Lesson 1Compatibility and galvanic corrosion: avoiding dissimilar metals and recommended separation methodsThis lesson explains compatibility and galvanic corrosion for metal roofs in Zambia. Learn to avoid bad metal mixes, choose safe fasteners, and use separation layers, drainage, and details to protect zinc and zinc-coated steel parts.
Galvanic series and risk rankingProblematic metal combinationsNonmetallic separation layersFastener and accessory selectionDetailing to keep joints well drainedLesson 2Fasteners and clip systems: concealed clips, exposed screws, recommended materials and corrosion considerationsThis lesson covers fasteners and clips for metal roofing. It explains hidden clips, exposed screws, material choices, pull-out strength, and corrosion risks, with tips on spacing, torque, and sealing for zinc roofs in local weather.
Concealed clip types and layoutExposed screw selection and sizingStainless vs coated carbon steelFastener spacing and edge distancesAvoiding overdriving and oil canningLesson 3Roof deck and substrate requirements: steel purlins, timber battens, sheathing compatibilityThis lesson shows how roof decks and bases must hold up metal roofing. It discusses steel purlins, timber battens, and sheathing, stressing spacing, strength, fixings, and fit with zinc and zinc-coated steel sheets.
Minimum deck slopes for metal roofingSteel purlin sizing and spacing rulesTimber batten dimensions and fixingSheathing types and fastener pull-outSubstrate flatness and tolerance checksLesson 4Standing seam vs corrugated vs ribbed profiles: water tightness and thermal movementThis lesson compares standing seam, corrugated, and ribbed profiles. It looks at water tightness, wind hold, and heat expansion, helping you pick profiles, seam heights, and fixings for slope, exposure, and zinc in Zambia.
Profile selection by roof slopeStanding seam height and lock typesCorrugated and ribbed span limitsWater channeling and side lap designThermal movement in long panelsLesson 5Accessory materials: flashings, ridge caps, eaves trims, sealants compatible with zinc/zinc-coated steelThis lesson details extras like flashings, ridge caps, eaves trims, and sealants for metal roofs. It stresses leak-proof design, heat movement, and chemical fit with zinc and zinc-coated steel for Zambian builds.
Types of flashings for zinc roofsDesigning ridge and hip capsEaves trims and drip edge detailingSealant types safe for zinc surfacesThermal movement joints in accessoriesLesson 6Comparison of zinc vs zinc-coated steel: corrosion resistance, patina formation, lifespanThis lesson compares zinc and zinc-coated steel for roofing. It checks rust resistance, patina build-up, strength, cost, and life span, aiding choice for Zambian climate, details, and upkeep needs.
Base metal composition differencesPatina formation stages on zincCorrosion behavior in marine zonesCost, weight, and stiffness trade-offsTypical lifespan and warrantiesLesson 7Material properties: thickness (mm/gauge), coating weights, and expected durabilityThis lesson reviews key properties for metal roofing materials. It covers thickness in mm and gauge, coating weights, hardness, and durability, linking to span ability, dent resistance, and service life in local use.
Common zinc and steel thicknessesGauge systems and metric conversionCoating weight classes and labelsMechanical strength and span limitsService life expectations by climateLesson 8Insulation and ventilation strategy: types of insulation (rigid, mineral wool), ventilation gaps and placementThis lesson explains insulation and air flow plans under metal roofs. It covers rigid boards, mineral wool, air gaps, and vent spots to fight condensation, boost comfort, and guard zinc systems in Zambia.
Choosing rigid vs mineral woolWarm roof vs cold roof build-upsVentilation gap sizing and layoutEave and ridge vent positioningCondensation risk assessment basicsLesson 9Typical panel widths, lengths, and recommended overlaps for zinc and galvanized steelThis lesson sets standard panel widths, lengths, and overlaps for zinc and galvanised steel. It handles coil widths, expansion limits, side and end laps, and managing for leak-proof, cost-effective installs.
Standard coil and panel widthsMaximum practical panel lengthsSide lap geometry and sealant useEnd lap lengths and staggeringTransport and site handling limitsLesson 10Underlayment options: breathable membranes, vapor barriers, and synthetic underlays for temperate climatesThis lesson offers underlay choices for metal roofs in milder climates like Zambia. It compares breathable sheets, vapour blocks, and synthetics, explaining placement, overlaps, and flashing ties for moisture control.
Breathable membrane functionsVapor barrier placement rulesSynthetic underlay performanceUnderlay laps, tapes, and sealingIntegrating underlay with flashings