I have purchased a 200year old Cob cottage in Exeter which I am restoring. The cob is still in reasonable condition. The interior walls of the house have been skimed in a layer of gypsum plaster to give a sheem finish. I was advised that it will be difficult to scrape off the gypsom layer and will create more damage to the cob. Uunfortunately this was done many years ago and is starting to come off in a few placees. How can I best finish the walls? thanks
Thanks for your question. It would be best to carefully remove the gypsum, but there is a chance this can damage the underlying substrate and this will/may need to be addressed accordingly. Unfortunately until you start to remove it you won’t know how the cob will be affected.