Envelope
Wall underlay and cavity systems
Install wall underlay, rigid air barriers where specified, tapes, cavity battens, flashings, and drainage/ventilation paths before cladding.
How to execute this stage
Micro-stage control plan
Work through each applicable step in order. A hold point means pause the dependent decision or work until the stated evidence and authorised review are complete.
01Check wall underlay laps, damage, taping, penetrations, window openings, cavity batten layout, fixings, and drainage pathsLevel 2 · Envelope
TaskCheckHold pointEvidenceRecordNext actionSimple explanation
Check wall underlay laps, damage, taping, penetrations, window openings, cavity batten layout, fixings, and drainage paths.
Technical context
Coordinate this work against Wall sections, E2/AS1 where applicable, the current consent status, and the actual site condition. Confirm interfaces before releasing dependent work.
Why it matters: The main recorded risk is: Water entry. A missed check can create rework, delay, hidden defects, an inspection failure, or a departure from approved project documents.
Prerequisites
- Wall sections is current, approved for the intended use, and available to the people doing the work.
- E2/AS1 where applicable and relevant product information have been checked.
- Access, responsibility, safety controls, preceding work and the wrap/cavity inspection sequence are confirmed.
Checks
- Check the completed work against Wall sections and E2/AS1 where applicable.
- Check specifically for: Water entry.
- Avoid this known mistake: Cladding over torn wrap.
Evidence to save
- Wide, location-identifying and close-up photographs of the completed wall underlay and cavity systems work before it is concealed.
- Marked-up Wall sections or a precise drawing/detail reference.
- Wrap/cavity inspection result, consultant record, trade QA record or written not-applicable reason.
Hold point
Do not cover, backfill, load, connect, certify or release the next activity until Wrap/cavity inspection and the required project evidence are complete or the authorised reviewer confirms what may proceed.
Stop or escalate when
- Water entry
- Cladding over torn wrap
- The current drawing, approval, competent reviewer or required evidence cannot be confirmed.
Documents and records
- Wall sections
- E2/AS1 where applicable
- Current RFI/site-instruction/change record
- Inspection and evidence register
- Cost effect
- Rectification, reinspection, delay, damaged follow-on work, access loss and changed scope can increase the cost of wall underlay and cavity systems. Record the cause and obtain written pricing before approving a commercial change.
- Programme effect
- This activity controls the release of dependent work. Update the lookahead programme and notify affected trades if the hold point, information, inspection or evidence is not ready.
Next action
Confirm cavity system matches the cladding and E2/manufacturer requirements for the specific wall build-up.
Applicability: Apply when this work package is included in the current project scope. Confirm project-specific consent, contract, design, site and authority requirements.
Use the current consented/issued project documents and competent site review. BuildPath does not approve work.
02Confirm cavity system matches the cladding and E2/manufacturer requirements for the specific wall build-upLevel 2 · Envelope
TaskCheckHold pointEvidenceRecordNext actionSimple explanation
Confirm cavity system matches the cladding and E2/manufacturer requirements for the specific wall build-up.
Technical context
Coordinate this work against E2 details, Cladding manufacturer instructions, the current consent status, and the actual site condition. Confirm interfaces before releasing dependent work.
Why it matters: The main recorded risk is: Blocked cavity. A missed check can create rework, delay, hidden defects, an inspection failure, or a departure from approved project documents.
Prerequisites
- E2 details is current, approved for the intended use, and available to the people doing the work.
- Cladding manufacturer instructions and relevant product information have been checked.
- Access, responsibility, safety controls, preceding work and the pre-cladding inspection sequence are confirmed.
Checks
- Check the completed work against E2 details and Cladding manufacturer instructions.
- Check specifically for: Blocked cavity.
- Avoid this known mistake: Battens missing at junctions.
Evidence to save
- Wide, location-identifying and close-up photographs of the completed wall underlay and cavity systems work before it is concealed.
- Marked-up E2 details or a precise drawing/detail reference.
- Pre-cladding inspection result, consultant record, trade QA record or written not-applicable reason.
Hold point
Do not cover, backfill, load, connect, certify or release the next activity until Pre-cladding inspection and the required project evidence are complete or the authorised reviewer confirms what may proceed.
