Replacing a downpipe? Choose the right scaffold.

For this job the Altrex RS51 is the one to book: 75 cm across, with lifts starting at 4.2 metres and topping out at 14.2 metres of reach, of which you use a slice. What settles it is not the width of the deck but the width of the way in. A rainwater line often hangs in an alley or behind a gate, and you have to get past there carrying full pipe lengths on your shoulder. Every version sits side by side in the list of towers available to hire.

The 135 cm wide model would hand you more room to lay things out, and on a vertical run that buys you little in return. You do not need a second working surface, you need a steady stand in one spot with room for your feet. A room scaffold does not enter into it, being made for indoor work and unable to reach a house gutter. The one person single user tower for light jobs is out too, because there are usually two of you here.

The 245 cm platform earns its keep as a halfway store. A pipe section, a handful of brackets, the cordless drill and the tools for the top connection lie next to each other while you still walk round them. In zinc you add your snips and a file; in plastic your solvent cement and a marker pen. Without that space you carry everything up in your pockets, and nobody keeps that up for half a day when replacing a downpipe on a house of two storeys.

The top of your reach is the outlet in the base of the gutter rather than the roof edge, together with the bend clipped into it. On two storeys that sits four to six metres up, which calls for a stand of six to eight metres. That figure combines the height of your deck with the roughly two metres you cover standing with your arms up. The matching stand is described under an eight metre build, worth reading before you settle on a working height.

Make sure you can also reach a little above the outlet itself. You have to get a pair of grips in there, clear away the old sealant or solder, and push the new bend up from underneath. Stand exactly at eye level with the outlet and that pushing up will not happen, because you need movement above the connection point. Half a platform height more is the difference between comfortable work and levering away at arm's length all afternoon.

Take your starting level where the castors will stand. Beside a rainwater outlet that is nearly always the lowest paving on the whole plot, because the slabs fall towards the gully. If that puts you half a step below the rest of the terrace, it counts towards your height all the same. Torn between two lifts on a wall of two residential storeys, take the upper one; a shortfall of half a metre announces itself only when the deck is already built and the parts are all spoken for.

At the foot the pipe discharges over a trapped gully, a cast iron pot or a ground pipe set into the paving, and that is precisely where you want neither a castor nor a stabiliser. When replacing a downpipe you also have to get at that shoe, since the bottom connection is usually renewed along with the rest. Set your stand half a metre to one side of the pipe line, so the base stays clear and you still come out square with the outlet.

Then look at how you get material past. New pipe comes in sections you carry on your shoulder, and a gate or a tight passage forces you to fetch them one at a time. If the gully sits in a border or among decorative setts, a stabiliser foot will sink there under load. A wide board gives it something to bear on; and how to handle a sloping or a loose surface is covered fully in this explanation of ground conditions.

Clear out the permanent residents of that corner before the tower turns up. Round a rainwater line those are a water butt with an overflow, a gravel tray, a crawl space hatch, a fence running tight past the pipe and sometimes a meter cabinet fixed to the wall. Look upwards too: an extension or a canopy jutting out halfway decides whether your stand can sit against the wall at all. Check that before you fix a delivery date with us, because a stand that cannot reach the pipe is no use to anybody.

Material choice drives your planning here more than height does. Plastic moves quickly: cut sections, deburr, solvent weld into a socket, push home, and fix brackets as you go along. Zinc is slower, because you cut to size, fold or solder, and zinc forgives no second attempt on the same seam. One complete run in plastic normally fits into two hire days; pick zinc for the new line and you add a day as standard and keep a margin at the end.

On top of that come the building and the striking of the tower, plus time for cutting out and making good the old bracket holes. If there is a second pipe at the back, or the gutter outlet itself has rusted through and has to be renewed as well, the work doubles while the height stays exactly the same. Reckon on four hire days rather than three then, because you would rather not leave a half fitted line hanging over the terrace overnight.

Allowing that margin costs surprisingly little. The full tariff applies to the first day only; every day you add after that is ninety five per cent cheaper. Building in a spare day therefore barely touches the rental price, while booking too tight means solvent welding in the dark with a torch in your teeth. To sharpen that estimate before you hire, read how the number of hire days is worked out for a job that runs across several days rather than a single morning.

The work of replacing a downpipe runs from the top down along one vertical line. You hang the bend in the gutter outlet first and fix the topmost bracket, because that point settles where everything beneath it lands. From there you drop a plumb bob or stretch a taut cord to the paving, and you drill the rest along that line. A pipe two centimetres out of plumb shows across two storeys, and straightening it afterwards means drilling fresh holes in mortar you have only just made good.

Repositioning here goes downwards rather than sideways, and that is the big difference from wall work. You fit the top section from the highest stand, take a platform out and finish the middle, and the last few metres you simply do standing on the slabs. Clear the deck completely before every change. A loose pipe section, a box of brackets or a tin of cement has no place on a tower you are about to lower, however brief the adjustment.

Carry one section up at a time and hold it upright against your body as you climb. With zinc you wear gloves, because cut edges stay sharp; with plastic what counts is a clean, dry face on the joint, so wipe the socket and the pipe end before you press anything together. Finish above the gully with enough play left, so the shoe can be taken off later without dismantling the whole run. That small piece of foresight saves a future hire period at the same corner of the house.

You receive the tower as separate components, counted off in advance: uprights, braces, platforms, guard rails, castors and stabilisers. Settle in advance where that stack is to land, and keep the run underneath the pipe entirely free, because you will lay your new lengths out there in order. A reservation placed on a working day, with the afternoon deadline of three o'clock still ahead of you, means the set is standing at your address the next working day, in good time to sort everything through.

The date it all arrives and the date it may go are both yours to choose. It is most convenient to have the tower come on the morning your pipe, bends and brackets also land, so you can spread everything out and sort it in one go. Assembly belongs to you: with two people, the manual beside you and the fitting video on your phone, you reach working height quickly enough here. If you would rather fetch it, the yard at Zeeburgerpad 89 in Amsterdam hands the set over free of charge by arrangement.

Once the new line hangs, we drive the components away again. You dismantle, count as you go and set the complete lot out at the agreed place. Hold off striking until you have watched the pipe run through under a shower or a bucket of water tipped into the gutter, because putting it right from the ground is not possible. Hold the last section back until you are sure of the fall. What carriage in your own province amounts to is shown at the fixed regional delivery rates.

Your platform answers to EN 1004, load class 3, meaning a bearing capacity of two hundred kilos for each square metre of deck. When replacing a downpipe that mounts up faster than you expect: you, someone passing material, a drill, a box of brackets and a couple of metres of zinc besides. Spread the weight across the floor and put the heavy box in the middle, not in the corner you are also leaning over to drill.

None of the standing rules bend for this job. Wheels braked before anyone steps on, nobody up top while the tower is being moved a short distance, and work stops as soon as it starts blowing hard. That last one weighs heavily here, because a pipe length held upright behaves like a sail and can shove you half a step sideways. Every rule that applies on a hired tower is gathered at safe working at height, worth ten minutes before the first lift goes up.

The dangers specific to this work sit in the old material. A zinc pipe you pull open has edges like a knife, and a rusted bracket snaps without warning so that you can lurch backwards. Lower released sections rather than dropping them, particularly with the gully open below you. Drilling dust and wet leaf litter out of the old pipe make your floor slippery as well; sweep that off before you turn round holding a long length of pipe in both hands.