Lime mortar with modern materials All manner of questions and solutions to problems and issues surrounding the subject of brickwork, blockwork and stonework

[Justaddwater]

I'm looking to build some piers alongside a bungaroosh wall to add support. I'm thinking about a single concrete block laid flat and tied to wall where possible with stainless frame ties, then wrapping the blocks with brickwork.

My question is: Would it be ok to use sand and cement for the new work as it is its own structure, or do I need to be using hydraulic lime? If so, can you use lime with concrete blocks?

I can't seem to find any info about this online, other than using a lime render on concrete blocks.

[stoneyboy]

Hi justaddwater,
The problem as I see it is that you are proposing very rigid piers supporting a flexible bungaroosh wall, it would not matter which type of mortar you use.
Suggest you build your piers in soft clay bricks laid with lime mortar and tie these to the wall using stainless wire cavity ties (which will allow limited movement). You will have to cut pockets in the wall for anchoring the ties.
Regards S

[Justaddwater]

Thanks Stoneyboy.
Could I use concrete blocks in the middle to save on materials, but obviously using lime?

[stoneyboy]

Hi justaddwater,
If you are adding piers to move with and support the wall you will need maximum flexibility in the piers. Concrete blocks will not achieve this which is why a wholly brick pier with many more joints is preferable.
If you are adding piers to prop the bungaroosh wall then you could use concrete blocks.
Regards S