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 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:

nearby vegetation

The inspector is required to report vegetation growing near the home according to the Home Inspection Standards of Practice. The home inspector should note the existence of any trees near the home, because the roots may affect the foundation or underground drainage pipes. Plants growing next to a house could raise the soil level too high against the foundation.

steep slope

The home inspector should note if a home is on a steep slope and, therefore, subject to erosion or movement. The maximum slope of a lot should be roughly 1-in-2.

There are two common styles of wood framing: balloon and platform. The main difference between balloon and platform framing is apparent at the floor lines. The balloon wall studs extend from the sill of the foundation all the way to the top plate of the second floor. The platform framed wall, on the other hand, is independent for each floor.

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

Common Structural Terms

In this section of the course, let's learn about some common terms or phrases that are used in the construction and building industry, particularly related to a residential building. Understanding construction terminology and knowing the purposes of building components and framing members (for example, studs, plates, load-bearing walls) will help a home inspector to do a better home inspection. Even though most building components are not readily accessible and are not readily visible to a home inspector performing a home inspection on an existing (already built house), it's important to know how buildings and homes are built. Sometimes defects can be seen by a home inspector, because the hidden, covered, or inaccessible system or component has a problem.

What's an Arc Flash?

An arc flash occurs when a flashover of electric current leaves its intended path and travels through the air from one conductor to another, or to neutral or ground. It often happens unexpectedly and can be explosive but brief, or it can last seconds and be rather visually spectacular. It can cause a little damage or it can disable a system and require the replacement of equipment. An arc flash of any size is quite dangerous because its path is unpredictable; it will be attracted to the nearest item with the greatest conductivity, such as an unsuspecting rodent or house pet, or a person. An arc flash can cause a serious electrical burn or even fatal electrocution.

All electrical systems require a means of disconnection so that the service can be shut down quickly if any dangerous conditions exist. In this section, we will look at the types of disconnects, and the common problems that need to be reported.