Is your roof leaking? 


04 803 34 79

chimney strengthening


Chimney Strengthening

When strengthening chimneys it should be understood that each chimney and its location are different. Always take advice from a structural engineer before performing any alterations to your chimney.


The line drawing below shows a chimney removed to ceiling level. The chimney is still in use and has been replaced with a light weight metal replacement. It is important to provide a diaphragm brace to the top of the chimney. This will provide added protection to the remaining stack under earthquake load.



Where removal of the chimney is not possible, it should be braced or strengthened. The image below shows a braced chimney. All corners of the chimney are braced with angular galvanized iron. The corners are fixed to form a frame around the chimney. The frame should be bolted tight in situ to compress the chimney column. Diaphragms are fixed at roof height and ceiling height to distribute horizontal pressure.    



Where the chimney breast sits adjacent the property, galvanized bands may be used to give extra support.


 Click here for chimney removal in greater wellington.