Roof inspection
An inspection earns its cost when it answers a decision. In a region where a building can carry a pitched front roof, a flat rear one and a porch roof nobody has looked at in twenty years, the most valuable thing it produces is simply knowing what is up there and which part is on which clock.
When it earns its price
Before buying, especially on a multi-family: roof condition is one of the largest numbers hiding in a purchase here, and a general home inspector’s note rarely distinguishes between a membrane with ten years left and one that is finished. When a flat roof passes twenty years, because that is when the covering starts making the decision rather than the owner. And when ice returns to the same eave every February, since the useful question is whether the problem is the roof or the attic, and the answer changes what you buy.
What gets checked
On a pitched section: the covering and its apparent age, granule loss, the difference between the sunny and shaded slopes, the valleys and what sits in them, and step and counter-flashing at every wall and chimney. On a flat section: the seams, the parapet junction, the base of every penetration, the condition of the drains or scuppers, and whether water is standing anywhere after rain. And on any multi-family, the rear porch roof and its tie-in, the part most likely to be leaking and least likely to have been looked at.
Then the attic, which on housing this old carries half the story. Is there any ventilation at all? Was the soffit intake buried under blown insulation years ago? Are the boards overhead continuous or spaced? Rusted nail tips and staining mean moisture is condensing under the deck, and a bath fan discharging into the attic instead of outdoors is a roof problem disguised as a plumbing one.
What the report is good for
Photographs are what turn an opinion into something you can hand to someone else. On a three-family, where the gap between “fine” and « finished » runs to tens of thousands, that evidence is what a purchase negotiation actually rests on.
A dated report also puts a season on the work instead of a vague « soon », which is how you end up quoting in February for a June job rather than calling in September. And it fixes the scope: three bidders pricing the same sections, the same materials and the same porch roof are finally comparable.
What an inspection should settle on a three-decker
- What does a roof inspection look at on a three-decker that a buyer's general inspection does not?
- The flat rear roof and the porch stack, mostly. A general inspection confirms the pitched front roof is there; a roofing inspection walks the membrane for open seams, blisters and ponding marks, looks down the scupper throat, and counts the porch roofs where they meet the wall. From the attic it reads the boards under the covering (on a house this age they were laid with gaps, sized for slate) and counts layers from the nail tips.
- Can a roof be inspected with snow on it?
- The house can; the covering waits. Boston averages about forty-five inches of snow a year and close to ninety nights at or below freezing, by NOAA's records at Logan over the last decade, and a February visit reads what that does to the attic: the melt line on the deck, frost on the nail points, ice at the cold edge. The shingle and the membrane get their turn on a dry spring day.
- How do you tell how many layers are on the pitched roof without opening it?
- From the rake, where the edge profile shows each course stacked on the last, and from the attic, where the length of the nail tips coming through the deck tells the same story. Two layers is the limit, and a report that does not say how many are there has skipped the question that decides whether the next job is a strip.
- Does the inspection cover the membrane on the flat section, or just the shingles?
- It has to cover both, because they age on different clocks. The membrane is usually the older of the two and the one nobody has looked at, and the report should say where it was told to drain, whether the scupper is open, and whether the parapet cap is still doing its job.
- What actually fails a roof inspection on a house like this?
- On the pitched section: exposed nails, cracked or lifted flashing at a wall or chimney, and granule loss heavy enough to leave bald patches. On the flat section: open seams, a parapet cap that has separated from the wall, and standing water more than a day or two after rain. Any one of those items can fail a report on a roof that otherwise has years left, which is why the fix is often smaller than the finding sounds.
- Why do I keep getting calls about roof inspections?
- Most of those calls come from lists sold to canvassing outfits working three-decker neighborhoods block by block, not from anyone who has actually looked at your roof. A real inspection is one you book yourself, tied to a reason you can name: buying a building, timing a flat-roof replacement, or figuring out why the same eave ices every February. Nobody who has genuinely assessed your roof calls you first about it.
- 1 Ridge caps. The thinnest pieces up there, and the first to work loose over a hard winter.
- 2 The field. Slate on the older stock, shingle on the rest. They age on very different clocks.
- 3 Valleys. Leaf litter mats in them, and two slopes then drain through one line.
- 4 Flashing. Old masonry chimneys, and the porch roof that meets the wall three stories up.
- 5 The vent boot. Rubber that hardens and splits well ahead of the covering it sits in.
- 6 Eaves and ice dams. Where meltwater refreezes at the cold edge and backs up under the courses.