Temporary Works and Site Enclosures in Timber
Temporary works are the one construction on site that nobody draws and everybody walks through. They exist to protect people and finished work, and they are almost always assembled from offcuts by whichever crew has the least time. Treating them as a construction — with a drawing, a check and someone responsible — costs little and changes the number of accidents.
Overview
TAV. 00The process covers hoardings, edge protection, opening covers, pedestrian routes and protection of existing finishes built from timber panels, from planning alongside the programme through to dismantling and reuse. The logic holding the phases together is that temporary works are not an accessory to the site but a time-limited part of it: they have an erection date, a dismantling date, a design load and a person answerable for their condition. The governing constraint is almost always wind, because a solid hoarding is a continuous surface that no self weight can hold down. The recurring defects — overturning, displaced opening covers, guardrails on inadequate supports — all come from the same cause: something temporary treated as something improvised.
The site score
TAV. HThe detail of the craftFour data for every arrangement
Plan the temporary works with the programme
Every arrangement gets a record sheet with four data: where it is, from when to when, what load it has to carry and who answers for it. The sheet is built by reading the works programme, because protection is needed at the moment the risk arises, not when there is time to build it. In the same step it is decided what is bought, what is hired and what is built from panels, and the store is identified where sound panels will return at the end of the contract.
Preparation of record sheets for the temporary arrangements stating location, service period, design loads and responsible person, coordinated with the works programme and the safety plan.site notebook — editorial synthesis
click a beat · arrow keys ← → walk the site · dashed pauses are the chemistry at work
PLATE 01
A solid hoarding is a wall of wind
Mesh lets air through and takes almost no load. A continuous panel takes it all, and its self weight is far too low to resist it: stability comes entirely from ballast and anchorages.
The diagram illustrates the logic of the problem. Design actions, ballast quantities and stability checks are to be taken from the design, the safety plan and the applicable standards.
PLATE 02
The three protections that cannot be improvised
Edge, opening and route are the three points where badly made temporary works cause immediate harm. In all three the defect is not the absence of protection but its fixing: something that shifts without anyone noticing.
The diagram illustrates the three cases in their logic. Sizing, heights and performance requirements are to be taken from the safety plan and the applicable standards.
How it ages (and what betrays it)
TAV. PQuestions from the site
TAV. QOSB or plywood for outdoor temporary works?
It depends how long the job lasts. OSB costs less and is perfectly good for short periods and sheltered positions; plywood with a moisture-resistant glue line handles wetting cycles far better and pays on long contracts, where the cost of the panel is spread over several reuses. The criterion is not the purchase price but the number of times the panel will come back to the store.
How long does an OSB panel last outdoors?
Much less than the site expects, and degradation starts at the cut edges, not on the faces. One season outdoors with unprotected edges is already enough to produce swelling and the beginning of delamination. Sealing the cuts and capping the top of the hoarding with a flashing extends panel life far more than any coating of the faces.
Does a site hoarding really need a drawing?
It needs at least a sketch with position, height, ballast type and anchorage points. This is not bureaucracy: it is the only way the erecting crew knows how many ballast units are required, and the only way someone inspecting later can count them. A hoarding with no sketch gets built from whatever is on hand, and nobody can say whether it is enough.
Can formwork panels be reused as hoarding?
Yes, and it is good practice, but with two caveats. The first is that a panel coming off the formwork is soaked in release agent and does not take paint or adhesive signage well. The second is that each one has to be checked individually: a panel that has already worked in bending under a pour may have internal delamination that is invisible at the surface.