Planning a home improvement project? Arizona Department of Weights & Measures wants you to know about some method of sale requirements and measuring techniques that can save you both time and money, especially if your project requires lumber or flooring material.
In Arizona, method of sale requirements for softwood lumber are incorporated by reference from the standards created by the American Lumber Standard Committee (ALSC), adopted by the National Conference on Weights and Measures and published by the US Department of Commerce. These standards allow soft lumber, commonly known in the building trade as a 2 x 4, to be labeled using the "Nominal sizes" method. "Nominal sizes" were originally derived from the dimensions of rough lumber before surfacing, and are always greater than the actual dimensions; thus a dry "2 x 4" is surfaced to actual dimensions of 1-1/2 inches x 3-1/2 inches (38 mm x 89 mm). In other words, nominal sizes are size designations used for convenience in describing approximate, rather than actual size.
"A ½ inch measurement difference can wreak havoc on a project if you are not aware of it, so it is always wise to measure twice and cut once. Shoppers should keep in mind that the use of nominal dimensions is allowed if the actual dimensions are prominently displayed to the customer, and the term "nominal" or "nom" is used in conjunction with any representation of nominal dimensions," advises Art Macias, Director of the Arizona Department of Weights & Measures.
With this in mind, home improvers should use the following "common sense" measuring tips:
- Measure Twice Cut Once. Standards allow lumber to be labeled as much as ½ inch smaller in both thickness and width.
- Look straight down when measuring. If you look at an angle you won't get an accurate measurement.
- Use the same measuring tape. Different tapes will give you different measurements. This is because the tips of the tapes will have differing amounts of play in them. For the most accurate measurements, start at an inch and measure, subtracting an inch from your final total.
Measurement of Flooring Materials
If you are planning to replace or install flooring, the following guidelines will help you with your buying decisions. Flooring such as tile and carpet are sold by and measured in square feet. It doesn't matter if the tile is 12"x12", 13"x13", or 18"x18" it is sold by the square foot, not by the piece. However, tile trim may be sold by the piece. The square footage of tile includes the width of the recommended grout line between the tiles so a 12" x 12" tile may be smaller than 12".
To help you determine the amount of material you will need, remember that a square foot is 12" x 12" or 144 square inches. To determine how many pieces of trim you need, measure the total linear inches to complete your project and divide by the length of the trim piece (if you measure in feet, don't forget to multiply by 12 first to convert to inches). To determine the amount of material you will need when measuring floors, multiply length x width. If you are measuring a wall, multiply length x height. For example, if you have a floor that is 10 feet by 21 feet, the area in square feet is 210 (10x21). If a room measures 200 square feet, you need 200 square feet of tile plus a factor for cutting, waste, breakage, and a supply for future use. Remember--if installing tile in a square pattern, add 7% to your exact measurements. If you are installing tile on a diagonal, add 10% to your exact measurements.
Final tip: Use the same measuring tape for accuracy, take exact measurements, rounding up to the nearest 1/8 inch. Start with the width and then measure the length. When sketching out your plan, be sure you correctly label which is width and length.