What options do you have to fix a Leaky Building?

Leaky Buildings – WHAT ARE THE OPTIONS?


Good information to allow proper decision-making is essential, which is normally an initial assessment followed by the necessary detailed and invasive investigation and report.  The level of detail will depend on whether legal action is being contemplated and if repair is to take place before, or after legal action is completed.

Repair Options

  • Do nothing
  • Emergency repairs
  • Targeted repairs
  • Partial reclad
  • Over cladding
  • Full reclad
  • Reclad and modify
  • Demolish and rebuild
  • Sell the building

Do Nothing

There is no obligation to repair unless the building is dangerous or insanitary.  For some, value is less important, e.g. retired owners could live in the house and leave the problem to others.  Another example is institutions with no intention to sell.

Dangerous Buildings

Under the Building Act 2004 s121, the meaning of a dangerous building is one that “is likely to cause injury or death (whether by collapse or otherwise) to any person in it or to persons on the property”.  To determine whether a building could collapse, investigation is required with testing of timber for decay and treatment or, in the case of steel framing, for corrosion, followed by analysis and opinion by a structural engineer.

Insanitary Buildings

The main health risk is that certain mould spores contain mycotoxins (chemical toxins) within their ‘shell’.  Some moulds are also allergenic, so those with allergies need to be careful.  It is often only when the building begins to dry that the mould spores become airborne and a threat to health, so investigation by removal of internal linings (which are then left off), temporary covers, or even repairs that do not remove the mould can make the problem worse.

The most frequently used test method is air sampling using a non-viable spore trap.   Owners of at-risk buildings should consider testing, especially if the building is occupied by older people, younger children, or those with immuno suppressive illnesses.

Emergency Repairs

These repairs can be undertaken, as defined in s41 of the Building Act 2004.  Such work is when a Building Consent “cannot practically be obtained in advance and the work has to be carried out urgently for the purpose of saving or protecting life or health or preventing serious damage to property”.  A building consent would still be needed before any subsequent remedial work.

Targeted Repairs

In the early days of leaky buildings, targeted repairs were the norm, however the focus shifted from not only fixing the defects, to correcting inadequate systems.  For example, direct fixed monolithic cladding over untreated (Radiata)pine framing is inherently vulnerable to failure and, in almost all cases, unlikely to meet Building Code Clauses E2 (which refers to external moisture) and B2 (durability).

So the first question is ‘what is the E2/AS1 risk score?’ (E2/AS1 is the government approved acceptable solution that is deemed to comply with the building code – in this case clause E2).  The risk score helps to determine if the building can be reclad with a direct fixed cladding, or whether a cavity required  And ‘what is the level and type of timber framing treatment?

So it is quite possible in post 2004 buildings, that have a cavity and the framing is treated, that targeted repairs due to poor details will re-emerge.

However in earlier buildings targeted repairs are still undertaken because of poor knowledge, inadequate investigation and lack of remediation experience among investigators, designers, builders and councils.

On the legal front ‘will the building repair be compliant with the building code as is required under s17 of the Building Act?’   A building consent is required for all subsequent leaky building repairs under Schedule 1 of the Building Act.   Vendor warranties within sale and purchase agreements and misguided vendor misrepresentation can result in expensive litigation.  Legal advice should be sought before suspect homes are sold.

An important consideration is the value of the building once repaired.  If targeted repairs are undertaken leaving the cladding unchanged then stigma remains and purchasers could still shy away.

If the house is reclad with a different cladding material, i.e. weatherboards, then stigma may reduce but may persist for perhaps two to three years, after which time the repair as ‘proven’ itself.

Partial Reclad

This is possible where there are localised risks and faults on some of the elevations, or there a different lower-risk claddings. However, is a house with three reclad elevations and one not repaired going create confidence among potential buyers?   In the case of a part brick-veneer and plaster-clad house, a partial reclad is often  sensible.


The surveyor needs to be confident that the underlying wall framing, whether it is steel or timber, is durable and is not unduly damaged.  There is also the issue of mould. So whilst over-cladding, from a weathertightness point may seem satisfactory, it can leave an unpleasant legacy that is difficult and expensive to rectify.

And what is the cost saving of not removing the cladding against the risks of leaving it in place in the overall scheme of things?

Full Reclad

The default option for monolithic cladding over untreated framing is a full reclad.

It allows all faults to be found and for framing to either be replaced or insitu-treated with a timber preservative or a rust preventative for steel.  Different claddings can be used which reduce stigma.  The costs are significant, but mostly predictable; typically 70% of the costs can be fixed and 30% are variable, i.e. framing replacement and the subsequent effect on linings and internal finishes.

Occasionally costs do balloon – for example once full access is gained with scaffolding, problems at roof level can be discovered, or unsuspected structural faults can be discovered once the cladding is removed.

Reclad and Modify

This is the same as recladding, but modifications may reduce weathertightness risk and/or allow improvements to enhance the building.  Better aesthetics can add value and improve saleability.  For many owners it can be a good opportunity to make such changes.

Demolish and Rebuild

This is becoming increasingly popular.  The costs should be more predictable and usually higher, but not in every case. .  It is important before any option is chosen that the cost of each option is considered.

The advantages with a new building are that treated timber or steel framing can be used throughout, so the building as a whole will be more robust.  People often like their location, but they no longer need a large house, or they prefer a lower risk style.

Sell the building

The last option is to sell as-is and to purchase another building or home.  There is less fuss and potentially lower risk.  Unfortunately we have known owners who have sold one leaky house and then bought another, so care is required.

It is important to obtain appropriate legal advice before the sale process commences.  Your lawyer can advise how best to avoid the risk of misrepresentations and to remove all vendor warranties if you have been involved in the original construction, or any subsequent alterations.

Good outcomes result from good information, proper advice and good decisions.

Please fill in the form below to speak to us about your options:

  • Please enter your message here and press SUBMIT
  • This field is for validation purposes and should be left unchanged.