Stop or escalate when
- Blocked cavity
- Battens missing at junctions
- The current drawing, approval, competent reviewer or required evidence cannot be confirmed.
Documents and records
- E2 details
- Cladding manufacturer instructions
- Current RFI/site-instruction/change record
- Inspection and evidence register
- Cost effect
- Rectification, reinspection, delay, damaged follow-on work, access loss and changed scope can increase the cost of wall underlay and cavity systems. Record the cause and obtain written pricing before approving a commercial change.
- Programme effect
- This activity controls the release of dependent work. Update the lookahead programme and notify affected trades if the hold point, information, inspection or evidence is not ready.
Next action
Photograph the cavity system before cladding hides it.
Applicability: Apply when this work package is included in the current project scope. Confirm project-specific consent, contract, design, site and authority requirements.
Use the current consented/issued project documents and competent site review. BuildPath does not approve work.
03Photograph the cavity system before cladding hides itLevel 2 · Envelope
TaskCheckHold pointEvidenceRecordNext actionSimple explanation
Photograph the cavity system before cladding hides it.
Technical context
Coordinate this work against Window/door details, Underlay/air barrier specification, the current consent status, and the actual site condition. Confirm interfaces before releasing dependent work.
Why it matters: The main recorded risk is: Damaged underlay. A missed check can create rework, delay, hidden defects, an inspection failure, or a departure from approved project documents.
Prerequisites
- Window/door details is current, approved for the intended use, and available to the people doing the work.
- Underlay/air barrier specification and relevant product information have been checked.
- Access, responsibility, safety controls, preceding work and the council inspection if listed sequence are confirmed.
Checks
- Check the completed work against Window/door details and Underlay/air barrier specification.
- Check specifically for: Damaged underlay.
- Avoid this known mistake: No cavity closer.
Evidence to save
- Wide, location-identifying and close-up photographs of the completed wall underlay and cavity systems work before it is concealed.
- Marked-up Window/door details or a precise drawing/detail reference.
- Council inspection if listed result, consultant record, trade QA record or written not-applicable reason.
Hold point
Do not cover, backfill, load, connect, certify or release the next activity until Council inspection if listed and the required project evidence are complete or the authorised reviewer confirms what may proceed.
Stop or escalate when
- Damaged underlay
- No cavity closer
- The current drawing, approval, competent reviewer or required evidence cannot be confirmed.
Documents and records
- Window/door details
- Underlay/air barrier specification
- Current RFI/site-instruction/change record
- Inspection and evidence register
- Cost effect
- Rectification, reinspection, delay, damaged follow-on work, access loss and changed scope can increase the cost of wall underlay and cavity systems. Record the cause and obtain written pricing before approving a commercial change.
- Programme effect
- This activity controls the release of dependent work. Update the lookahead programme and notify affected trades if the hold point, information, inspection or evidence is not ready.
Next action
Close the wall underlay and cavity systems stage, link its evidence, resolve outstanding defects and release only the next applicable stage.
Applicability: Apply when this work package is included in the current project scope. Confirm project-specific consent, contract, design, site and authority requirements.
Use the current consented/issued project documents and competent site review. BuildPath does not approve work.
Trade-to-trade control
Interfaces and release gates
Use the actual consented design, specification and authorised reviewers. These controls help expose gaps; they do not approve work.
Roof framing, roofing and wall envelope
Prerequisites
- • Roof geometry, falls, drainage points and penetrations are coordinated
- • Underlay/cavity/cladding/roof systems and compatible accessories are approved
- • Temporary weather protection and material storage are effective
Interface checks
- • Roof-to-wall, parapet, apron, saddle and penetration junctions follow current details
- • Drainage capacity, overflow path and discharge points are unobstructed
- • Sequencing does not trap water or leave underlay, framing or insulation exposed
Evidence before release
- • Wide and close-up junction photographs
- • Product/system installation checklist
- • Designer/roofing/cladding review where the consent or contract requires it
Next team: Cladding, window and interior teams
Open the related Workspace control →Windows, underlay, cavity, flashings and cladding
Prerequisites
- • Opening dimensions and tolerances are checked before delivery
- • Window/cladding/underlay details are coordinated at sill, jamb, head and corners
- • Cavity closures, tapes, sealants and flashings are system-compatible
Interface checks
- • Drainage/ventilation paths remain open and shingle laps shed water outward
- • Fixings, packers, air seals and required clearances match the approved details
- • Adjacent decks, paving, roofs and landscaping preserve threshold and cladding clearances
Evidence before release
- • Opening pre-installation check
- • Sill/jamb/head sequence photographs
- • Window/cladding installer QA and any required observation record
Next team: Interior lining, sealant and exterior works teams
Open the related Workspace control →What happens in this stage
- Check wall underlay laps, damage, taping, penetrations, window openings, cavity batten layout, fixings, and drainage paths.
