Removing window frames? Choose the right scaffold.

Demolition tempts people to grab the widest model, but with window frames that works out wrong. The old window frame does not go down over your deck; it tips inwards and leaves the house by the stairs or the balcony. What you need outside is reach and stability, not a storage floor. For that reason you hire a mobile scaffold in the RS51 build, a build 75 cm across that passes between a skip and the wall. The full range of mobile scaffolds is shown model by model with the sizes.

That narrow width repays itself where things get crowded. On a demolition job there is a skip, a stack of plywood for boarding up and a barrow going to and fro. A tower of 135 cm then blocks precisely the gap you need, while at 75 cm you still get past everything. Through a gate to the rear elevation you also come with this model without taking parts off, and that saves you time at every move.

On the deck itself you need very little space: a multi-tool or reciprocating saw, a crowbar, a sealant knife, glass carriers and gloves that stand up to shards. The volume is in what comes out, and that goes the other way. If you work outside with two people because the frame is heavy, a deck 245 cm long is still ample to stand side by side without getting in each other's way while the stiles come free.

The point you have to reach lies higher than the window frame itself. Above the head sit the sealant joint, the junction with the brickwork and sometimes a timber trim that has to come off first. That is where you cut, so that is where you measure to. For windows on the first floor of an ordinary house that point lands between 6 and 8 metres. Counted from your platform height there is about 2 metres of reach on top, so the deck stays well below the top of the opening to come.

Measure from the street level or the garden path the castors will stand on. If a skip is already at the door, allow for your build having to go a metre further along, on ground that lies a touch lower or higher. On a corner house the front and side elevations often differ in height, so measure both separately before you fix anything. Which build belongs with that is worked out on the page about a reach of eight metres.

Choose too low and you find out at the worst possible moment. The bottom is already free, the frame still hangs on its top corners, and that is just where your saw will not quite reach. Climbing down to raise the build is no longer an option, because the hole cannot be left standing half open. So take the build that comes out one level higher and work from a deck where you saw with bent arms rather than stretched.

On this job you share the space in front of your house with a skip, and the order matters. The skip goes where the lorry can drop it, and your build shuffles round that. So decide first where the container stands and only then where the mobile scaffold goes, or on demolition day you will be shoving a build that is already up. Between skip and wall keep at least the base size plus the spread of the stabilisers free.

The ground turns messy of its own accord in demolition. Lumps of brickwork, old sealant and pieces of timber come down, and they gather exactly under the place where you stand. Sweep that strip at the end of every working day, because one stone under a castor puts your whole build out of true. If part of the tower comes onto the footway, leave a lane for people to pass and check locally what is permitted in your street with a skip there as well.

Think about the route indoors too. The loosened frame goes down through the room, so inside you need a clear line from the window to the front door. Outside you want that same clear line from your build to the skip. If those two routes cross, you spend the day walking round your own material and lose a quarter of an hour on every frame. Setting a tower on a bumpy or falling surface is covered in the explanation about uneven ground.

Reckon per window frame on this job and not per elevation. An ordinary casement with single glazing is out in a morning; a wide frame with fixed glass, a soldier course over it and a concrete cill beneath costs you a whole day. Add the boarding up to that, because it belongs to the same day. Four frames upstairs therefore means two to three days in practice on which the mobile scaffold has to stand there, and not one long demolition day.

On top of that you seldom land exactly right. A frame held by anchors instead of screws costs an hour extra, and a pane that will not come out whole costs another. So do not plan through to the final day, but always keep a spare day in reserve for that kind of setback. If the new frame only arrives the week after, you go on hiring until the temporarily boarded hole may be opened again for fitting.

Those extra days barely weigh in the rental price you pay. Your reservation is at its dearest over the opening twenty four hours, and from then on the daily rate falls away by 95 per cent. A spare day therefore costs you almost nothing, while a tight booking saddles you with a boarded up hole and no build left to open it with. That always costs more than the day you thought you were saving. Judging your period further is covered in this piece about hire days.

Always start with the glass. A pane still sitting in the frame while you pull at the stiles is the most dangerous part of this job. Cut the sealant free, take the beads away and lift the pane inwards with two people and glass carriers, not outwards over the guard rail of your build. On a deck of 245 cm the two of you stand either side of an average window without having to pass one another.

Then comes the cutting free. You saw through the stiles, lever the anchors or screws out and push the frame inwards. Outside you hold it back so it cannot tip out; inside somebody catches it. Take everything you need for that up in one go, because climbing down halfway through a part finished removal is exactly what you want to avoid. A bucket holding crowbar, sealant knife, saw blades and screwdrivers stands more stably than loose items on the deck.

Think ahead about the boarding. Cut the plywood to size before you take the window frame out, and lay the sheets ready beside the build, not on it. The hole then stands open for half an hour at most. Only move the mobile scaffold once the opening is shut and taped, never in between. If new frames are going in, the same build stays up for fitting the new window frames, which saves you a second day of assembly.

You are supplied with a complete set of parts, counted and bundled, and you build it yourself. We come to assemble nothing and never deliver a frame put together; there are building instructions with it and a video that keeps to the same order. With two people you are standing up top inside an hour. Plan that hour on the day before the first demolition day, because you do not want to begin sawing while the build is still to go up.

Complete a reservation on a working day with 15:00 not yet passed, and the delivery date becomes the next working day. Choose your delivery day so the material is there ahead of the skip, since once that container stands the best position is often taken. Anyone driving themselves agrees a time and collects the set free of charge on the Zeeburgerpad in Amsterdam, though most people on a demolition job prefer delivery, as there is enough carrying to do already.

For the collection date the same principle holds: you fill it in yourself and may move it while the material is still free. Only have the mobile scaffold taken away once all the holes are shut or the new frames are in, because ordering again means building again and so half a day lost. Reckon the transport into your budget for this job. Every province has its own fixed amount for the run out and the run back, listed together in the overview of delivery rates.

You work on a deck that may take 200 kg to the square metre, and load class 3 in EN 1004 is exactly what that figure stands for. On this job you reach that sooner than you think: two people, a box of tools and a pane you set down for a moment add up quickly. So never stand removed glass on the platform but pass it straight inside. The same goes for the cut out frame, which by its length starts hanging crooked the instant you let go.

The brakes go on as soon as anybody stands up there and stay on until the working day is over. Do not move your build with tools or material on it, and stop cutting loose the moment the wind gets up: a half detached frame caught by a gust will drag you with it. After every move go round the four stabilisers again and press each one firm against the ground. The remaining rules sit together in the article on working at height, and on demolition they are no luxury.

What sets this job apart is what can come down. Glass fragments, lumps of sealant, anchors and pieces of timber drop straight into the zone where the skip stands and where people walk by. Fence that strip off with tape or cones before you begin, and keep it fenced until you are done. Work in cut resistant gloves and safety glasses, and sweep the deck clear of shards at the end of each day. A splinter under your sole otherwise goes back up with you.