Study notes — Erect and dismantle formwork for footings and slabs on ground

What this unit is about

Formwork is the temporary mould that holds wet concrete in shape until the concrete can hold itself — this unit covers planning, setting out, building, checking, stripping and re-stacking the edge forms for footings and slabs on ground. Get it right and the slab pours straight, level and to size; get it wrong and the mistake sets in concrete.

To be assessed, you'll erect and dismantle formwork for a slab on ground of at least 30 m², at least 100 mm thick, with an edge rebate and an internal corner. These notes cover everything that job asks of you.

1Stage one

Plan and prepare

Read the drawings and work instructions first, and plan the sequence of the job — set out, build, check, pour — so nothing gets done twice or out of order.
Plan the work to comply with everything that applies: WHS laws and regulations, the National Construction Code (NCC), relevant Australian Standards, environmental requirements, manufacturers' specifications and your workplace's own procedures. The project drawings and specification are the final word on sizes, levels and details.
Select your tools and equipment and check serviceability — blades sharp, guards fitted, leads tested and tagged, nail guns working properly. Report or tag out anything faulty; never push on with damaged gear.
Choose PPE for each part of the task and change it as the task changes — eye and hearing protection when cutting or nailing, gloves for rough timber and steel pegs, and whatever the site or SWMS calls for.
Inspect the site before set-out. Locate underground and overhead services, spot the hazards (excavations, mobile plant, uneven ground, weather), apply risk controls, and put up the required signage and barricades.
Work out materials from the drawings — measure the perimeter and form heights, calculate quantities of boards, pegs, braces, fixings and release agent with a sensible waste allowance, then handle them safely and stack them close to where they'll be used.

2Stage two

Erect the formwork

Clear the work area and prepare the surface — forms need a firm, even base or they will move the moment concrete hits them.
Measure, set out and level from the datum and building lines on the drawings. Run string lines, set the top of every form to the finished slab level with a laser or level, and keep the edges straight to the line.
Fix and fasten for stability — boards nailed or screwed to pegs, joints cleated, corners tied together. A form that flexes now will blow out under wet concrete.
Construct and fit the edge rebate former where the drawings call for one (commonly where brickwork sits down onto the slab edge). Its size and position come off the detail drawing, never off memory.
Check for square and dimension, then brace. Equal diagonals or the 3-4-5 method prove square; confirm every dimension against the drawings before bracing the forms to hold line and level right through the pour.
Install block-outs and cast-in services — penetrations, hold-down bolts, plumbing and conduit sleeves — exactly where the drawings put them. They cannot move once concrete is poured.
Apply release agent to the form face following the manufacturer's specifications — before the reinforcement goes in, and never slopped onto the steel.

Slab-edge formwork in section — the build order, from base to pour.

Press play to watch the build order, or step through it one part at a time.

3Stage three

Strip the formwork and prepare it for reuse

Strip only when directed — the concrete must be strong enough to hold its own edge before the forms come off.
Strip edge boxing and bracing sequentially and safely, roughly the reverse of the build order. Lever against pegs and the ground, never against the fresh concrete edge (the arris) — it chips easily and can't be un-chipped.
Check every component for reusability. Sort what can go again from what's had it, and dispose of damaged pieces to meet safety and environmental requirements — not into the general skip if the site sorts waste.
De-nail, clean, oil and stack. Pull nails the moment a board comes off (a hidden nail in a stacked board is a hand injury waiting to happen), scrape off slurry, re-oil the faces and stack or store components flat, ready for the next job.

4Stage four

Clean up

Clean the work area to legislative and workplace requirements — sort waste for reuse, recycling or disposal, handle materials safely, and keep concrete slurry, washout and release agent out of drains, soil and waterways.
Check, maintain and store tools and equipment — clean them down, coil leads, oil what needs oiling — and report any faults so they're fixed before the next job, not discovered on it.

