We all know that natural stone coping stones and pier caps will provide a stunning finish to a wall but equally that they can be prone to getting knocked off and damaged. People will always sit on or lean against walls and the fact that coping stones and pier caps are exposed means that the weight of a person leaning on them can easily be enough to break the bond between the coping stone/pier cap and the bedding layer. Also lets bear in mind that coping stones and pier caps can be expensive, especially when made from Yorkstone & Portland Stone, so any damage caused can be very costly to repair. There is however a very simple step that can be taken to significantly increase the strength and stability of coping stone and pier caps. Its called a bond bridge. A bond bridge is a mixture of SBR (exterior pva) and cement slurry which is painted onto the back of natural stone to enhance the adhesion between stone and bedding layer. You can also add a small quantity to the mortar mix as well. The results are quite staggering and have to be seen to be believed. When a bond bridge has been properly applied it is extremely difficult to separate the coping stone or pier cap from the bedding layer without the use of extreme force. I have even heard in some cases of the actual stone breaking before the bond does. Bond bridges can also be used for natural stone paving, especially when dense, low porosity stones like granite and slate paving are being used.
Try it for yourself, it only takes a little bit more effort and you can get complete peace of mind that the coping stones you installed today will still be looking great tomorrow and for years to come.