Hidden danger in jarred chimneys

Chimneys still standing above the roof line could be fragile. Photo / Laura Hall

The damage to hundreds of brick chimneys in Christchurch may be under the roofline and not visible, and residents are being warned to treat them as dangerous until they can be inspected.

Christchurch roofer Tony Stuart, who spent most of Saturday repairing roofs and inspecting and removing damaged brick chimneys following the earthquake, said visible damage could be only part of the picture.

Mr Stuart said he removed one chimney down to the roofline and covered the hole with roofing iron.

However, below the roofline the chimney had moved on the base and further inspection was needed because it could be unstable.

Other chimneys still standing above the roof line could be fragile.

"In lots of chimneys, bricks have gone from the lower part of the chimney but the top part is still there, which makes it really dangerous," Mr Stuart said.

"There is bugger all supporting the top of it and bricks are really heavy.

"In many chimneys, the mortar holding the bricks together is just sand and cement but over the years it has lost its capacity to hold the bricks together. The bricks are just stacked on top of each other."

Mr Stuart said people could visually inspect their chimneys from the ground but the rest should be left to experts.

"They need to get a roofing company to check their roofs and chimneys.

"They shouldn't get up there themselves. It is too dangerous, but they need to be checked," he said.

"Often you can't see the cracks that have appeared around the chimneys until you get up there on the roof."

Mr Stuart said that before the earthquake, he had removed many brick chimneys and in most cases just picked the bricks off.

"We didn't even have to knock them or do anything."

- NZPA