Working at Height: Scaffolding, MEWPs and Harnesses
Falls from height are the leading cause of death on construction sites in the UK — dozens of fatalities every year, and thousands of serious injuries. On a self-build, you will inevitably work at height: rendering a facade, fitting a roof structure, laying roof coverings, hanging gutters, applying external insulation… Without the right equipment, a fall from just 3 metres can cause irreversible injuries. This article covers the three solutions for safe work at height — scaffolding, MEWPs and harnesses — and helps you choose the right one for your situation.
When must you protect against falls
The regulations are clear: from 2 metres of potential fall height, you must put protection in place. In practice, on a house self-build, you are working at height as soon as you:
- Climb onto a wall being built up (from the 4th course of blocks upwards)
- Install the roof structure or roof covering
- Apply external render or carry out external wall work
- Fit gutters or first-floor windows and doors
- Work on the roof (aerial, ventilation, waterproofing)
The hierarchy of protection
The fundamental principle: collective protection always takes priority over personal protection. In practice:
- Eliminate the risk: can the work be done from ground level? (telescopic pole, etc.)
- Collective protection: scaffolding with guardrails, safety nets, temporary guardrails
- Personal protection: fall arrest harness — last resort only
Warning — A ladder is never a work platform. It is only for accessing a higher level. Working from a ladder (rendering, drilling, screwing) is the number-one cause of accidents among self-builders.
Scaffolding: the reference solution
Scaffolding is the safest and most comfortable protection for working at height. It provides a stable platform, guardrails and easy access for materials.
Types of scaffolding
| Type | Max height | Use | Hire cost |
|---|---|---|---|
| Aluminium rolling tower | 6–8 m | Occasional work, indoor/outdoor | £80–150/week |
| Fixed facade scaffold (system scaffold) | 20+ m | Rendering, insulation, roofing | £150–400/week |
| Tube and fitting / frame scaffold | 10–12 m | Structural work, wall raising | £100–250/week |

Rolling tower or fixed scaffold: how to choose
Scaffold erection rules
A poorly erected scaffold is more dangerous than no scaffold at all. Here are the non-negotiable rules:
Stability and anchoring:
- The ground must be flat, firm and stable. On soft ground, use base plates under the standards
- Adjustable base plates compensate for uneven ground (max 20 cm of level difference)
- A fixed facade scaffold must be tied to the building every 4 m vertically and 6 m horizontally
- For a rolling tower: lock the castors with the brakes before climbing
Decks and guardrails:
- Each working level must have a complete deck (no gaps, no missing boards)
- Guardrails are mandatory: top rail at 1 m, mid-rail at 45 cm, toe board at 15 cm
- Trapdoors must be closed after use
Access:
- Use the internal ladder bays of the scaffold, never climb up the outside of the structure
- Never climb on guardrails or diagonal braces
Tip — If you hire a facade scaffold, ask the hire company for an erection briefing (often included free with the hire). A correct erection takes 2 to 3 hours for a typical house facade — re-erecting after a collapse takes much longer, not counting the injuries.
Permissible loads
Do not overload the decks — this is a frequent mistake on self-builds when materials are stored on the scaffold.
| Class | Max load/m² | Use |
|---|---|---|
| Class 2 | 150 kg/m² | Painting, cleaning |
| Class 3 | 200 kg/m² | Masonry, render — the standard site class |
| Class 4 | 300 kg/m² | Heavy masonry (stone) |
| Class 5 | 450 kg/m² | Concrete formwork |
Warning — One 25 kg bag of render + a 20 kg bucket of mortar + your weight (80 kg) + a helper (80 kg) = 205 kg on a single deck. With a Class 2 scaffold, you are already overloaded. Always check your scaffold’s load class before bringing materials up.
The MEWP: for occasional access
A Mobile Elevating Work Platform (MEWP) — also known as a cherry picker — is ideal for occasional tasks at height: fitting gutters, roof inspection, tree surgery near the house.
