I've seen similar before, and it's true, it is avoidable.
Monitoring plant growth can prevent disasters
For an evergreen climber or ground cover the Ivy (Hedera sp) is an ideal candidate. It has vigorous growth and is almost indestructible. But these ideal growth characteristics can have a detrimental effect on older buildings.
This small brick shed (right) is a prime example. The building is quite old, but was solid and weather proof; the roof was water tight, rain would just run off the roof as it was supposed to do so.
About 18 years ago the owners decided to plant some ivy at its base, in an attempt to grow the ivy up the walls to mask the brickwork and give the shed a quaint appearance.
The ivy did what ivy does best and grew and grew as if it was one of Jack's magic beans. After a number of years the shed was completely covered by the ivy. Birds would come and feast on the ivy's fruit, the occasional mouse would make a nest, and the walls provided the perfect green backdrop for the display of container grown plants.
Without any indications to the owners, the ivy had grown so well it was now creeping under the roof tiles and starting to dislodge one or two tiles. A bit of damp started to seep into the roof rafters and over time more tiles became dislodged. The dislodged tiles only became apparent when a large puddle was found in the shed after heavy rainfall overnight.
Unfortunately by the time the puddle was discovered the roof rafters - hidden by a ceiling - had become badly rotted. The roof needed to be fixed, which required the removal of the ivy and roof tiles.
A section of ivy was removed, and a close inspection of the ivy revealed that aerial roots had penetrated between the bricks and mortar, dislodging the mortar. It was decided that all the ivy should be removed, but unbeknown to the owners, removing the ivy would lead to the demise of their shed.
As the ivy was removed it was discovered that the penetration of the roots and stems between the mortar and brick was far worse than first thought. Essentially the ivy, which had caused the problems with the roof tiles and displacement of the mortar, was now holding the building together!
Ivy based demolition
As the last few remaining stems of the ivy were removed, the roof started to sag, and eventually without any assistance caved in and fell to the floor of the shed. The knock on effect was that the upper parts of the walls began to bow slightly, and large gaps between the bricks could be seen where the mortar had been dislodged. The walls were now unsafe and fell over with a slight push, transforming the once stable weather proof brick shed into little more than a pile of rubble.
Periodic monitoring of the ivy would have prevented the building getting into an unsafe condition. The building was old, but would probably still be standing if the growth of the ivy had been checked. Fortunately it was just a small outbuilding, the ramifications of unchecked ivy growth could have been far worse if the same damage was done to a house or other large building. Don't let your building become a victim of ivy; monitor the growth of the plant and take appropriate action as and when required.