Load-bearing structures — primary frame works
This stage covers installation of load-bearing walls, columns, beams, slabs, rough staircases and primary steel structures. Work focuses on achieving design geometry, structural capacity and reliable joints while preventing cracks and corrosion. Key activities include formwork and shoring, reinforcement placement, concrete casting or steel erection, embedment of anchor items and interim inspections. Coordination with geotechnical, structural and MEP teams and strict control of tolerances, curing and temporary supports is common practice to reduce rework and ensure structural integrity.
Use this stage across the product
The same stage should connect the budget model, control checklist, and cost-of-error review.
Overview
The structure stage implements the primary load-bearing system defined by design documents. Typical tasks include erecting formwork and shoring, fixing reinforcement to specified cover and geometry, placing concrete of the required grade or assembling prefabricated elements, and installing embedded items and connections. Sequence and temporary works are coordinated to control deflections and load transfer during construction. Inspections and tests — reinforcement checks, concrete sampling, weld and bolt inspections — are used to confirm compliance. Attention to interface details with MEP, tolerances for finishes and corrosion protection for exposed steel reduces later remediation. Proper documentation of as-built geometry, test results and deviations supports handover and future maintenance planning.
What is included
- Formwork, shoring and temporary supports
- Reinforcement placement and fixing to specified cover
- Concrete casting or prefabricated element installation
- Erection and connection of load-bearing steel structures
- Installation of embedded plates, anchors and connection nodes
- Rough stair flights and landings
- Geometry surveys and interim inspections
Main cost drivers
- Structural complexity and non-standard geometry
- Specified concrete grade and reinforcement density
- Extent and complexity of formwork and shoring
- Use of prefabricated vs cast-in-place elements
- Site access, lifting capacity and logistics
- Extent of corrosion protection and specialised coatings
Common risks and frequent mistakes
- Incorrect geometry or out-of-tolerance elements leading to rework
- Insufficient reinforcement, wrong lap lengths or cover
- Poor concrete compaction, curing or honeycombing
- Improperly detailed or executed joints and anchors
- Missed embed positions or mislocated openings
- Inadequate corrosion protection for steel elements
Quality assurance checklist
- Verify drawings, codes and structural specifications prior to works
- Confirm geometry: levels, plumbness and dimensions against tolerances
- Check reinforcement type, spacing, laps and cover before concrete
- Verify concrete grade, placing method and curing regime
- Inspect welds, bolts and connection tolerances on steelworks
- Ensure embedment positions and anchorage are installed as shown
- Record inspection reports, test results and as-built geometry
Sub-stages
Work includes constructing load-bearing masonry or cast-in-place concrete walls and vertical enclosure elements with control of geometry and tolerances. Activities cover formwork, reinforcement where required, joint detailing and provision for openings and interfaces. Surveys and step-by-step checks ensure plumb, alignment and correct positioning of embeds. Proper curing and moisture control reduce risk of early-age cracking and ensure intended capacity.
Common issues
- Walls out of plumb or uneven surface levels
- Insufficient vertical reinforcement or poor lap details
- Incorrect location or sizing of openings and embeds
- Inadequate curing causing shrinkage cracks
Quality checks
- Verify wall alignment and level tolerances before progressing
- Confirm reinforcement layout, anchors and cover
- Check joint and opening positions against drawings
- Document curing regime and visual inspection for cracks
Columns and vertical supports are formed, reinforced and cast to carry gravitational and lateral loads. Key controls include alignment, plumbness, reinforcement cages, proper anchorage to foundations and accurate positioning of leveling plates or bolts. Temporary bracing and sequencing minimise eccentricities during casting and stripping.
Common issues
- Misaligned or leaning columns
- Poorly tied reinforcement cages leading to displacement
- Incorrect placement of anchor bolts or leveling plates
- Improper consolidation around vertical reinforcement
Quality checks
- Check column centrelines, plumbness and template positions
- Confirm reinforcement spacing, ties and cover
- Inspect anchor bolts and level plates for correct position
- Verify concrete compaction and finish at interfaces
Beams and girders form the horizontal load paths; works include formwork setup, reinforcement placement, shear and anchorage detailing and casting or installation of prefabricated members. Bracing and temporary supports control deflections during construction and transfer of loads. Attention to continuity, bearing lengths and joint detailing is common practice to avoid weak points.
