The National Design Specification for Wood Construction contains design provisions and design values for wood screws that conform to ANSI/ASME Standard B18.6.1. When wood screws are loaded in withdrawal, the design value for tension in the screws should not be exceeded. For single-shear wood-to-wood construction, the screws should be inserted in the side grain of the main member with axis perpendicular to the wood fibers. Edge and end distances and spacing of wood screws should be sufficient to prevent splitting of the wood. If building-code requirements for such distances are not available, Table 10.38 may be used to establish wood-screw patterns. Spacing, or pitch, between fasteners in a row is affected by species, moisture content, and grain orientation. Screws may be inserted in lumber or timber that has a specific gravity less than 0.50, without preboring a hole for them. In denser wood, lead holes should be drilled and screws inserted by turning, not by hammering. Holes for wood screws loaded in withdrawal should have a diameter of 90% of the screw root diameter in TABLE 10.37 Minimum Edge and End Distances, Spacing, and Geometry Factors C for Split-Ring and Shear-Plate Connectors 21/2-in Split-ring connectors 25/8-in Shear-plate connectors

In the training workshop we are most likely to use a steel square to set out our brickwork. Care and accuracy are once again the main requirements. Having set out and laid our first course as already described, we place one leg of the steel square against the face of the first course to create an accurate angle for our return to follow. After we have laid our return bricks we need to ensure that they are level. Always level from the corner point to the end of the course you are laying. This applies to each course we lay as we build our quoin to the intended height. Laying and levelling from the corner point maintains accuracy. If we keep in mind the sequence already mentioned for building a brick rack, we can speed up our work rate and add to our efficiency. Remember: gauge level plumb line. Lets review some techniques that help us maintain quality and standards. Keep in mind that the spirit level is a precision instrument. Never strike the spirit level to align bricks horizontally.

There are three main types of wastewater: domestic, storm, and industrial. Separate plumbing systems are generally required for each type. Domestic wastewater is primarily spent water from the building water supply, to which is added wastes from bathrooms, kitchens, and laundries. It generally can be disposed of by discharge into a municipal sanitary sewer, if one is available. TABLE 14.6 Hot-Water Demand per Fixture for Various Building Types* [Based on average conditions for the building type, gal /h of water per fixture at 140
F (60
C)] Apartment buildings Gymnasiums Hospitals Hotels Industrial plants Office buildings Dwellings Schools Lavatory, private 2 2 2 2 2 2 2 2 Lavatory, public 4 8 6 8 12 6 15 Bathtubs 20 30 20 20 20 Dishwashers 15 50 50 20 15 20 Foot basins 3 12 3 3 12 3 3 Kitchen sink 10 20 30 20 20 10 20 Laundry, stationary tubs 20 28 28 20 Pantry sink 5 10 10 10 5 10 Showers 30 225 75 75 225 30 30 225 Service sink 20 20 30 20 20 15 20 Hydrotherapeutic showers 400