Facade scaffold or mobile tower: which one for your job?
A mobile tower goes up in an hour and rolls wherever you push it. A facade scaffold takes a day or more to erect and has to be tied to the building. For a single window that sounds like an easy choice. Along a 30 m elevation with flower beds, light wells and patio steps, the picture changes quickly. Here is how the two compare on site.
Two principles: tied or freestanding
A facade scaffold stands on base jacks close to the wall and is tied into the building at set intervals, as the system's tie pattern specifies. It runs along the wall in continuous lifts, usually 2 m apart vertically. Every point of the facade can be reached without moving anything. Several trades can work on different lifts at once.
A mobile tower is a freestanding tower on four castors. It gets its stability not from ties but from its base dimensions, from stabilisers or outriggers and, depending on the instructions, from ballast. Work happens on a single platform with guard rails. When one section is done, the tower is moved.
Mobile towers are covered by EN 1004. The standard applies to platform heights of up to 12 m indoors and up to 8 m outdoors. What a particular configuration allows is set out in the manufacturer's instructions. Facade scaffolds made of prefabricated components fall under EN 12810 and EN 12811.
The main criteria side by side
| Criterion | Facade scaffold | Mobile tower |
|---|---|---|
| Working area | continuous along the facade, several lifts | one platform, usually 2–3 m long |
| Height | as documented and tied, also on tall buildings | outdoors up to 8 m platform height, indoors up to 12 m |
| Ground | uneven ground handled with jacks and sole boards | must be level and firm for moving |
| Standing time | days to months | hours to a few days per position |
| Trades | several at once | usually one person or a small team |
| Fixing | ties into the facade | none; stabilisers and ballast |
| Wind | taken by the ties | wind limit in the instructions, tower must be secured |
Worked example: a few windows or the whole house
Consider a detached farmhouse with three accessible elevations totalling about 34 m and an eaves height of 6 m. The front is paved, the back faces a lawn, and one side has a raised terrace with three steps.
Job 1: repaint four upstairs window frames on the paved front. Two days of work on level ground. A tower with a platform at around 4 m does it: set up once, moved three times, done.
Job 2: wash, prime and paint all three elevations up to the eaves. A tower with a 2.5 m platform covers roughly 2.5 to 3 m of wall per position if you lean a little to each side. For 34 m that means about 12 or 13 positions. Each height needs four passes (washing, priming, two coats), and the platform only sits at one level, so 45 to 55 moves are realistic. Each move means clearing the platform, unbraking, pushing, levelling and braking. And on the lawn and the terrace steps the tower cannot be rolled at all.
A facade scaffold for the same elevations, at about 36 m length and 7 m height, comes to roughly 250 m². It takes longer to put up, but afterwards every square metre is within reach and the painter works through the passes without interruption. At this size the facade scaffold is clearly the better tool. The scaffolding calculator turns those measurements into a parts list, and the method behind it is explained under calculating scaffold area.
When each one makes sense
The mobile tower
- Interior work: ceilings, lighting, ventilation and electrics in halls, stairwells and rooms. The floor is level, the tower moves fast.
- Spot repairs outside: clearing a gutter, replacing one window, fixing a wall light, patching a crack.
- Where ties are not allowed: sensitive facades or glazing, provided height and wind permit a freestanding tower.
The facade scaffold
- Large continuous areas: painting, render, insulation or brick slips across whole elevations.
- Work at the eaves and on the roof: roofers need a catch platform with a protection screen, which only a facade scaffold with the right components provides.
- Several trades in sequence: roofer, plumber and painter all use the same platform.
- Difficult ground: slopes, beds, steps and light wells are bridged once with jacks, compensation frames and lattice girders.
- Greater heights: above a second storey, towers soon reach their outdoor limits.
- Material on the platform: bags of render, insulation boards or bricks need a continuous deck in the right load class.
More on configurations and components is on our facade scaffolding page.
The ground often matters more than the height
The data sheet of a tower states a maximum height. On site, it is more often the ground that stops you. Castors need a level, load-bearing surface so the tower can be moved and braked safely. On grass the wheels sink in, on gravel they jam, and on a slope an unbraked tower starts to roll. Small gradients can be taken out with the adjustable legs above the castors, but that has to be redone at every new position. How castors and their brakes work is explained in the glossary entry on the scaffold castor.
A facade scaffold is more forgiving. Base jacks on load-spreading sole boards stand safely on grass or compacted gravel, and level differences at steps or slopes are dealt with once during erection.
Stabilisers also need room. They splay out from the tower to widen its footprint, and right against a wall, between a bed and the corner of the house or on a narrow path, there is often no space. Some systems permit stabilisers on one side only against a wall, but only if the instructions say so.
Safety in use
For towers, a few rules apply everywhere:
- Move the tower only with nobody and nothing loose on the platform, slowly and on level ground.
- Brake all castors and check the tower is plumb before anyone climbs up.
- Never leave out stabilisers or ballast because the job is short.
- Climb inside the tower via the built-in ladder and trapdoor platforms, never up the outside.
- Observe the wind limit; secure or dismantle the tower when wind picks up and at the end of the day.
- No ladders, boxes or buckets on the platform to gain height.
For facade scaffolds the key points are the tie pattern, a closed edge on every open side, made up of two rails plus a toe board, the correct gap between deck and wall, and safe access. How often the finished scaffold is inspected is a matter of national law. British sites work to the Work at Height Regulations 2005: a check before the scaffold is first used, then weekly at the latest, and once more after storms or anything else that could have weakened it. American sites follow the federal scaffold rules (OSHA 29 CFR 1926 Subpart L), with a competent person looking it over ahead of every shift. In other countries your local authority or safety adviser will know the rules. More on fixing is in our guide to scaffold ties and anchoring.
Combining both, and deciding in five steps
Often the best answer is both. A facade scaffold runs along the street side and the eaves side, where roofer and painter work; a tower handles the small gable above the carport and the stairwell inside. Some frame systems also allow a mobile tower to be built from frames with castors, but only where the instructions describe that configuration, including stabilisers, height and ballast.
When comparing cost, include labour: a tower has far fewer parts, but on large areas the relocation time eats the saving.
- Measure length and height. Add about 2 m reach to the platform height to get the working height.
- Estimate the duration: one day at one spot points to a tower, weeks at many spots to a facade scaffold.
- Walk the ground along the wall: level, firm, free? Note beds, steps, light wells and bins.
- Count the trades: one person, or roofer, plumber and painter one after the other?
- Clarify protection: roof work needs a catch platform; a footpath below needs a fan and barriers.
If you are unsure, send us dimensions and photos through the contact page and we will suggest a setup.