One of the big things I get asked is about leaking condos, or rain screening.
The term ‘leaky condo’ is pretty specific to the lower mainland, and refers to many of the condo buildings built between the late 1980s and mid 1990s, though not limited to this era.
It came about due to a construction boom that was occurring at that time. Designers from other parts of the world, namely California, were brought to lower mainland to help keep up with the demand for buildings.
The issue with the design during this time, in easy terms, is that moisture would not be allowed to vacate the wall cavity. Instead it would remain in the wall cavity which would cause rot, mould, or other structural issues over time.
A few other matters exasperated things. A material called Exterior Insulation and Finish System (EIFS) was used. Also building code at the time encouraged builders not to include overhangs on a building, therefore there was no shield from the elements.
It was quite prevalent, and resulted in the collapse of the previous non-mandatory home warranty system. It also resulted in the establishment of the Homeowners Protection Office, new standards for construction, and new building code. It also resulted in financial assistance programs available to those that could not afford the levies from their stratas.
A new wall assembly system was developed which commonly referred to as Rain Screen
This type of wall system essentially, again in easy terms, allows moisture that either penetrates, or remains within the wall system, to escape through a gap.
This gap also allows air to circulate, so that it can reduce the chance of rot forming from consistent contact with moisture.
Rain screening became a requirement in 1996 in Vancouver for all buildings, and in 2006 for coastal areas in the remainder of BC.
You can easily tell if a building has a rain screen by feeling under the exterior wall. If you feel a gap under it, likely its been updated with a rain screen.
Another way to figure out of a building is rain screened, is observe the exterior wall. If there are what appear to be ‘sections’ separated by flashing, its likely been rain screened. The key is to look for that gap under the wall.
Horizontal plank style cladding, such as vinyl, wood, or hardiboard, naturally act as a rain screen based on how it was installed. They will already have air gaps underneath the material due to the nature of the ‘plank’ style of cladding.