Precast Concrete Erection and Installation Insurance

Precast erection has a window in every unit's installation where nothing permanent is holding it, and that window is the whole safety case.

A unit is landed, plumbed and propped, and the crane is released. From that point until the connection is made and has gained strength, the unit stands because of temporary propping, bracing or a tie back to something already stable. The recognised failures are a prop on an inadequate base, props removed to get access for a following trade, a brace omitted because a unit looked stable, a frame erected beyond the extent the bracing scheme allowed, and a connection grouted and propped off before the grout had cured. Any of those can take out a single unit or a run of them.

So the erection sequence and the propping scheme are the documents that matter, and they need to be followed rather than consulted. A scheme that states the propping and bracing for each stage, the maximum extent of frame that may stand before tying in, the curing time before props come off, and a rule that nobody removes a prop without authority. Then a record at each stage. A contractor whose file shows a scheme and sign offs is in a very different position from one whose erectors made sensible decisions.

Precast arrives to millimetre tolerances and lands on a structure built to construction tolerances, and that mismatch causes a surprising share of this trade's disputes.

A unit needs a bearing of a specified length, at a specified level, on a surface that is flat and sound. In practice it arrives at an in situ concrete wall cast slightly out of position, a steel beam set a few millimetres low, masonry that is not level, or a pad that has the wrong bedding. The options are then packing it, which may be outside what the design allows, refusing to erect, which stops the job, or proceeding and hoping, which is how a short bearing ends up in a finished frame where nobody can see it.

So the survey before erection is the protection and it is quick. Check and record bearing levels and dimensions before units are lifted rather than discovering them with a panel on the hook, raise anything outside tolerance in writing before erecting, and get an engineer's instruction where packing or a modification is needed. Where a main contractor presses to erect onto a bearing you have flagged, that instruction belongs in writing, because a short bearing discovered years later is examined against who installed the unit.

Precast is manufactured rather than built, which changes what damage costs.

A unit chipped on a corner, cracked by a bad lift, dropped, or damaged in transit cannot be made good on site in the way an in situ element can. It goes back to the factory to be remade, and the frame stops at that point in the sequence because precast erection is linear: you cannot generally skip a unit and come back. So the loss is the unit plus the crane standing plus the gang standing plus the programme, and on a tight site with a booked crane that is a substantial figure for a chipped corner.

So handling is where the money is protected. Lifting only by the cast in inserts rather than by a convenient point, slings and spreader beams appropriate to the unit rather than what is on the lorry, units stored and stacked as the manufacturer specifies with correct bearers, inspection on delivery with damage recorded and rejected before it is lifted, and care at the final placement where a unit is swung into position against something already built. Transit damage recorded on arrival is the difference between the haulier's problem and yours.

There is no part of precast erection that does not involve a crane, which puts this trade inside the lifting question whether it wants to be or not.

Every unit is lifted, frequently at or near the crane's capacity at that radius, over a live site, with the gang working beneath to receive it. That brings the whole lifting apparatus with it: appointed persons, lift plans, ground bearing for the crane, slinger competence, and above all the distinction between a contract lift and crane hire with operator, which decides who carries a lifting failure. Precast erectors sit on the hiring side of that question and frequently do not know which basis they are on.

So establish it per job rather than per relationship. Confirm in writing whether the crane comes as a contract lift or as hire with operator, and if the latter, understand that the lift planning, the appointed person and the responsibility for the operation are yours. Make sure your own people hold the competences that implies. And check the policy covers the lifting operation on the basis you actually work, because a contractor providing the appointed person under a hire arrangement carries more than one that buys contract lifts.

Temporary stability and the lifting basis decide this one. We are an FCA regulated broker and will not tell you we are the best choice. These are the questions that decide it.