2.2 Roofing & Structure

Roof Coverings

The inspector identifies the covering, estimates remaining life, and reports defects — but does not certify or warranty the roof. The dominant material is the asphalt (composition) shingle, available as 3-tab or architectural (laminated). Aging signs include granule loss (bare, shiny asphalt and granules in gutters), curling and cupping, brittleness (shingles crack at edges and penetrations), and nail pops where fasteners back out from thermal cycling. Other coverings each have a signature failure mode:

Inspectors avoid walking brittle or steep roofs and may inspect from the eaves, ladder, or with binoculars or a drone, disclosing the method.

Flashing & Roof Drainage

Most leaks begin at flashing, not in the open field. The inspector checks every transition and penetration: valleys, chimneys (which need both base/step flashing and a counter-flashing let into the masonry), skylights, plumbing vent boots (the rubber gasket cracks with UV), and sidewalls. At a sidewall, step flashing — short overlapping pieces, one per shingle course — is required; a single continuous L-flashing there is a defective installation that channels water behind the cladding. Rust, missing sealant, reverse laps, and roofing cement smeared as a permanent repair are all reported.

Roof drainage moves water off and away. 1). Undersized or clogged gutters back water up under the eaves, rotting the fascia and roof deck and feeding ice dams in cold climates. The inspector also reports a missing or damaged kick-out (diverter) flashing where a roof edge meets a wall above a lower roof — its absence dumps concentrated runoff into the wall and is a frequent hidden source of sidewall rot.

The Structure: Foundation & Framing

Foundation types drive the inspection approach:

• Slab-on-grade — no crawlspace; plumbing is in or under the slab, so leaks are hard to see. Inspect for cracks, heaving, and moisture intrusion at the perimeter.
• Crawlspace — inspect for moisture, a vapor barrier, adequate ventilation or proper encapsulation, rot, pests, and adequate support.
• Basement — inspect walls for cracking and bowing, and for water-entry evidence (efflorescence, stains, sump activity).

Crack interpretation is the core analytical skill. Vertical cracks (within ~30° of vertical) usually indicate settlement and are the least alarming. Horizontal cracks are the most serious — they indicate structural loading from soil/hydrostatic pressure exceeding the wall's capacity, often with inward bowing. Stair-step cracks in block or brick signal differential settlement. As a rule of thumb, hairline cracks under ~1/16 inch are minor; cracks over ~¼ inch, any horizontal crack, and any bowing warrant evaluation by a structural engineer.

Framing — joists, rafters, trusses, and beams — is inspected for sag, deflection, cut or notched members, rot, pest damage, and modified or cut trusses (a serious defect, since engineered trusses must never be field-altered).

Reading the Structure as a Load Path

Structural inspection follows the load path — the route by which weight travels from the roof down through walls, floors, beams, and posts into the foundation and soil. A defect anywhere along that path shows up elsewhere: an undersized or rotted girder lets the floor above it sag, a settling pier cracks the wall it supports, and a failing foundation telegraphs diagonal cracks up to the door and window corners. The inspector looks for consistency between symptoms — a sloping floor over a crawlspace with a sagging beam and a cracked exterior wall on the same side describes a single settlement story, not three unrelated problems.

Key framing concerns include over-spanned or over-notched joists (notching is limited to the outer thirds and to a fraction of joist depth), missing or rotated joist hangers, bearing (each member needs adequate end support, typically about 1½ inches on wood), water and termite damage at sills and rim joists near grade, and previous repairs such as sistered joists or added posts that hint at a history of movement.

Active vs. Dormant Movement

The critical judgment is whether movement is active (ongoing) or dormant (stabilized long ago). Clues to active movement include fresh, clean crack faces, cracks that are wider at one end (differential settlement), doors and windows that stick or won't latch, separation at trim, and recently displaced finishes. Old cracks that have been painted over, with patched and stable edges, suggest movement that has stopped.

Because an inspector cannot monitor a building over time in a single visit, the proper response to suspected active structural movement is to report it clearly, describe the evidence, and recommend evaluation by a licensed structural engineer — never to certify the structure as sound or condemn it. This restraint mirrors the SOP scope rule from the previous section and recurs throughout structural reporting.

Chimneys and the 3-2-10 Rule

Masonry chimney height is governed by the 3-2-10 rule: the chimney must extend at least 3 feet above the roof penetration and at least 2 feet higher than any part of the structure within 10 feet (measured horizontally). A chimney that is too short draws poorly and can backdraft combustion gases. Inspectors also check the crown for cracks, the flashing and cricket (a saddle on the high side of chimneys wider than ~30 inches that diverts water), spalling brick, and a rain cap with spark arrestor — chimney and fireplace findings are weighted heavily on the NHIE.