A survey exists to answer three questions: what is actually wrong, how urgent is it, and what will it cost to put right. We answer all three in writing, with photographs, and at no charge, because the survey is how we earn the work rather than something to charge for up front.
One of our teams gets onto the roof and, where access allows, into the loft. We look at the condition of tiles or slates, fixings, ridge and hip bedding, verges, valleys, all flashings and leadwork, the chimney stack, the underlay, the timbers, ventilation, insulation and the entire roofline and rainwater system. Everything is photographed, including the parts of the roof you will never climb up to inspect.
You then get a plain-language explanation. If the roof is sound, we will say so. If a targeted repair will genuinely see you right for years, we will tell you that too, recommending a new roof to somebody who does not need one is how contractors lose a street's worth of future work. Where replacement is the honest answer, you get a written quotation to compare against the repair option.