Building and Structural Construction N4 — Comprehensive Notes

General Aims

Provide learners with the knowledge & practical skills required for structural design and construction activities in industry.
Integrate theoretical understanding with workshop-based, technical and simulated practical exposure.

Specific Aims

Develop a thorough background in Building & Structural Construction theory, methodology and technological applications.
Enable students to apply technological principles to real-world building scenarios.

Prerequisites (any ONE)

N3 certificate including Building & Civil Technology + an N2 trade subject (Plumbing Theory / Carpentry / Bricklaying & Plastering Theory).
Grade 12 pass with Mathematics or Physical Science.
NCV Level 4 Certificate in Civil & Building Construction.
Technical Matric with technical subjects.
Senior Certificate for adult learners at NQF 4 with ≥ 50 % in Mathematics or Physical Science.

Duration

Full-time contact: 7.5 h/week (part-time offering possible).

Evaluation & Promotion Mark

Continuous Assessment (ICASS): 2 formal college tests.
Eligibility: ≥ 40 % ICASS to sit final exam.
Final exam (Report 191): 4 h • 100 marks • Closed book (A2 drawing paper + BOE 8/2 steel tables supplied).
Weighting categories:
• Knowledge & Understanding: 5 – 10 %
• Application: 10 – 80 %
• Analysis/Synthesis/Evaluation: 5 – 20 %
Promotion mark calculation:
$\text{Promotion Mark}=0.40\,(\text{ICASS})+0.60\,(\text{Exam})$
Pass requirement: ≥ 40 % on final exam and overall promotion mark.

Mark Allocation per Module

Foundations 10 % | Damp-proofing 10 % | Bonds in brickwork 10 % | Arches 10 % | Steel door frames & windows 10 % | Roofs 15 % | Roof coverings 5 % | Guttering 5 % | Ceilings 5 % | Structural steelwork 20 %

Work Schedule (suggested contact hours)

Foundations – 10 h
Damp-proofing – 10 h
Bonds in Brickwork – 10 h
Arches – 10 h
Steel Door Frames & Windows – 10 h
6-7. Roofs – 15 h
Roof Coverings – 5 h
Guttering – 5 h
Ceilings – 5 h
9-10. Structural Steelwork – 20 h (= 100 h total)

Lesson-Plan Template (highlights)

Weekly page: outcomes • in-class examples • facilitation method (lecture / group work / demo / simulation) • teaching aids • student tasks • recap section.
Photocopiable for Weeks 1-10.

Module 1 — Foundations

Outcomes

Analyse soil samples (clay, loam, loose/sandy) to select foundation type.
Identify & sketch strip, stepped, raft, pad & pile foundations.
Explain concrete strengths, mix proportions & curing per regulations for single- & double-storey buildings.

Key Concepts & Details

Soil compaction = application of dynamic energy to reduce void ratio & increase density.
Common compaction plant: rollers, plate compactors.
Bearing capacity hierarchy: rock > dense sand > loam > clay > loose sand.

Concrete / Mortar Mix Calculations (exercise recap)

Dry volume factor ≈ 1.33 × wet volume.
Example: 1 m³ mortar, mix $1:4$ (cement : sand)
• Dry volume $=1.0\,\text{m}^3\times1.33=1.33\,\text{m}^3$
• Cement $=\frac{1.33\times1}{1+4}=0.266\,\text{m}^3$
• Weight $=0.266\,\text{m}^3\times1440\,\text{kg/m}^3=383.04\,\text{kg}\approx7.66\text{ bags}$
• Sand volume $=0.266\times4=1.064\,\text{m}^3$
• Water (w/c 0.5) $=0.5\times383.04\,\text{kg}=191.5\,\text{L}$

Brick Quantities (snapshot)

Standard brick with mortar volume $0.20\times0.10\times0.10=0.002\,\text{m}^3$
Single-brick wall 190 mm thick, 1 m² area → $95$ bricks (+10 % wastage ≈ 105).

Real-world links

Foundation animations, soil type videos, water-cement ratio tutorials (QR codes supplied in text).

Module 2 — Damp-Proofing

Outcomes

Describe materials & application of plastic DPC/DPM, bitumen sheeting & torch-on.
Draw DPC placement below windows & in cavity walls.
Detail 30° eaves section showing insulation & ventilation.
Show DPC solutions for basements & concrete tanks.