Types of MEWPs
| Type | Height | Advantage | Disadvantage |
|---|---|---|---|
| Scissor lift | 6–12 m | Wide, stable platform | Vertical travel only |
| Articulated boom | 12–20 m | Access over obstacles | More complex, more expensive |
| Telescopic boom | 15–40 m | Long outreach | Less stable, more expensive |
Hiring a MEWP as a private individual
Good news: you can hire a MEWP as a private person. Key points to know:
- Cost: £150–400/day depending on type and height
- IPAF licence: not legally required for a private individual on their own site, but a familiarisation session is strongly recommended (often included by the hire company)
- Ground: the MEWP needs firm, level ground. On soft ground, use outrigger pads or mats
- Access: check that the machine can reach the work area (gateway width, slope, overhead obstructions)
Tip — For fitting gutters on a single-storey house (6–7 m height), hiring a scissor lift for 1 to 2 days is often cheaper than a week’s scaffold hire — and the work goes 3 times faster.
Safety on a MEWP
Even though the MEWP has guardrails, you must wear a harness clipped to the anchor point inside the platform. In the event of a collision or sudden movement, the harness prevents ejection.
- Fall arrest harness (EN 361) + short lanyard (EN 354) clipped to the basket anchor point
- Never stand on the MEWP guardrails
- Never use the MEWP as a crane (no lifting of heavy loads)
- Check the basket’s maximum rated load (operator + tools + materials)
The fall arrest harness: last resort
A harness is a personal protection — it does not prevent a fall, it limits the fall via an energy-absorbing system. Use it when neither scaffolding nor a MEWP is practicable: pitched roof work, roof structure, occasional access at height.
Components of a complete fall arrest system
A harness alone is useless. You need a complete system:
| Component | Standard | Role | Cost |
|---|---|---|---|
| Full body harness | EN 361 | Holds the body during a fall | £50–150 |
| Energy-absorbing lanyard | EN 355 | Limits shock force to 6 kN max | £40–80 |
| Anchor point | EN 795 | Rated at minimum 10 kN | £20–50 (single anchor) |
| Connector (karabiner) | EN 362 | Links the components | £15–30 |
Total system cost: £125–310 — less than a night in hospital.
Correct use of the harness
The harness is the most misused PPE on construction sites. Common mistakes:
-
Lanyard too long: the total fall distance (lanyard + deployed absorber + user height) must not allow contact with the ground or an obstacle. Calculation: 1.5 m lanyard + 1.75 m absorber + 1.80 m height = minimum 5.05 m of clearance below the anchor point.
-
Unsuitable anchor point: a gutter hook, a downpipe or a barge board are NOT anchor points. Use a structural anchor fixed to the roof structure (ridge purlin, wall plate) or a deadweight anchor on the roof.
-
Harness incorrectly adjusted: straps must be tightened snugly. A loose harness causes serious injury during fall arrest (organ compression, pelvic trauma).
Warning — After a fall arrested by the harness, rescue must arrive within 15 minutes. Beyond that, suspension syndrome (compression of veins by the straps) can cause cardiac arrest. Never work alone while wearing a harness — there must always be someone on the ground able to call the emergency services and lower you down.

Roof work: the most common scenario
On a self-build, the harness is used mainly for roofing work. The recommended procedure:
- Install the anchor points from the scaffold (safety hook on the ridge purlin)
- Access the roof via the scaffold (never via a ladder leaning against the roof)
- Clip on immediately to the anchor point as soon as you step onto the roof
- Use an adjustable lanyard to define your working zone without too much slack
- Always work in pairs minimum: one on the roof, one on the ground as spotter
Best practice — Combine protections: scaffold at the base of the wall (collective protection) + harness on the roof (personal protection). The scaffold provides safe access, a materials storage area, and a fall-arrest buffer for any slip on the lower sections of the roof.
Temporary guardrails: passive protection
Temporary guardrails are lightweight collective protections to be installed at floor edges, stairwell openings and flat roof perimeters.
