Gomputer software eases metrication

IfOW

the January 1994 deadline

Ilfor instituting the use of metric in the design of all federal construction will affect our industry concerns some, but as computer-aided design and drafting systems continue to increase, switching between the inchpound system and the metric system can be simpler. Metric conversion, CAD and engineering software also is available.

About 95Vo of. the building products will not change because they are not modular or panelized. Many products will be relabeled in metric. For example, a 4-112" wall switch faceplate will be relabeled 70 x 115 mm. BOCA, SBCCI and NFiPA and ASTM standards already use both inch-pound and metric measurements. Other organizations have added metric measurements o their standards or are in the process of doing so. The wood industry has shipped exports in metric for many years.

Use of metric will eliminate fractions, inches and feet in building products. All measurements will be in millimeters. Field measurements can be faster with less chance for error since unit conversions are not necessary.

One millimeter (mm) is about 1/25 inch or slightly less than the thickness of a dime. One meter is the length of a yardstick plus about 3-113 inches. One inch is a fraction (1/64 inch) longer than 25 mm. One foot is about 3/16 inch longer than 300 mm.

The Construction Metrication Council of the National Institute of Building Sciences, Washington, D.C., has listed some of the changes applying to building products.

Spacing for 2x4 studs and other 2x framing, both wood and metal, will change from 16" to 400 mm (about a quarter of an inch closer) and 24" to 600 mm. Cross sections will stay the same and 2x4s may keep their nominal name or be relabeled a nominal 50x100 nm or more exact size.

Engineered lumber products won't change sizes (a 24" I-beam has no acfinl Vl" dimension), but will be relabeled. New nominal names such as 600 mm beams are possible.

Drywall, plywood and rigid insulation widths will change from 4'0" to 1200 mm, height ftom 8'0" to 2400 mm, l0'0" to 3000 mm. Thickness will stay the same so fire, acoustic and thermal ratings won't have to be recalculated. Metric drywall is already available.

Batt insulation will change from 16" and 24" nominal width to 4(X) mm and 600 mm nominal m not change to be used with more of a "friction fit."

Thiclcress will stay the sane to avoid recalculating themral ratings.

Doors will change from 6'8" in height to 2050 or 2100 mm and 7'0" to 2100 mm. Widths will change from 2'6" to 750 mm, 2'8" to 800 mm, 2'10" to 850 mm, 3'0" to 900 or 950 mm, 34" to 1000 mm. Thiclmess and door materials and hardware will remain the same.

Ceiling grids and lay-in ceiling tile, air diffusers and lighting fixtures will change from 2'x2' to 600x600 mm and 2'x4' to 600x1200 mn. Grid profiles, tile thiclnesses, air diffuser capacities, fluorescent tubes and means of suspension will remain the same.

Raised floor system grids and layin floor tile will change from 2'x2'to 600x600 mm. Grid profiles, tile thickness and means of support will remain the same.

Dual unit tape measures will be needed for most job site work. They are available from many manufacturers including Stanley Tools, Lufkin and U.S. Tape.

Metric Information Sources

PLANNING

Amerlcan Forest & Paper Assn.

1250 Connecticut Ave. N.W. Washington, D.C. 20036 (nD463-27N

SOFTWARE

Advantage Buslness Computer Rt. 2, Box 879 Big Sandy, Tx.75755 (8O0) 452-2502

Allgeler Computer Corp. 3fl)2 Dow Ave. Suite 116 Tustin, Ca.92680 (800) 5244396

CSD

12130 Pennsylvania St. Denver, Co.80241 (800) 688-9606

Datallne 43 Danburv Rd. Wilton, Ct.'OOASZ (800)723-3676

Dinenslons

5500 Amelia Earhart Dr. Salt Lake City, Ut. 84116 (800) 648-5065

MCB Enterprlses Box 6563 Huntington Beach, Ca. 92615 (7r4\ 647-ss34

Oflice Equipment Co. 125 Oakway Center Eugene, Or. 97,101 (503)342-3325

Orlon Development Corp. Box2323 Merrifield, Ya,.221L6 (80o) 992-8170

Versyss 4fi) Blue Hill Dr. Westwood, Ma.02090 (800) 899-6400

Vldtrack Technologles Co. 540 S. Main St, Suite 941 Akron, Oh. 4431 1 (216)762-sr4r

STANDARDS

Natlonal Partlcleboard Assn. 18928 Premiere Ct. Gaithersburg, Md. 20879 (301) 670-0604

Hardwood Plywood Mfrs. Assn. Box 2789 Reston, Ya.22090 (703\ 435-2900

Videotapes

Workplace Tralnlng 520N. AImDr. Orono. Mn.55364 (612) 472-2s64