Essentials

DPC ≠ DPM: DPC = barrier in walls; DPM = membrane under slab.
Minimum overlaps: $\ge100\,\text{mm}$ at joints; lap DPC onto DPM $\ge50\,\text{mm}$ .
Vertical clearance: top of DPC ≥ $150\,\text{mm}$ above finished ground.
Basement waterproofing: multi-coat bitumen, cavity drain membranes or integral tanking.

Ventilation Example

Roof whirlybird: wind-driven turbine in galvanized/aluminium; sealed Teflon bearings; aerofoil vanes shed rain.

Module 3 — Bonds in Brickwork

Outcomes

Identify & draft English, Stretcher & Flemish bonds in right-angle, T- & cross-junctions (1 & 1.5-brick walls).
Adapt bonds to acute/obtuse angles.

Key Points

Correct mortar class must be weaker than bricks to avoid face spalling.
Bond summaries:
• Stretcher: all stretchers, each course half-brick stagger.
• English: alternate stretcher & header courses, queen closer at quoins.
• Flemish: stretchers & headers alternate within same course.

Aggregates & Mortar Constituents (exercise)

SA sand sources: quartzitic coarse (Klipheuwel), silica fine (Philippi), river sands, mine tailings.
Coarse aggregates grouped into Igneous, Metamorphic, Sedimentary rock types.
Lime addition: ≤ 10 kg/50 kg cement (Class I) or ≤ 25 kg (Class II) to enhance workability & water retention; never with masonry cement.

Module 4 — Arches

Outcomes

Locate centring for masonry, steel & timber arches.
Draw rough/axed, segmental, half-circular (2- & 3-ring) & flat-gate arches.

Fundamentals

Vocabulary: intrados (soffit), extrados, springing line, skewback, keystone.
Structural behaviour: loads transferred as compressive thrusts to abutments & piers.
Modern applications: lintels, bridge arches (Storms River, Bloukrans), double-curved arch dams (Katse Dam).

Module 5 — Steel Door Frames & Windows

Outcomes

Detail setting of steel door & window frames in 1-brick & cavity walls.
Section top/bottom of domestic & industrial steel casements.
List glass types & characteristics.

Highlights

Steel doors: durable, secure, often fire-rated (≥ 1.5 h), galvanised; require paint maintenance.
Alternative frame materials: wood, aluminium, PVC, precast concrete.
Glass catalogue:
• Safety (tempered) – shatters into small particles.
• Laminated – bonded layers, UV filtering, energy efficient.
• Annealed – standard cooled glass, stronger than float.
• Double-glazed – two panes + spacer for insulation (cold climates).

Module 6 — Roofs

Outcomes

Sketch Howe, Mono-pitch, Pratt (pitched & bridge), Camelback, Saw-tooth, Fan trusses; Lean-to variants.
Show timber/steel truss connections: bolted, nailed, gang-nail.
Describe riveted/bolted Fink, Monitor & Saw-tooth trusses.
Draw pitch & valley sections for steel trusses.

Truss Identification

Saw-tooth: series of mono-pitches admitting light for factories.
Camelback: polygonal top chord (3-5 slopes) for long spans.
Fan: subdivided top chord; economical on timber lengths.

Connection Examples

Gang-nail plates: pressed steel connector plates, factory-assembled.
Bolted joints: $Ø12–20\,\text{mm}$ bolts through plates/webs; washers essential.
Nailed: site-assembled, depends on nail pattern & splice plates.

Force Analysis

Resolve inclined loads into vertical & horizontal; calculate reactions; determine axial forces (T/C) with $\sum F<em>x=0$ , $\sum F</em>y=0$ , $\sum M=0$ .

Module 7 — Roof Coverings

Outcomes

Label fixing methods for concrete/clay tiles, corrugated & IBR sheeting, long-span aluminium, step tiles on both timber & steel purlins.
Discuss waterproofing & torch-on membranes.

Area Formulae (rapid take-off)

Hip (rectangular): $\frac{(C+L)\,A}{2}$
Gable: $2\,A\,L$
Lean-to: $A\,L$
Mansard: $\frac{A\,L\,C}{2}$

Sealant Types

Acrylic, polyurethane, silicone, liquid rubber, butyl/bituminous tapes.
Solvent-based = high resilience; water-based = low odour & cheaper but less durable.