Know this cold

The background knowledge an assessor expects you to carry in your head:

Rules and standards. The NCC sets the requirements for footings and slabs on ground; relevant Australian Standards — AS 3610, Formwork for concrete, is the key one — govern how formwork must perform. Your forms must produce concrete to the tolerances the documents call for.
Workplace quality. Sites set their own quality policies: tolerances on line, level and dimension, and hold points — typically a check and sign-off of dimensions, levels, rebates and cast-ins before the pour. Know your site's procedure.
Safety. The big hazards: manual handling of boards and pegs, nail guns and power saws, swinging sledgehammers, protruding nails, working near excavations and plant, dust when cutting formply, and trip hazards from offcuts and pegs. Controls: serviceable gear, the right PPE, good housekeeping, signage, barricades and exclusion zones during the pour and the strip.
Environment. Contain release agent and fuels, no slurry or washout to stormwater, sediment controls in place, and timber waste segregated for reuse or recycling.
Line, level and plumb. Edges straight to the string, top of form at design level everywhere it's checked, faces plumb so the finished slab edge is vertical. All three, everywhere, before anyone orders concrete.
Drawings and symbols. Site plan for position and levels; footing/slab plan for dimensions; sections and details for edges, rebates and set-downs; the specification for concrete, tolerances and release agent. Read RL (reduced level), FFL (finished floor level), datum marks, centrelines, section markers — and remember dimensions are in millimetres.
Set-out and quantities. Work from the datum and building lines, measure twice, square with 3-4-5 or equal diagonals. Board length ≈ perimeter plus laps and waste; pegs ≈ perimeter ÷ spacing, plus extras at corners and joins; release agent by the maker's coverage rate.

Tools, gear and materials — quick reference

Item	What it's for	Check / characteristic
Formply (film-faced ply)	Edge boards; smooth, reusable form face	Face undamaged; oil before each use
Sawn timber / LVL	Boards, cleats, braces, fillets	Straight, free of major splits
Steel or timber pegs	Hold boards to line and level	Sound heads and points; drive to firm ground
String line, laser & spirit level, square, tape	Set-out, line, level, square	Laser calibrated; tape hook not bent
Circular saw, drill/driver, nail gun	Cutting and fixing	Guards working, leads tested and tagged
Sledgehammer & wrecking bar	Driving pegs; stripping	Handles sound, heads tight
Release agent	Clean strip, protects the form face	Type and coverage per manufacturer's spec

Where people slip up

"The sides all measure right, so it must be square."

Correction: a parallelogram has the right side lengths too. Square is only proven by equal diagonals or a 3-4-5 check — do it before you brace, and again after.

"She'll hold — it's only edge boards."

Correction: wet concrete pushes hard, and a pump hose pushes harder. Peg at close centres, brace to solid ground, and watch the forms during the pour — a bulge caught early is a tap with a hammer; caught late it's a demolition job.

Applying release agent after the reinforcement is placed.

Correction: oil on the steel destroys the bond between reinforcement and concrete. Coat the form faces before the reo goes in, at the coverage the manufacturer specifies.

Stripping early, or levering the bar off the concrete edge.

Correction: wait for the go-ahead, strip in sequence, and lever against pegs or the ground — never the arris. Chipped edges are visible forever and expensive to patch.

Stacking stripped boards with the nails still in.

Correction: de-nail immediately, every board, every time. Then clean, oil and stack flat — reusable formwork is money; damaged formwork is disposed of properly, not left lying about.

Mini-glossary

Formwork: The temporary structure that moulds wet concrete to shape and holds it there until it sets.
Formply: Plywood with a smooth film face, made for concrete work — strips cleanly and reuses many times if looked after.
Edge rebate: A step formed into the slab edge, commonly so brickwork can sit down below floor level. Formed by a rebate former (fillet) fixed inside the edge board.
Block-out: A former that creates a void or penetration in the slab — removed after the pour.
Cast-in item: Anything fixed in position to be permanently embedded in the concrete — hold-down bolts, pipes, conduits.
Release agent: Oil or emulsion applied to the form face so concrete doesn't stick — applied per the manufacturer's specifications.
Datum: The fixed reference point on site from which all levels are measured.
RL / FFL: Reduced level — a height relative to the datum; finished floor level — the RL of the slab's top surface.
Peg: Steel or timber stake driven into the ground to hold form boards to line and level.
Brace: A diagonal member from the form to solid ground that stops the form moving under concrete pressure.
Set-out: Transferring the positions and levels on the drawings onto the ground — accurately.
Plumb: Exactly vertical. Line = straight; level = exactly horizontal; you need all three.
Arris: The sharp finished edge of the concrete — protect it when stripping.
Stripping: Dismantling the formwork after the concrete has gained enough strength — sequential, safe, and gentle on the edges.
SWMS: Safe work method statement — the documented, agreed way to do high-risk construction work safely.

That's the whole unit in one page. Read it again the night before your practical.