Study Notes — CPCCCO2013 Carry out concreting to simple forms

1

Plan and prepare

Set the job up right before a single peg goes in.

Read the work instructions first. Study the drawings and specifications, work out exactly what's being poured (size, depth, finish, falls), and plan the sequence of work before you start.
Plan to comply. Every part of the job must line up with laws and regulations, the National Construction Code (NCC), relevant Australian Standards, WHS and environmental requirements, manufacturers' specifications, workplace procedures, and the drawings and specs for the job.
Select tools and equipment for the task, check each item is serviceable (handles tight, blades sound, leads and plant tagged), and report any faults — never work with damaged gear.
Match your PPE to each part of the task. Wet concrete is caustic, so waterproof gloves and rubber boots at the pour; eye and hearing protection plus dust control when cutting; hi-vis, hard hat and steel-caps as the site requires.
Inspect the work site and locate services (power, water, gas, comms) before any excavation. Assess hazards, apply risk controls from the SWMS, and set up the required signage and barricades to keep others clear of the work area and wet concrete.
Select and calculate materials. Work out concrete volume and quantities of formwork, mesh, bar, chairs and plastic; handle materials safely (team lifts, mechanical aids) and position everything ready for use so nothing holds up the pour.

On the job: concrete doesn't wait. Once the truck or mixer starts, every shortfall in planning — a missing screed board, mesh not cut, no barricades — becomes a crisis. Prep wins pours.

2

Erect simple formwork

The mould decides the shape — get it straight, level and strong.

Prepare the substrate. Strip topsoil and organic material, excavate to the specified depth, and compact the base so it's firm, even and won't settle under the slab.
Review the formwork design from the drawings before building — check dimensions, finished heights, falls and datum points so the forms match the plan, not a guess.
Erect the formwork. Set edge boards to line and level using stringlines and a level, drive pegs on the outside, and brace so the forms won't bow or blow out under the weight of wet concrete. Check for square (measure the diagonals or use the 3-4-5 method).
Install the vapour barrier where specified: lap joins generously (around 200 mm) and tape them, turn it up at the edges, and repair any punctures before the pour — it's there to stop ground moisture rising through the slab.

A simple slab in cross-section: compacted substrate, taped vapour barrier turned up at the edges, mesh sitting on bar chairs with cover all round, and braced edge boards set to the finished level.

3

Place and tie reinforcement

Steel only works if it sits in the right place inside the concrete.

Handle and cut reinforcing components safely. Mesh and bar have sharp cut ends — wear gloves and eye protection, use bolt cutters or a grinder correctly, and cap or bend down any exposed bar ends that could spike someone.
Position bars and mesh to the drawings. Lap sheets of mesh as specified (typically at least two squares of overlap) and tie laps and bars with tie wire, twisting the ends down and away from the finished surface.
Set bar chairs and spacers so the steel sits at the specified height with the minimum cover maintained from the bottom, top and all edges. Cover is what protects the steel from rust — steel touching the ground or the forms will corrode and crack the concrete.

Remember: reinforcement resists tension. Mesh lying flat on the plastic does almost nothing — it must sit up on chairs, inside the concrete, to earn its keep.

4

Place concrete

Place, screed, finish — steady and methodical.

Clean out before you pour. Remove sawdust, offcuts, loose soil, leaves and ponded water from the formwork or excavation — anything left behind becomes a weak spot in the slab.
Transport concrete by wheelbarrow safely: don't overfill, keep the load balanced, run on planks over soft or reinforced areas, and keep barrow routes clear and planned in advance.
Place concrete to the specified depth, working along the form rather than dumping in one spot and dragging it — dragging separates the stone from the paste (segregation). Compact as you go so there are no voids or honeycombing, especially against edges.
Screed to the alignment of the formwork and the specified datums. Ride a straightedge across the edge boards with a sawing side-to-side motion, cutting off high spots and filling hollows, so the surface matches the designed level and falls.
Finish the surface to specification. Float first to close and flatten the surface, then apply the specified finish — wood float, steel trowel, machine trowel or broom — and run edging and jointing tools where the drawings call for them. Cure afterwards as directed.