Torch-On (bituminous membrane)

Apply primer on clean substrate → align 3-ply roll → heat lower bitumen to bond → roll & press → overlap $\ge75\,\text{mm}$ side, $\ge100\,\text{mm}$ end.
Lifespan 15–20 yr; monitor brittleness & UV degradation.

Module 8 — Guttering

Outcomes

Draw half-round, square & box gutters with downpipes in galvanised steel, fibre-cement & plastic.

Key Facts

Functions: divert rainwater away from entrances, protect walls/foundations, facilitate harvesting.
Box gutter detailing: fall 1:200 to outlets; provide expansion joints; line with torch-on or EPDM.
Downpipe sizing rule of thumb: $\approx10\,\text{cm}^2$ pipe area per $1\,\text{m}^2$ roof plan area (regional rainfall dependent).

Module 9 — Ceilings

Outcomes

Identify gypsum/rhino board, fibre board, fibre-cement, tongue-&-groove timber, acoustic tiles & pressed-steel suspended ceilings.
Draft suspended ceiling construction on aluminium grid.

Technical Notes

Ceiling area ≈ floor area; failure can cause severe injury (case studies of mall collapses).
Fire considerations: SANS 10400 part T; specify fire-rated boards or mineral fibre where required.
Suspension grid: main tees at 1200 mm, cross tees at 600 mm; hanger wires @ 1200 mm max spacing, min wire dia $\phi3.5\,\text{mm}$ .

Module 10 — Structural Steelwork

Outcomes

Draw rivet types, welding symbols, hex bolt & nut.
Distinguish beam vs column sections.
Show angle iron, gusset plate, holding-down bolt.
Detail column-to-beam & beam-to-beam right-angle connections (plans, elevations, side views).
Draft column with base plate on concrete footing.
Produce isometric of base plate, gussets, angles, stanchion & beam.

Steel Profiles & Symbols

Beams: UB/I-sections; Columns: UC/H-sections (thicker web & flanges).
Welding symbols per ISO 2553: fillet $\small\triangle$ , butt $\small\perp$ ; arrow/other side convention.
Rivets: snap, countersunk, pan-head; specify dia, pitch, edge distance $\ge2d$ .

Base Plate Design (simplified)

Axial load $P$ & moment $M$ → bearing pressure $q_{max}=\frac{P}{A}+\frac{6M}{B\,L^2}$ (rectangular plate).
HD bolts typically $M20$ or $M24$ , 4 off, grouted pocket, 50 – 75 mm projection for nut/washer.

Glossary Highlights (selected)

Abutment: end support of arch; carries thrust.
Bitumen: petroleum-based waterproofing substance.
Brandering: timber/metal battens fixed to trusses to carry ceiling boards.
Dagha: site term for mortar.
Gang-nail plate: pressed-steel connector for factory-made timber trusses.
Keystone: highest, central voussoir in an arch.
Plumb: perfectly vertical; opposite of level.
Spalling: flaking of masonry surfaces due to moisture & freeze-thaw cycles.

Ethical / Practical Considerations

Correct choice of mortar & DPC prevents future health hazards (mould) & structural decay.
Accurate estimation of materials limits waste, reducing environmental impact & cost.
Fire-rated elements (doors, ceilings) provide critical life-safety egress time.

Real-World & Cross-Lecture Connections

Foundation design links to Soil Mechanics (N4 Civil) & Surveying (setting-out levels).
Structural steel detailing corresponds with Mechanical Draughting symbol standards.
Roof truss force analysis echoes Statics & Strength of Materials modules.
Waterproofing integrates Chemistry of bituminous products & Occupational Safety (torch-on hot works).

Quick-Reference Formula Sheet (no sheet allowed in exam — memorise!)

Promotion Mark: $0.4\,ICASS + 0.6\,Exam$
Dry Volume of Mortar: $1.33\times \text{Wet Volume}$
Brick Quantity: N=\frac{\text{Wall Volume}}{\text{Brick + mortar volume}} \times (1+\text{wastage %})
Roof Area (gable): $A_{roof}=2\,A\,L$
Box Gutter Fall: $\text{Fall}=\frac{\text{Length}}{200}$
Column Base Plate Pressure: $q_{max}=\frac{P}{A}+\frac{6M}{BL^2}$

Memorise standard masonry sizes, truss names & connection symbols — frequently tested in 4 h final exam.