- Confirm cavity system matches the cladding and E2/manufacturer requirements for the specific wall build-up.
- Photograph the cavity system before cladding hides it.
Before work starts
- Confirm the latest issued-for-construction and consented documents for wall underlay and cavity systems are on site, including Wall sections.
- Check E2/AS1 where applicable, approved product data, RFIs, minor variations, and amendment status before work starts.
- Confirm the subcontractor understands the scope, hold points, access, protection requirements, H&S controls, and quality evidence required.
- Check the programme sequence so this stage does not start before earlier work, inspections, testing, or concealed-work photos are complete.
- Confirm materials delivered to site match the specification, are dry/undamaged, and are stored according to manufacturer instructions.
During the work
- Walk the work face early, mid-shift, and before close-up. Compare actual work with the consented drawings, specification, and manufacturer details.
- Check set-out, levels, falls, clearances, penetrations, fixings, bracing, waterproofing, or protection points that will be difficult to see later.
- Ask trades to show their own quality checks rather than only saying the work is complete.
- Keep weather, site condition, delivery, delay, inspection, RFI, variation, and safety notes in the daily report.
- Photograph any work before it is covered, backfilled, lined, clad, tiled, painted, or otherwise hidden.
After the work
- Complete a close-out walk with the subcontractor and mark defects immediately while access is still available.
- Confirm required inspection bookings, council results, producer statements, LBP Records of Work, warranties, test certificates, or installer declarations are obtained.
- Update as-built notes where service routes, drainage, fixings, penetrations, or dimensions differ from the design.
- Confirm the area is protected from weather, other trades, impact damage, contamination, or premature loading.
- Update the lookahead programme and tell affected trades what is ready, what is blocked, and what must not be covered.
Common problems and step-by-step solutions
Wall underlay damage
- 1Stop the affected wall underlay and cavity systems activity if continuing could hide defective work, create unsafe work, or move away from the consented design.
- 2Photograph the condition from wide, medium, and close-up angles. Include a tape, level, datum mark, gridline, or drawing reference where useful.
- 3Check the latest consented architectural, structural, civil, services, and specification documents before giving an instruction.
- 4Ask the subcontractor to explain the cause, proposed fix, timing impact, and whether the fix changes consented work.
- 5Escalate to the builder/project manager, designer, engineer, council inspector, or client when the fix affects structure, weathertightness, drainage, H1, fire/safety, cost, programme, or consent.
- 6Record the decision, responsible person, drawing/RFI/variation reference, photos, and follow-up inspection in the daily report.
Cavity batten problem
- 1Stop the affected wall underlay and cavity systems activity if continuing could hide defective work, create unsafe work, or move away from the consented design.
- 2Photograph the condition from wide, medium, and close-up angles. Include a tape, level, datum mark, gridline, or drawing reference where useful.
- 3Check the latest consented architectural, structural, civil, services, and specification documents before giving an instruction.
- 4Ask the subcontractor to explain the cause, proposed fix, timing impact, and whether the fix changes consented work.
- 5Escalate to the builder/project manager, designer, engineer, council inspector, or client when the fix affects structure, weathertightness, drainage, H1, fire/safety, cost, programme, or consent.
- 6Record the decision, responsible person, drawing/RFI/variation reference, photos, and follow-up inspection in the daily report.
Failed wrap/cavity inspection
- 1Stop the affected wall underlay and cavity systems activity if continuing could hide defective work, create unsafe work, or move away from the consented design.
- 2Photograph the condition from wide, medium, and close-up angles. Include a tape, level, datum mark, gridline, or drawing reference where useful.
- 3Check the latest consented architectural, structural, civil, services, and specification documents before giving an instruction.
