Re-rendering a 250 year old house

Hello walker1234_61 A couple a questions for your consideration; Do you when the roughcast was applied? Is it a modern tyrolean or Edwardian roughcast? How exposed are the elevations and are there any fractures in the render you can see? Is there an issue with damp at the property? When were rainwater goods last checked? If your buildings elevations are highly exposed to the elements then the Edwardians will have used a cementitious render to cover some nice Georgian architectural detailing. It wont be long before thermal movement in the Georgian building fabric will cause fractures in the render trapping moisture to which a whole raft of issues could potentially arise. On the other hand if your building age is not as accurate as you have been made to believe and its slightly younger then potentially the brick work could have been laid around 1850 when OPC (ordinary portland cement) had been patented a few years earlier in which case no real major issues will occur. Preventative maintenance is key here. There will be people selling a service and wanting you to just go the 'whole hog' as it were. If there is an issue other than aesthetics for you then I suggest you find the cause to the problem then a cost effective solution can be made. Historic structures need to be able to transfer moisture vapour through the fabric. This process is know as breathability, rendering straight onto your existing roughcast will change the dew point in the walls affecting interstitial condensation etc. This should help. Chris EHR

You can go the whole hog & have it all rendered but you can usually go round n tap rendering to see if it sounds hollow. if not hollow much round building then just get rendering done were needed saving you time n money. I hope this helps. Alan @ Jetflow drains