Roof inspection
An inspection earns its cost when it answers a decision. In a state with housing this old, the decisions are specific: what is actually under the covering, whether the framing has moved, and whether the ice that appears at the eaves every winter is a roofing problem or a heating one.
When it earns its price
Before buying, above all — on a nineteenth-century house the roof is one of the largest numbers hiding in the purchase, and a general home inspection rarely establishes the layer count, the sheathing type or whether a sag is old and settled or still moving. Before winter, on an ageing covering: the freeze finds every loose edge, and finding them in September costs less than finding them in February. And on any house that ices at the eaves each year, because that symptom is worth diagnosing before it is worth roofing over.
What gets checked
On the roof: what the covering is and how many layers it appears to be; whether the edges are still sealed; the difference between the north and south slopes, and how much moss is established; every wall junction and whether the flashing is layered metal or sealant doing the work; the uphill side of every chimney, and whether a cricket exists; the valleys and what sits in them; and the ridge line, sighted along its length for deflection.
Off the roof: the attic, where most of the real story is. Whether intake exists and is open rather than buried, rust on nail points (condensation, not a leak), staining on the underside of the deck, daylight at penetrations, and — on old houses — what the framing actually is and whether anything has moved. And in winter, the single most informative observation available: how the snow melts off the roof, which says more about the house than any measurement.
What the report is good for
A written report turns impressions into decisions. For a buyer it puts a number on the largest hidden item in the purchase, and distinguishes a settled century-old sag from a structural problem. For an owner it fixes the scope, so three bidders price the same deck assumption, the same layer count and the same ventilation work — the only way a comparison between quotes means anything. And it puts the job in the right season: identified in spring, quoted properly, installed in the warm months when the covering will actually seal.