Repair options

It is important that leaky homes are repaired as soon as problems become apparent.

How bad is it?

If you suspect you have a leaky home it is essential to get expert help. This is because water entering at the roof level can appear to be coming from the base of a wall some distance away, or a small damp area of carpet might be the only visible sign of major problems. It is important that the source of any leaks is identified and dealt with and this may take several attempts.

It is important that leaky homes are repaired as soon as problems become apparent. This will prevent further damage occurring, and so minimise additional repair costs.

When the source of a leak has been found, other potential problem areas need to be inspected. If the leak is an isolated loose flashing then this can be easily rectified. If the leak is due to an issue that is repeated around the house, such as a lack of window flashings, then the problem is likely to be much wider.

In this case a check for high moisture levels within the timber frame needs to be made. Initially this can be made with a non-destructive moisture meter. However, if extensive areas of moisture are found, or if the results do not appear to be consistent, further investigation needs to be made. This is done with a pronged moisture meter through small holes drilled in the walls. This tests the moisture levels in the timber itself.

If there are signs of moisture in several areas, further investigation by removing wall linings may be warranted. This is often the only reliable means of discovering the full extent of water entry. It is also important to determine if the timber framing has been treated, as this will determine the extent of structural damage. Timber only treated with boron to deter borer, will provide limited protection against the spread of mould.

Mould will develop in untreated timber far more readily and may spread beyond the immediately affected area. Mould found in the timber framing will need to be identified. Stachybotrys can be a health risk for some people once it has been exposed.

Only when the extent of any problem is clearly established can decisions about repairs be made. If your home was built within the last ten years you can contact the Weathertight Homes Resolution Service or take action through the courts. You should get legal advice to assist you in your decision. See what to do if you have a leaky home for more information.

Repair, replace or redesign

If the problem is an isolated one, has not been occurring for too long, and the damage is limited, then a simple repair may be in order. This is possible where a leak occurs only in certain weather conditions, for example, or an isolated leak has been found quickly before extensive damage could occur.

If the problem is isolated but has been occurring over some time and has caused rot, the wall will need to be exposed. The damaged framing, all mould affected and rotting timber will need to be removed and disposed of. The damaged materials will then need to be replaced and the leak repaired. Note that repairs that require the replacement of part of afailed cladding system will require a Building Consent.

Where many leaks have occurred due to poor weatherproof detailing, additional work will need to be carried out on top of removing and replacing damaged materials. For example missing flashings need to be rectified for the whole building to ensure leaks do not recur. This may involve more expensive detailing than originally used. The Acceptable Solution for weathertightness E2/AS1 will guide this decision.