A question for fire risk assessors. Both of these properties have two or more residences. The external walls are masonry but there is some decorative cladding. How concerned should I be in light of the requirements for external wall consideration in the fire risk assessment.

Its only an issue over 11m

It has to be considered no matter what the height - the law is clear on this. However the likelihood of being  other than low risk is small, the height being one of the factors to consider when assessing the risk.

Building regulations say that when building work is undertake on an existing building it should ensure that the building is no worse in terms of compliance than it was before the work started. However, there is no requirement to improve the levels of compliance.

It is an established principle that building regulations should not be applied retrospectively. The ‘non worsening’ clause recognises that it may not be feasible to try and apply modern standards to old buildings.

If it was compliant, then it still is compliant as the changes to cladding are only above 11m

Building Regulations do indeed still have the statutory bar. Fire Safety Regulations don't as it was removed with the repeal of the Fire Precautions Act which used to take the same approach with fire certificates (which led to some rather outdated precautions remaining in place well past their inadequacy was fatally proved).

This means that whilst there is no automatic requirement to upgrade something (unless explicit in a regulation under the Order) it can't be automatically accepted either just because it was OK 20+ years ago - this is where the risk assessment process comes in.

External walls, including balconies and windows etc are explicitly required to be assessed for fire risk in all premises with 2 or more dwellings - however this risk assessment is likely to find most low rise blocks low risk partly because the building standards for these hasn't required high standards of fire performance and still doesn't so it would be wrong to require a higher standard than even a new build requires!

So basically for the buildings shown constructed of sandstone blocks and brick, its not an issue