Where to install them
- Floor edges at upper storey level: as soon as the floor slab is cast and before the walls are built up
- Stairwell openings: from the slab pour until the permanent staircase is fitted
- Flat roofs: around the perimeter during waterproofing works
- Balconies: before the permanent balustrade is installed
Regulatory requirements
- Top rail: 1 m above the floor level
- Mid-rail: 45 cm
- Toe board: 15 cm (prevents tools sliding off the edge)
- Strength: must withstand a force of 30 daN (approximately 30 kg) applied horizontally
Tip — Clamp-on posts (Dahl type or equivalent) fix without drilling onto the edges of concrete slabs. Hire cost: £5–10/month per unit. This is the fastest option to install and the most cost-effective for protecting floor edges throughout the second-fix phase.
Cost and usage comparison
| Criterion | Rolling tower | Fixed scaffold | MEWP | Harness |
|---|---|---|---|---|
| Height | Up to 8 m | Up to 20+ m | 6 to 40 m | Unlimited |
| Working comfort | ★★★★☆ | ★★★★★ | ★★★☆☆ | ★★☆☆☆ |
| Safety | ★★★★★ | ★★★★★ | ★★★★☆ | ★★★☆☆ |
| Mobility | ★★★★★ | ★☆☆☆☆ | ★★★★☆ | ★★★★★ |
| Budget (1 week) | £80–150 | £150–400 | £700–2,000 | £125–310 (purchase) |
| Training required | Basic | Recommended | Recommended | Essential |
| Solo work possible | Yes | Yes | Not recommended | No |
Fatal mistakes to avoid
-
Using a ladder as a work platform — A ladder is a means of access, not a workstation. Rendering a facade from a ladder means leaning out, shifting your centre of gravity outside the base of support.
-
Working alone on a roof with a harness — If you fall and the harness arrests you, you are hanging in mid-air. Without someone to call the emergency services, suspension syndrome will kill you within 15 to 30 minutes.
-
Not securing a rolling scaffold tower — A 60 km/h gust is enough to topple an unsecured rolling tower. Lock the castors AND use outrigger stabilisers.
-
Storing heavy materials on a single deck — 20 bags of render at 25 kg each on the same deck = 500 kg. Spread the load across multiple levels.
-
Improvising an anchor point for the harness — A PVC pipe, a barge board or a gutter bracket are NOT anchor points. You need a structural anchor rated to minimum 10 kN.
Where to hire working at height equipment
| Company | Scaffolding | MEWP | Advantage |
|---|---|---|---|
| Loxam | ✅ | ✅ | National network, wide range |
| Kiloutou | ✅ | ✅ | Many branches, online pricing |
| Point.P Location | ✅ | — | Combined with materials purchase |
| Tracktor | ✅ | ✅ | Online comparator, competitive prices |
| Local builders merchant | ✅ | — | Local, delivery possible |
Best practice — Plan your work at height to consolidate hire periods. Rendering + gutters + first-floor windows in the same scaffold hire week = one hire booking instead of three.
Links to related articles
Working at height safety is part of a wider picture. See also:
- Essential PPE on a construction site — helmets, safety footwear and harnesses covered in detail
- Site organisation (storage, flow and signage) — to plan scaffold erection zones
- Construction waste management — to keep circulation routes clear at the base of scaffolding
Checklist: working at height safely
- Identify all work-at-height phases on the project
- Choose the right equipment for the height and duration (scaffold, MEWP, harness)
- Check ground bearing capacity and levelness under scaffold/MEWP
- Erect the scaffold following the supplier’s instructions (guardrails, complete decks, ties)
- Lock castors and fit outrigger stabilisers (rolling tower)
- Check permissible load class before bringing materials up
- Wear EN 361 harness in the MEWP basket and on the roof
- Install structural anchor points (EN 795) before stepping onto the roof
- Calculate the minimum clearance below the anchor point (lanyard + absorber + height)
- Never work alone with a harness — always have a ground spotter
- Fit temporary guardrails at floor edges and stairwell openings
- Group work-at-height tasks to optimise hire costs
- Check self-build site insurance (coverage for work at height + volunteers)
- Brief any helpers on height safety rules BEFORE starting work