Leaky Homes

The term “leaky home” is currently prominent in the media, but what is a leaky home?

Government documentation states that at some stage all external claddings will allow water to pass through into the wall framing.  If this water does not drain away or if the building owner is not aware that external water is entering into the wall framing, timber framing can become wet and start to rot.

However, there are construction types which are more at risk than others and these include those using monolithic cladding.  Monolithic cladding includes:

• Solid plaster on solid sheet backing on timber wall framing
• Textured plaster on polystyrene cladding on timber wall framing
• Textured plaster on cement based sheeting on timber wall framing

Houses built approximately between 1996 and 2008 could legally use non-treated timber for structural framing, as long as that framing was not exposed to the elements.

This timber will rot very quickly when exposed to moisture or water ingress due to the exterior cladding failing and leaking.

In 2004, councils passed new regulations for plaster system houses requiring that a cavity be formed between the plaster cladding and the exterior timber framing.  This is a cavity of approximately 20mm or greater which is formed between the exterior cladding of a building and the structural framing, using tanalised timber battens or similar.

This allows any water that does enter in through the exterior cladding to escape through the cavity before reaching the main timber structure.  This cavity also allows for greater air circulation which assists in preserving the integrity of timber framed houses.

Many plaster system houses built prior to 2004 have not been constructed using a free drainage cavity system.

Where a home is leaking, remedial work will be required to rectify any identified problems.  Remedial work may range from improving flashing details and repairs to cracks in the exterior cladding, through to a full re-clad of the property and the installation of a cavity system.  This may be an expensive and stressful exercise and some home owners have found themselves unable to afford the appropriate work.  Legal action can be undertaken either via the court system or via the Weathertight Homes Resolution Service.

During this process, the value of the property can be significantly negatively affected and the ability of the homeowner to sell the property reduced.

• Cladding
• Roofs
• Decking
• Joinery

Moisture testing will often form part of the inspection process.  This may be on request from at the time of booking an inspection, or may become part of the inspection through the discovery of potential leaking problems.  The moisture tests are carried out in the first instance using a non-invasive (i.e non-probe) moisture meter.  This allows us to test a wider range of sites without causing damage to the property.  Where high moisture readings are apparent during this process, an invasive (i.e. probe type) moisture meter can be used.  This will often require the approval of the property owner.