- 4Ask the subcontractor to explain the cause, proposed fix, timing impact, and whether the fix changes consented work.
- 5Escalate to the builder/project manager, designer, engineer, council inspector, or client when the fix affects structure, weathertightness, drainage, H1, fire/safety, cost, programme, or consent.
- 6Record the decision, responsible person, drawing/RFI/variation reference, photos, and follow-up inspection in the daily report.
Verification
Source / where to check
Use current official information and the controlled documents for the actual project.
Check E2/AS1, consented wall/roof details, cladding specifications, flashing details, and manufacturer installation requirements.
Use the exact current installation manual, warranty requirements, BRANZ/Appraisal information where applicable, and product data sheet for the product on site.
MBIE guidance explains that work should be built to the issued building consent, inspections must be managed, and records/certificates should be kept for CCC.
The issued consent drawings, stamped specifications, engineering drawings, RFIs, minor variations, and amendments control the specific project.
Use the exact current installation manual, warranty requirements, BRANZ/Appraisal information where applicable, and product data sheet for the product on site.
Insufficient data to verify — confirm against the current consented drawings, specifications, Auckland Council requirements, Auckland Unitary Plan, NZ Building Code, relevant NZ Standard, consultant advice, manufacturer instructions, insurance broker, insurer, lender, lawyer, accountant or project contract.
Project-specific consented documents and professional advice override generic guidance.
Common inspections required
- Wrap/cavity inspection
- Pre-cladding inspection
- Council inspection if listed
Common risks
- Water entry
- Blocked cavity
- Damaged underlay
- Incorrect lap direction
- Non-compliant substitution
Common mistakes
- Cladding over torn wrap
- Battens missing at junctions
- No cavity closer
- Incorrect tape at openings
Required documentation
- Latest consented drawings and specifications
- Relevant RFIs, site instructions, amendments, minor variations, and variation approvals
- Subcontractor scope, QA checklist, delivery dockets, product data, and installation records
- Inspection booking/result records and photos before cover-up
- Daily site report notes covering labour, weather, progress, delays, risks, and decisions
Photos or diagrams needed
- Wide photo showing where wall underlay and cavity systems is happening on the site
- Close-up photos of critical details, fixings, laps, seals, penetrations, clearances, levels, or falls
- Photo of product labels, batch numbers, delivery dockets, and installer marks where relevant
- Marked-up drawing or simple diagram showing any changed location, clash, defect, or agreed remedial detail
Construction manager checklist
- 1Scope, drawings, specification, product data, and latest revision confirmed
- 2Trade briefed on hold points, tolerances to verify, evidence required, and inspection sequence
- 3Access, storage, protection, temporary works, and safety controls in place
- 4Work checked against drawings during installation, not only at completion
- 5Photos and records captured before work is concealed
- 6Defects, RFIs, delays, and variations recorded with owner and due date
- 7Inspection/producer statement/warranty/Record of Work requirements tracked for CCC
Questions to ask the subcontractor
- Which drawing, detail, or manufacturer instruction are you working from?
- What needs to be checked before this is covered or handed to the next trade?
- What could stop you today: weather, access, materials, information, inspections, or other trades?
- Does anything on site differ from the drawings or specification?
- What evidence will you provide for the quality file and CCC file?
Red flags to stop work
- Work differs from consented drawings or specification and no approved variation/RFI exists
- A structural, weathertightness, waterproofing, drainage, fire/safety, or H1 detail is unclear
- The trade wants to cover work before inspection, testing, or photos are complete
- Specified materials are missing, substituted, damaged, wet, expired, or installed outside manufacturer instructions
- A safety control is missing for excavation, heights, plant movement, electrical work, asbestos, silica, or public protection
What to record in the daily report
- Exact location and quantity of work completed
- Trade headcount, company names, plant used, deliveries, and material batch/product details
- Weather, site conditions, delays, instructions received, RFIs raised, and inspections booked/passed/failed
- Photos taken before cover-up and any defects or non-conformances found
- Next-day lookahead, blockers, and who is responsible for each action
Use this in my project
Turn wall underlay and cavity systems into controlled action
Open the relevant workspace register, create the project-specific record, link the controlling documents and preserve evidence. The guide does not automatically approve or verify the action.