Nashville Home Inspections
Brentwood Home Inspections
Middle Tennessee Home Inspections
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This page will soon have information about the "Standards of Practice" for inspecting structures as well as other helpful information as well. Some of the information will be pertinent to this site only, while some information will link to other sites. I hope that you find this information helpful. Feel free to make comments. I will add these as posts to this site. To make a comment click here. |
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Blog Roll - Structure
Improper Notching - Engineered Lumber
 Improper support
Improper column |
From the basement or crawlspace, the home inspector will report on the condition of the supporting structures such as columns and the visible framing overhead. Columns: Posts and columns are vertical supports that carry the weight of the structure from the girders (or beams) to the ground. Columns transmit the weight to footings below. It is not unusual to find columns or posts put in to support an unusually heavy load such as a piano. These are ancillary supports which need to be evaluated for structural integrity as well. As per the standards of practice, the inspector needs to identify the materials used in column construction – steel, wood, or masonry. Columns should be inspected for their condition and ability to support the structure above.
The inspector will determine if the column or post is doing a proper job of supporting the structure above:
Inspectors may see shims of metal or hardwood inserted between the beam and column. The shim should be large enough to cover the interface between the beam and column. If it’s too small, the beam or top of the column may be crushed. The inspector will report on damaged or crushed shims.
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 Improper shims under girder
Improperly supported girder |
From the basement or crawlspace, the home inspector will report on the condition of the supporting structures such as columns and the visible framing overhead. Columns: Posts and columns are vertical supports that carry the weight of the structure from the girders (or beams) to the ground. Columns transmit the weight to footings below. It is not unusual to find columns or posts put in to support an unusually heavy load such as a piano. These are ancillary supports which need to be evaluated for structural integrity as well. As per the standards of practice, the inspector needs to identify the materials used in column construction – steel, wood, or masonry. Columns should be inspected for their condition and ability to support the structure above.
The inspector will determine if the column or post is doing a proper job of supporting the structure above:
Inspectors may see shims of metal or hardwood inserted between the beam and column. The shim should be large enough to cover the interface between the beam and column. If it’s too small, the beam or top of the column may be crushed. The inspector will report on damaged or crushed shims.
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 Typical joist and ledger configuration
Water damage to sill and truss |
Joints are horizontal members of a floor system that carry the weight of the floor to the foundation, girders, or load-bearing walls. Joists are supposed by the beams or girders as described in Girders. They meet the foundation wall, either resting on and nailed to the sill and header or resting on the foundation. Joists are generally2x wood; however, they can be in the form of wood trusses, engineered lumber or metal. In conventional construction – 2 x 8’s, 2 x 10’s, or 2 x 12’s, placed on 12 - 24” centers. Typically 16” centers is common. The allowable span for joists can vary considerably, depending on the material used. For example, a 2 x 8 joist of Douglas fir or yellow pine can safely span 12’, but if made spruce, redwood, or white fir only 10’. The inspector is usually unable to determine proper span without knowing the type of wood and is limited instead to determining the condition of the joist. They look for deterioration and wood rot, cracking, twisting, sags, and loss of bearing. The allowable span for engineered lumber also varies depending upon manufacturer. Allowable spans for this material are 12”, 16”, 19.2”, and 24” centers. Joists should be reinforced (double or triple) under a partition. Other areas such as around stairway openings are reinforced with double or triple headers running perpendicular to the joist; for wide openings the joists themselves are doubled. Often a bracing, system is used between joists to add stiffness to the joists and keep them from twisting. Building codes vary from area to area on how blocking or bridging may be done.
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 Termite damage to sill and joist
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The sill sometimes called the sill plate is the portion of the framework that sits directly on the foundation and provides a pad for the bottom of the framing system. Sills today are generally 2x6 or 2x8 treated lumber laid flat on the foundation and anchored in place with bolts or other approved strapping material. The sills in older construction most likely will not be treated wood; however, some type of moisture barrier is installed between the sill and the foundation. Wood sills support wood framing members, but not masonry, which sits directly on the foundation. The header, band or rim joist, is nailed to the sill plate. Home inspectors inspect the sill and header for rot. This can be caused by a defect in the siding, from soil too high around the exterior of the house, or water wicking up through the foundation. Suspicious wood is generally probed with a screwdriver to check the integrity of the sill or header. In cold climates, a pad under the sill consisting of mortar is packed against the sill. In some properties, the sills may be covered with insulation. If this is the case, the sill and headers may not be visible and are not evaluated. However, problematic areas such as door entrances are checked. A sill over the window opening may sag or break from stress without a lintel or header having been installed underneath. This should be pointed out to the customer.
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 Improperly cut floor joist
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Rule #1: Mid-notches – Where a notch is cut into a beam along its length – should be no deeper than 1/6 the depth of the beam. A mid-notch is allowable only at the top of the beam, not at its bottom. And the notch shouldn’t be cut in the middle 1/3 of the beam’s length. Rule #2: End notches cut into beams – where the end of the beam rests on the foundation, sill, or pier – can be no more than ¼ the depth of the beam. Add as mentioned on the previous page, the beam resting on the foundation wall or prier should have 3” to 4” of beam resting on the end supports. Rule #3: Holes cut into beams should be no more than 1/3 the depth of the beam. Holes should not be cut into the top or bottom 2” of the beam. Rule #4: Girder-like trusses should not be cut into at all or have any parts of the truss removed. The strength of the truss depends on the relationship of all of its parts to each other, and integrity can be lost by cutting or removing any part. Trusses are also inspected for loose or rusted fastenings. Girders and joists are carefully inspected for any violation of the above rules. Often heating contractors, plumbers, and electricians, who come in to work on finished houses, are the worst offenders when it comes to improper notching and cutting of framing members. As a home inspector, I often see evidence of their work. In the picture to the left, the plumbing contactor cut the floor joist in order to run his plumbing chase. No additional support was given to the framing member.
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