It can be difficult to carry out DIY repairs on chimneys because specialist equipment should be used to make the job safe and secure. With that in mind, we would suggest that you ask a local roofer to carry out chimney repairs. Chimneys are constantly subjected to wind, rain, sun, ice, frost as well as pollution and other environmental factors that all contribute to slow erosion of mortar, lead and brick work. If you notice any of these signs on your chimney stack, call a roofer for a professional opinion.