Beyond DIY I know, but just in case anyone has any insight here. The picture I've placed here is detail from two Georgian, grade II listed buildings, in different parts of hampshire
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Both cladding faces are on the weather faces. I suspect the original cladding has failed , but because people live in these buildings and don't want damp, but historically significant original materials underlie , then these modern cladding structures have been laid over to retain the original. With a normal un-listed building you'd strip off the failed cladding and replace with modern materials. Anyone know a term for this protruding protective frame and cladding arrangement might be called and its internal structure? Would there be a steel frame , fixed peripherally only, so no fixings pass through the original cladding, or parhaps fixings only every metre or so (windage effects could be enormous over such an area if unbraced , I would have thought)? The top one , the modern material is hanging tiles, protruding out almost the soffit width, looks reasonable. The lower example looks terrible, 2 stories high , 30 foot wide of unrelieved area of fibre-cement "slates" . The lead dressing at the top shows the degree of protrusion. The area above it is mid 19C pebbledash, equally ugly. Then what is the heritage rationale to completely cover over, if no one can see the original surface, rather than injecting wiht silicone treatment say?