Common issues
- Insufficient bearing or inadequate seat dimensions
- Inadequate anchorage of reinforcement at supports
- Formwork deflection affecting beam profile
- Poorly executed splices or joints
Quality checks
- Verify formwork alignment and support points
- Check reinforcement anchorage, hooks and laps
- Measure deflection during temporary loading where applicable
- Inspect joints, bearings and grout under seats
Interstorey slabs and floor plates are constructed by in-situ casting or by placing precast units. Controls include slab thickness, reinforcement layout, deflection limits and compaction. For multi-storey sequencing, shoring removal times and load path checks are planned to avoid progressive deformation. Curing and surface tolerance checks ensure long-term serviceability.
Common issues
- Uneven slab levels or incorrect falls
- Insufficient top or bottom reinforcement leading to cracking
- Premature shoring removal causing deflection
- Poor surface finish or delamination
Quality checks
- Confirm slab thickness and reinforcement cover before pouring
- Check temporary shoring layout and load paths
- Inspect curing regime and surface condition after stripping
- Measure levels and flatness tolerances
Rough staircases and landings are formed as part of the primary structure, providing permanent support for final finishes. Key tasks include setting riser and tread geometry, installing reinforcement and ensuring bearing conditions at supports. Temporary works control alignment and prevent settlement during concrete curing.
Common issues
- Incorrect riser/tread dimensions affecting usability
- Poor alignment of flights and landings
- Insufficient support at bearing points
- Cracking at landing-wall junctions
Quality checks
- Verify riser and tread dimensions against drawings
- Check reinforcement continuity and anchorage
- Inspect bearing supports and connections
- Confirm curing and check for visible defects
Fabrication and erection of load-bearing steelwork includes shop fabrication, surface protection, assembly, bolting and welding on site. Controls cover dimensional accuracy, weld quality, bolt pre-tensioning and corrosion protection (painting or galvanising). Lifting plans and temporary bracing are coordinated to manage loads during erection and to protect installed elements.
Common issues
- Shop fabrication tolerances not matching site conditions
- Incomplete or poor-quality welds
- Incorrect bolt grades or inadequate torque
- Insufficient corrosion protection or touch-up
Quality checks
- Review shop drawings and as-built dimensions prior to erection
- Inspect welds and bolted connections per standards
- Verify surface treatment coverage and touch-up
- Confirm alignment and plumbness after erection
This work covers installation of embed plates, anchor bolts, connection nodes and junctions between structural elements. Accurate placement and correct specification of anchor types and welding are critical to transfer loads as designed. Coordination with finish trades and services reduces clashes and ensures that embeds are protected until final finishes are applied.
Common issues
- Mislocated embeds or incorrect anchor types
- Insufficient weld or bolt capacity at connection nodes
- Clashes with MEP services or finishes
- Temporary protection of embeds missing leading to corrosion
Quality checks
- Verify embed positions with layout surveys before casting
- Check anchor type, length and installation method
- Inspect welds and bolt installation at connections
- Confirm protection of exposed embeds until handover
FAQ
Geometry is typically controlled by staged surveying, setting out from fixed reference points, and repeated checks at each construction phase. Common practice includes using templates, laser levels and plumb lines, documenting deviations, and correcting formwork or reinforcement before casting. Early detection and correction reduce need for remedial work.
Choice depends on site access, programme, quality control needs and structural design. Precast may speed erection and improve factory quality, while cast-in-place offers continuity, monolithic joints and simpler on-site connections in constrained geometries. Decision typically follows a trade-off of logistics, tolerances and coordination with other trades.
Effective measures include specifying protective coatings or galvanising, ensuring proper surface preparation, applying touch-up after site welding, and designing for drainage and ventilation. Regular inspection during and after construction and selecting compatible materials for connections are common practice to reduce long-term corrosion risk.
Because cost volatility or site-specific variables increase uncertainty.
Related glossary
Next steps
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