5

Strip simple formwork

Take the mould off without damaging the concrete — or the timber.

Strip only when directed — the concrete must have gained enough strength to hold its edges. Ease the forms off; don't lever hard against green concrete.
Denail timber components immediately after stripping. A board with nails sticking up is a serious foot-injury hazard — pull or flatten every nail before the timber leaves your hands.
Clean and stack components — scrape off concrete while it's soft, then stack and store timber for reuse, or bundle it neatly for removal if it's finished with.
Remove formwork components from site (or to their storage point) so the finished work area is left clear and safe.

6

Clean up

The job isn't done until the site and the tools are squared away.

Clean up to legislative and workplace requirements for safety, waste disposal, materials handling and environmental protection. Sort and dispose of waste correctly — timber, steel offcuts, plastic and general waste each go where the site rules say.
Concrete slurry never goes into stormwater drains or waterways. Wash tools and barrows into the designated washout area only — cement washwater is alkaline and harmful to the environment.
Check, maintain and store tools and equipment — wash them before the concrete sets, dry and store them properly, and report any faults found during the job so gear is right for next time.

★

Know this cold

The knowledge behind the skill — expect to be asked about all of it.

Rules and quality

The NCC and relevant Australian Standards set the compliance requirements for simple concreting — depths, reinforcement cover, falls and tolerances all trace back to them via the job's drawings and specifications.
Workplace quality policies apply too: correct dimensions and levels, cover maintained, the specified finish achieved, and proper curing — checked against the plans, not memory.

Safety essentials

Wet concrete is caustic — it burns skin on prolonged contact. Waterproof gloves and boots, wash splashes off promptly.
Cutting concrete products dry releases silica dust — use water suppression or extraction and the required respiratory protection.
Manual handling (barrows, mesh, bags of cement), underground services, exposed bar ends, and public protection with signage and barricades are the everyday risks of this work.

Tools, equipment and materials

Tools: shovels, rakes, wheelbarrow, screed board (straightedge), wood and magnesium floats, steel trowel, trowelling machine, edger, jointer, broom, spirit level, stringline, tape, hammer, saw, bolt cutters, concrete vibrator.
Materials and their jobs: edge forms and boards shape the pour; pegs hold them to line; bracing stops them spreading; fabric sheet mesh and reinforcing bars carry tension; bar chairs and spacers hold steel at the right height with cover; vapour barriers stop rising moisture.

Simple forms you'll pour

Pathways, simple slabs and aprons, garden edges, channels, post holes, and beam thickeners (deepened strips within a slab that act as stiffening beams).

Concrete itself

Ingredients: cement, sand (fine aggregate), coarse aggregate and water, in controlled proportions. The water-to-cement ratio drives strength — more water means weaker concrete.
Strength grades (e.g. 20 MPa, 25 MPa, 32 MPa) suit different uses — lower strengths for paths and edges, higher for driveways and structural work. Use what's specified.
Maintain design strength during placement: never add water on site to make it easier to work, don't drag or drop concrete so it segregates, and place it within its workable time.
Mixing: pre-mixed delivery for volume; site or barrow mixing for small jobs — measured proportions, mixed until uniform.
Curing: keep the concrete moist and protected for around seven days (water sprays, covering, curing compound). Concrete gains strength by hydration — drying out too early leaves it weak and dusty.
Vibrating compacts concrete and removes air, but over-vibration makes the stone sink and paste rise — segregation and a weak surface. Vibrate until air bubbles stop, then move on.

Levelling and setting out

Work from datums given on the drawings; transfer levels with a spirit level, stringlines or a laser/optical level; set the form tops to the finished surface height so screeding off the forms gives the designed level and falls automatically.

