It's hard to answer this question as you haven't specified what parts areas or surfaces. All masonry and external surfaces are designed to keep out the elements however alongside working with them, they are designed to breath so will take in certain amounts of water aswell. The best way to decide whether you need works or waterproofing is when the surfaces deteriorate visibly, ie, Render/pebbledash cracks or becomes hollow, brick/stone blows or spauls revealing the belly, mortar becomes sandy or soft. If any of these surfaces are painted, hairline cracks, blistering or discolouration is a sure fire way of getting to action to have everything repainted. By all means send us a message and I can give you an answer directly to your specific enquiry.