rails and toe boards on the boarded lifts. They are not identical structures, and the differences matter more than the totals, so here they are side by side before any numbers.

The system scaffold is 0.28 m longer and half a metre taller, so if anything it is the larger structure. Neither count includes a loading bay, a ladder tower or sheeting.

How many pieces does each one need?

Before ties, the tube and fitting scaffold needs 291 loose items: 75 tubes, 34 boards, 152 couplers, 12 end caps, 12 base plates and 6 sole boards. The Layher Allround version needs 152 kit pieces. The engine adds 26 tie items, 12 wall ties, 12 anchor fittings and 2 couplers, for 178 in total.

The engine's full list for the system side is below, exactly as the app computes it.

Parts list: Layher Allround, 10.28 m × 6 m

Fixed example computed by the app’s engine: no corners, openings, sheeting, hoists or loading bays. The manufacturer’s assembly instructions decide; this is planning, not structural approval.

The tube and fitting side of the count

The tube and fitting list, row by row with lengths, is on the worked count page. Its biggest single line is the right-angle coupler, 88 of them, followed by 36 putlog couplers, 20 swivels and 8 sleeves.

Where does the planning effort actually go?

Not into the number of lines. Both lists come out at roughly fifteen rows, because tube and fitting packs everything into a few tube lengths while a system list names each component. The effort sits in the decisions behind each row, and those are very different in kind on the two sides.

On a tube and fitting job the planner decides the transom positions so that no board span exceeds the sheet's 1.2 m, where the board joints fall and which pair of joint transoms carries them, how the ledger runs are made up from 21 ft and 13 ft tubes, where the sleeve couplers go, and which standards take ledger bracing. Every crossing is a coupler someone must choose and later tighten. Change one bay length and half the list moves.

On a system scaffold most of those decisions are already made by the kit. Bay lengths come from the ledger and deck lengths in the catalogue, the lift height from the standard's node spacing, and the connection is fixed by the product: in Layher Allround a wedge head slides over the rosette, its wedge drops into a hole and is hammered home with a metal hammer of at least 500 g, and one rosette takes up to eight components (Layher Allround instructions, edition 04.2018, § 3.2). The planner chooses the system, the bay mix and the lifts; the counts follow.

That is also why a system scaffold can be counted by software from wall dimensions and a tube and fitting scaffold, in practice, cannot without a compliance sheet in front of it.

How is each one designed in the UK?

The legal starting point is the same for both. The Work at Height Regulations 2005 require strength and stability calculations unless a note of calculations for the arrangement is available or the scaffold is built to a generally recognised standard configuration (Schedule 3, paragraph 7). What counts as that configuration differs.

For tube and fitting, it is NASC's TG20:21. HSE notes that TG20:21 gives a range of compliant scaffolds that can be boarded at any number of lifts, but only two platforms can be used as working platforms at any one time (HSE). The output is a compliance sheet for the specific scaffold, the document our worked count borrows its limits from, and NASC publishes an operational guide to go with the eGuide.

For system scaffolds, HSE is explicit: proprietary system scaffolds must be erected and tied according to the manufacturers' instructions, and a system scaffold outside the manufacturer's guidance needs a bespoke design (HSE). So the system planner works from the manufacturer's instructions and tie tables rather than from TG20.

When does tube and fitting still win?

Tube and fitting is straight tubes and universal couplers, so it follows geometry no kit was made for: stepped and irregular facades, bridging over a canopy, scaffolds around plant and pipework, and bay lengths cut to fit between obstructions. Where a system layout needs special pieces at every turn, the system advantage on the parts list can disappear.

The two are also mixed. Layher's own corner details close a projecting bay's side protection with tubes and couplers, and even the engine's Allround list above includes right-angle couplers for the wall ties.

When does system scaffold win?

On repetitive facades: houses, terraces, flats and commercial elevations where the same bay repeats along the wall. The kit fixes bay lengths and lift heights, so the count, the check and the load-out all follow from the layout. Fewer loose parts also means fewer things to forget on the lorry.

The trade-off is that you must own or hire the right components, and a scaffold outside the manufacturer's instructions needs a design.

How do you compare the two on your own job?

Count the same wall twice, with the same boarded lifts and the same rules for ties and access, once from the tube and fitting compliance sheet and once from the system manufacturer's data. Then compare piece counts and couplers, not only the totals, and check what each count leaves out.

1. Take the same wall. Length, height and the lifts that must be boarded, from the drawing or a survey.
2. Count tube and fitting from the compliance sheet. Use our worked method with the limits on your own TG20:21 sheet; our page on the TG20 compliance sheet explains what it fixes.
3. Count the system scaffold from the manufacturer's data. Enter the wall in ScaFix and pick the system you hold: it computes the bays, lifts and parts list from the manufacturer's bay lengths.
4. Compare like with like. Same boarded lifts, ties counted on both sides or on neither, and access and loading bays kept as separate structures.

Before you rely on either count

Both counts illustrate a method; neither is a design. In Great Britain the Work at Height Regulations 2005, enforced by HSE, apply: tube and fitting follows the TG20:21 compliance sheet for the actual scaffold, a system scaffold follows its manufacturer's instructions, and a competent person inspects it before use.

Frequently asked questions

Sources

Primary sources used for this article, with the date each was read.

• HSE: Scaffolding (system scaffolds to the manufacturer's instructions, TG20:21, scaffolds that need a design) (read 25 October 2026)
• Layher Allround Scaffolding, Instructions for Assembly and Use, edition 04.2018, § 3.2 wedge connection (pdf) (read 25 October 2026)
• legislation.gov.uk: Work at Height Regulations 2005, Schedule 3 (strength and stability calculations) (read 25 October 2026)
• TG20:21 compliance sheet, tied independent tube and fitting scaffold (planning application, 1 February 2025) (read 23 October 2026)
• NASC: TG20:21 Operational Guide (read 23 October 2026)