Calculating concrete volume

Volume = length × width × depth, all in metres, giving cubic metres (m³). Example: a path 6.0 m long × 1.2 m wide × 0.1 m deep = 0.72 m³. Add around 10% for wastage and uneven substrate — order about 0.8 m³.

Finishes at a glance

Finish	How it's done	Where it's used
Wood-floated	Wood or magnesium float worked over the screeded surface	General flat work; slightly gritty, even texture with good grip
Trowelled	Steel trowel after bleed water has gone, in passes	Smooth, dense, hard surface — internal slabs and covered areas
Machine trowel	Powered trowelling machine (helicopter) on larger areas	Big slabs where a hand trowel would be too slow
Broomed	Broom dragged across the surface after floating	Paths, driveways, ramps — slip resistance outdoors

Storage and waste

Store cement dry, off the ground and covered; keep mesh and bar clean and off the dirt; stack formwork timber flat for reuse. Manage waste in an environmentally friendly way — reuse, recycle steel and clean timber, contain slurry, and dispose of the rest per site rules.

!

Where people slip up

Common mistakes — and what to do instead.

"It's a bit stiff — chuck some water in." Correction: adding water on site raises the water-cement ratio and cuts the design strength — the concrete no longer meets its grade. Order the right slump for the job and never water up without proper authorisation.

Mesh lying flat on the vapour barrier, or "hooked up" with a rake mid-pour. Correction: steel at the bottom of the slab (or dragged up unevenly) can't do its job and will rust without cover. Set bar chairs at the correct height before the pour, walk on planks or between sheets, and check cover as you place.

Vapour barrier with holes, or laps just butted together. Correction: a punctured or poorly lapped barrier lets ground moisture rise straight through the slab. Lap joins around 200 mm, tape them, turn the plastic up at the edges, and patch every puncture before concrete goes down.

Trowelling while bleed water is still sitting on the surface. Correction: working bleed water back in creates a weak, dusty surface that flakes later. Screed, bull-float, then wait for the bleed water to evaporate before floating and trowelling.

Hosing tools and barrows out over the nearest stormwater drain. Correction: cement slurry is highly alkaline and harms waterways — it's an environmental breach. Wash out only in the designated, contained washout area, every time.

Aa

Mini-glossary

The words of the trade for this unit.

Aggregate: The sand (fine) and crushed stone or gravel (coarse) that make up most of a concrete mix.
Bar chair: A plastic or wire support that holds reinforcing mesh or bars at the correct height inside the slab so cover is maintained.
Beam thickener: A deepened strip of concrete within a slab, formed by trenching the substrate, that acts as a stiffening beam.
Bleed water: Water that rises to the surface of freshly placed concrete as the solids settle. Let it evaporate before finishing.
Cover: The specified minimum thickness of concrete between the reinforcement and any surface or edge — it protects the steel from corrosion.
Curing: Keeping concrete moist and protected after finishing (typically about seven days) so it hydrates fully and reaches its design strength.
Datum: A fixed reference level shown on the drawings from which finished heights and falls are measured.
Formwork: The temporary mould — edge boards, pegs and bracing — that holds wet concrete to the required shape and level until it sets.
Lap: The specified overlap where two sheets of mesh or lengths of bar meet, tied so they act as one piece of steel.
Screed: To strike off wet concrete level with the form tops using a straightedge worked with a sawing motion; also the board itself.
Segregation: Separation of coarse aggregate from the cement paste — caused by dragging, dropping or over-vibrating concrete — which weakens the result.
Slump: A measure of how wet and workable a concrete mix is. Specified when ordering; higher slump means wetter concrete.
SWMS: Safe Work Method Statement — the site document describing a high-risk task's hazards and the controls everyone must follow.
Vapour barrier: Heavy plastic sheeting laid under a slab, lapped and taped, to stop moisture rising from the ground through the concrete.