Plastering a stairwell? Choose the right scaffold.

For this job the model you pull out of the hire fleet is the Altrex RS44 room scaffold. It is an indoor build reaching four metres, and every loose component slides through an opening from about seventy centimetres wide. That last figure is no footnote when you are plastering a stairwell. The whole set travels through the front door, past the meter cupboard and up the flight, and a component that snags in the hallway cannot be sawn shorter. Walk that route with a tape before you reserve anything.

What weighs heaviest here is the surface your tub stands on. A tub filled with render is a serious weight, and you want it beside your boots rather than climbing down for a fresh scoop every few minutes. A closed deck with a guardrail around it gives you that spot; a pair of steps bridging two treads does not. You also need to swing a two metre straightedge without catching it on anything, and that alone rules out most of what people already own for indoor work.

Against an outside wall you would hire a mobile scaffold and think no further, but indoors the door frame decides what fits. For a stairwell you therefore always land on the room model, usually with adjustable legs so the feet can sit on different treads. Getting through the doorway is the first condition of any indoor job; height and platform come after that. Sizes and builds are set out on the page about the room scaffolds in our hire fleet, where you can also see what extra width does and does not buy you.

Your highest point is the top edge of the shaft, where the render runs up against the landing ceiling or the trim below it. Measure to that edge from the level your set-up will actually rest on, which on this job is the landing with a few treads beneath it, not the hall floor a storey below. Anyone who measures from the bottom of the house orders a build one stage too tall, and a build one stage too tall no longer slots into the shaft at all.

We express every build as working height, which is the platform height plus roughly two metres of reach from where you stand. For a shaft in an ordinary house that puts you between three and four metres, which is exactly the span this indoor model covers. Within that range, pick the stage that leaves the top edge of your surface at eye level or a fraction above it, because that is where a trowel travels most calmly. For comparison, look at the build that reaches four metres.

Stand a stage too low and you lay the top band with your arms above your shoulders, and that shows up later in the flatness of the wall. Render gives you no second chance the way paint does: once the mortar has pulled in, the whole pass has to belong together. Hiring one stage higher saves you no time at all on the day, but it saves you a surface that ripples, and you notice the difference again when you move on to the walls on the first floor.

The single biggest choice on this job is where you mix. Do it up on the landing and not down in the hall, because lifting a full tub up a flight is exactly the movement that puts people on their backs or on their knees. Stand a bucket of clean water next to it, lay a board under your mixing gear, and arrange things so that you can reach your material from the deck without descending. That is what keeps a pass on the wall running from corner to corner without a break in it.

That does mean the landing has to be emptied. Cupboards, laundry baskets and the bedroom doors that open onto it all have to go or be wedged shut, because you need that space for the mixing station, for the bags of dry mortar and for the footprint of the scaffold itself. Lay sheeting with turned up edges over the whole landing and over the top few treads. Mortar that dries on a timber tread will not come off again without taking some of the wood with it.

Do not forget the flight itself. The treads under your set-up are your only way down and you want them clean and dry even when you are in a hurry. If you are hiring adjustable legs because the four feet land at different levels, check how solid those treads are first. A tower standing on stepped timber simply asks for more care in the levelling than the same tower would on a flat bedroom floor. What that involves is explained in this piece on working over a stairwell void.

Render in a shaft is planned in passes rather than in hours. You lay the upper section in one continuous movement, close it up, and leave it; the lower section follows the next day from a lower stage. Two passes, in other words, with a night in between. Add the build day, plus the day on which you close everything up and take the tower down, and three to four hire days is the honest figure for a house stairwell, with the scaffold standing all the way through it.

Drying behaves differently here from drying in a room. Warm air collects at the top of the shaft, so the upper section feels firm while everything down by the hall floor is still clammy. Count on the lower part needing longer and plan your last day around that. Ventilation helps, but too much draught across a fresh face brings hairline cracks instead, so do not throw every window in the house open at once, however impatient you may be about starting the second pass on the lower half.

An extra day costs very little once a scaffold is on hire with us. The full rate applies to your opening period of twenty four hours only, and a discount of 95 per cent then runs on every following day, so waiting for mortar to harden is not an expensive decision at all. What does get expensive is booking too short a period: the shaft is still damp halfway down while the collection van is already on its way. There is more on this in our note on sensible hire periods.

Your working floor is 245 cm long, and that number decides where you split the surface in two. Across the width you will usually take the whole wall face from one position; up the height you will not, so you go looking for a horizontal line where the two passes can meet. Do not pick that line at random in the middle of the wall. Choose somewhere that already exists: just under the handrail, level with a door head, or precisely in the internal corner of the shaft.

Upstairs, finish the entire upper section first, corner to corner, in one unbroken pass. Feather the bottom edge of it a little thinner and the second pass will meet it cleanly the following day without leaving a ridge. Keep your straightedge lying flat on the deck rather than propped against the guardrail, because aluminium against steel slides away the moment you look elsewhere. And keep the tub in the middle of the floor, never on the edge beside the open void, where a knock sends it straight down into the hall.

For the lower section you drop a stage and shift the set-up down along the string. Before you start, check that the meeting line is still clean; an edge that has begun to fluff up gets sanded back first. Make sure everything you need travels up with you in one trip, because stopping halfway through to fetch a tool is how a pass ends up with a cold joint. If the adjoining rooms follow, plan the wall surfaces in the bedrooms as a separate stretch.

What arrives is a counted set of loose components, not a standing tower. Decide in advance where that pile is going to land, because when you are plastering a stairwell the hall will soon be holding your bags of mortar and your tools, and the flight has to stay clear as the route upstairs. An empty room on the ground floor works best, particularly if it is raining. Reservations completed on a working day before 15:00 arrive as loose parts on the next working day.

You name the delivery date and the collection date yourself. Take a delivery day a couple of days ahead of your first pass, because you need time to build, to sheet the stairs and to set up the mixing station. Putting the tower together belongs to your side of the job rather than ours; the printed manual sits in with the parts and an instruction video walks through the order in which they go together. The stage by stage guide to putting a tower up covers what to watch for on the landing.

Once the render is on, you take the tower apart and stack the complete set on the ground floor, and we pick it up from there on the date you gave us. If you would rather drive over yourself, collection by appointment is free of charge at Zeeburgerpad 89, 1019 AD Amsterdam, so long as your vehicle will swallow the longest components. Fixed rates per province are listed under the charges for bringing and fetching, so nothing about the total shifts once the work is behind you.

Every square metre of your working floor may carry 200 kg, the figure listed as load class 3 in EN 1004. On a plastering job that number is not a formality: a filled tub, a bag of mortar, you and your tools add up faster than you would guess, especially with somebody standing beside you to hand things across. Spread what you carry over the full length of the floor instead of stacking everything into one corner above the open void, where the load sits worst.

If there are castors underneath, they go on the brake before anybody climbs, and you only move the tower with an empty deck. When plastering a stairwell that is a rule you keep to even when it means carrying a tub down to the landing first. The ground under this set-up is a flight of stairs, after all, and a flight of stairs is nowhere level. Level up again after every move you make and check that each deck section has dropped back into its catch before you load it.

The real hazard stays the drop through the void. A tool that slides off your floor lands on the hall floor a storey below, so trowels and the straightedge lie flat rather than leaning on the guardrail. Fresh mortar also turns a deck section greasy, so wipe splashes away before they pull rather than at the end of the day. Agree with the household that nobody walks under the tower while you are up there, not even for a moment. The rest is set out in the guidance on indoor work at height.