Collar Ties

Collar ties span between and connect opposing rafters, and they are typically placed in the top third of the attic spaces. Collar ties hold the rafters down against the ridge board and, to an extent, help prevent rafter spread. Home inspectors should take note of attics without collar ties, especially where the rafters run perpendicular to the joists. Collar ties must be at least 1x4 (nominal) and spaced not more than 4 feet on center. A lack of collar ties may allow roof rafters to separate and cause sagging of the roof's ridge and structure.www.nachi.org

A crack that forms a V-shape may indicate heaving. The illustration above shows a V-shape open crack in a foundation wall indicating heaving from the ground under the foundation footing. The ground in the illustration is expanding and pushing upward on the footing and foundation, causing a crack. This observation by a home inspector would be reported as a major structural concern and defect with correction and further evaluation & repair by a licensed foundation contractor or structural engineer

A brick wall is not necessarily considered to be waterproof. Water can penetrate through a masonry crack that is hairline or as small as 1/100th of an inch (0.3 mm). And masonry exterior-covering materials (siding) is porous and can absorb moisture during a weather event.

inspectors should look for and note:

A slab-on-grade foundation is a type of foundation consisting of a structural concrete slab poured onto the ground, but usually, there is a layer of gravel and a vapor retarder between the ground and concrete. View illustration of a slab-on-grade installation. No accessible space exists in slab-on-grade construction. Slab-on-grade foundations are popular in areas where there is a high water table. For example, there are very few full basements in Southern Florida. In general terms, a slab-on-grade foundation is poured on the grade or ground. complements of InterNachi @ www.nachi.org

This is often seen by the home inspector as the supply conduit to outside installations, such as air-conditioning compressors.

Knob-and-Tube

Knob-and-tube wiring is so named because of the porcelain fittings used to support and insulate the conductors from the timber components in the home. The knob holds the wire away from rafters and joists, while the tubes are inserted into holes bored though joists and studs to protect the conductor and its rubber insulation.

Circuit Breaker Panels

These are probably the most common type that home inspectors will come across, as they have replaced fuse panels over the last 40 years or so. As we saw for fuse panels, breakers are far from foolproof and require some particular checking.

Remote Distribution Panels

Although this topic is covered in other areas, because the emphasis is on safety, it's important to review.