A two-storey coastal house closed in without a cavity or head flashings

All three are non-compliant, but they fail in different ways and the ranking depends on what you are measuring.

• Direct-fixed cladding, no cavity, no eaves, two storeys, high wind zone, coastal. E2/AS1 uses a risk matrix that scores wind zone, number of storeys, eaves width and envelope complexity. This building scores heavily on every factor. Without a cavity, water that gets behind the sheet - at fixings, joints, cracked sealant or at the head - has no drainage path and no air space to dry into. The building paper is the only line of defence and it is punctured by every fixing. In a high wind zone, pressure differences drive wind-driven rain inward. This is the classic leaky-building combination and it is systemic, not local.
• No head flashing. This is the single most certain leak point on the elevation. Water running down the sheet above concentrates at the window head, runs behind the cladding and into the framing. Sealant over a butt joint is a maintenance item with a service life measured in a few years; the flashing is the primary defence. Highest probability of failure, limited area.
• H1.1 framing in an external wall. H1.1 is for dry interior use. External wall framing must be H1.2 because it can get wet during construction and in service. B2 requires 50 years' durability for structural elements and for weathertightness, and enclosed framing cannot be replaced without demolition. Lowest probability of immediate failure, but the most expensive to rectify and impossible to fix later.

If forced to rank by overall risk, put the cavity/no-eaves combination first because it is systemic, the head flashing second because it is the most likely to leak, and the H1.1 framing third on probability but first on irreversibility - which is why all three must be resolved before the house is closed in.

Stop installing cladding, record the current state, and get written positions before anything else is covered.

1. Photograph and measure what is already installed, and stop the cladding crew on all elevations.
2. Get the cladding manufacturer's and the designer's written position on: a cavity for this system and this wind zone; the head flashing detail; and acceptable treatment for the H1.1 framing. Copy the council - they have already failed the inspection, and their view drives the timetable.
3. Options for the cladding: (a) remove the sheets and reinstate over a drained and ventilated cavity, with proper head flashings per E2/AS1 and the manufacturer's system - expensive but the only fully compliant path; (b) ask the designer and manufacturer whether an alternative solution can be supported for this building, for example a rigid air barrier system with specific detailing, and take it to the council as a formal amendment or alternative solution - do not assume it will be accepted; (c) proceed and hope - not an option, because you will not get the inspection passed and the owner will not get a CCC.
4. For the H1.1 framing the cheapest window is now, while the walls are open: replace the external wall framing with H1.2, or obtain a specific design from the designer that addresses B2 durability and get the council to accept it. Once lined, either option costs several times more.
5. Amend the building consent for whatever changes, and have the council sign off before covering. Keep the failed inspection report, the RFIs, the designer's responses and the amended consent on file.

Acknowledge the pressure, then give the owner choices with real numbers - in writing.

• Start with what is at stake for them: an unconsented or non-compliant envelope means the pre-weathertightness inspection does not pass, no Code Compliance Certificate is issued at the end, insurers may decline cover, and a buyer's LIM will show it. Remedial work after lining is demolition-level cost. That is a much larger risk than a four to six week delay.
• Set out the options with cost and time: strip and re-clad with a cavity and flashings (most likely path); an alternative solution supported by the designer and accepted by council; and temporary weather protection while the decision is made.
• Offer the practical mitigation: shrink-wrap or a temporary roof over the frame, dehumidification, and sequencing interior work that is not behind the affected walls so the programme keeps moving. Do not line walls that will be opened up.
• Confirm the instruction in writing, including who pays for the rework: if the design or consent documentation omitted the cavity, that is a design/contract issue, not a builder's error, and it should go through a variation.
• Keep a dated record of the advice given and the owner's decision, because if they later instruct you to proceed as-is, you need to show you advised against it and that you did not simply comply.
• Never proceed on a verbal 'just get it done' - an unapproved departure from the consented plans can put your own position at risk under the Building Act as well as the owner's.