Why did the “Leaky Homes” crisis happen?
Leaky Homes were a result of a whole heap of bad design decisions happening at that time.
These were the 3 main issues:
- Monolithic cladding (like plaster)
- No cavity (plaster was fixed directly to the structure)
- Bad design trends of the time (flat roofs and no eaves)
In 1993, a new building code came into practice at the same time more homes were being built in a Mediterranean style.
This style of home had flat roofs, no eaves, and was built with plaster – rather than the tried-and-true brick facade.
Monolithic cladding was the material to give properties that sleek Morrocan-esque, seamless look.
But plaster wasn’t the issue; it was the way the plaster was used in the overall design.
Water passes through all cladding – not just plaster (like everyone thinks it is) but bricks too.
The building industry has known this since the early 1900s, which is why brick homes were built with a 30-60mm cavity (or a gap) between the external cladding wall and the interior structure.
The brick you see on the outside is the wallpaper that makes it look pretty. Behind that you've got a gap of about 30-60mm, then you've got the framing and structure of the actual house.
But around this time these homes were built with timber frames, and the exterior cladding (the plaster) was attached directly to the structure (e.g. it was touching the timber behind it).
The only line of defence between the elements and the timber structure holding up your house was a 3mm coat of paint.
Granted, it was wicked cool paint designed especially for the job of waterproofing, but this is not infallible.
And because the roof was flat the water would pool for longer than it should, and when it did finally roll off, it rolled directly down the walls. Again leaking in the timber structure.
To make matters worse the timber was often untreated and would rot quickly because water got to it.
Everything seemed fine for the first 3-5 years, and then the problems started.