First and foremost, good information is essential to inform good decision-making. Your first action should be to engage a building surveyor to carry out an investigation and provide a report.
Investigation and reporting
Generally, this takes the form of an initial investigation, followed by the necessary detailed and invasive investigation and report. The level of detail in the report will depend on whether legal action is being contemplated, and if repair is to take place before or after legal action is completed.
Once you have the required information, you can then consider repair options.
Why repair a leaky building?
There is no obligation to repair a leaky building, unless the building is dangerous or insanitary. However, if you choose to ignore a weathertightness issue, it will not go away. Instead:
- The extent of the damage caused by the leakage will continue to grow, sometimes adding considerably to the eventual cost of repair.
- People in the building risk health-related problems caused by allergenic or toxic reaction to certain mould, bacteria or dust mites.
- The time limit imposed by the Building Act long-stop provision on an owner’s eligibility to place a claim may expire.
For these reasons it is better to investigate the nature and extent of the problem and try to fix it as soon as possible.
Leaky buildings that must be repaired
The Building Act 2004 requires each territorial authority to have a Dangerous and Insanitary Building Policy, which describes the actions that must be taken when a building is deemed dangerous or insanitary.
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 with leaky buildings is that certain mould spores contain mycotoxins (chemical toxins) within their ‘shell’. 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 immunosuppressive illnesses.
Leaky building repair options
There are several different options when it comes to repairing a leaky building, with various pros and cons, which are detailed below. After a detailed investigation, your building surveyor will be able to advise you on options for repair.
Repair options include:
- Emergency repairs
- Targeted repairs
- Partial reclad
- Over cladding
- Full reclad
- Reclad and modify
- Demolish and rebuild
- Don’t repair
Emergency repairs
Emergency 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 to fix defects were the norm. More recently, the focus shifted from not only fixing the defects, to correcting the inadequate systems (such as cladding) that contributed to them.
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 is required, and ‘what is the level and type of timber framing treatment?’
It is quite possible in post 2004 buildings with a cavity and treated framing, 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 building 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
A partial reclad is possible where there are localised risks and faults on some of the elevations, or there are different lower-risk claddings. However, a building with three reclad elevations and one not repaired may reduce confidence among potential buyers, and therefore value. In the case of a part brick-veneer and plaster-clad house, a partial reclad is often sensible.
Over-cladding
Fixing new cladding over the original cladding can offer cost savings over a full reclad. However, when over-cladding, the building 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 to consider.
Whilst over-cladding from a weathertightness point of view may seem satisfactory, it can leave an unpleasant legacy that is difficult and expensive to rectify. The cost saving of not removing the original cladding should always be weighed against the risks of leaving it in place.
Full reclad
The default option for monolithic cladding over untreated framing is a full reclad. This allows all faults to be found and for framing to either be replaced or treated in situ with a timber preservative or a rust preventative for steel. Different claddings can be used which reduce stigma associated with certain cladding types.
The costs of a full reclad 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
While undertaking a reclad, modifications can also be carried out to reduce weathertightness risk and/or to 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 option is becoming increasingly popular. The costs are usually higher but should be more predictable, although this is not the case with every rebuild. It is important to weigh up the costs and benefits of repairing or rebuilding before choosing a course of action.
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. Building owners often don’t want to move to a different location, but can build something that better suits their current needs.
Don’t repair
A final option – if the building is not deemed dangerous or insanitary – is not to repair, and either keep using the building in its current state, or sell it as it is.
It is important to consider the potential health issues for people who live in or use a leaky building, such as those caused by allergenic or toxic reaction to certain mould, bacteria or dust mites.
Selling a leaky building may be a good option for those who don’t want the hassle and risk associated with undergoing a potentially lengthy and expensive investigation and repair process.
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.
In every case, the best outcomes result from good information, proper advice and informed decisions. Prendos can provide expert advice to help you make the right decisions about a leaky building. For more information see Weathertightness and leaky buildings.