By Lee McGinley. The romance of hand-cutting rafters for an addition's roof quickly evaporates when you're boosting 2x12s into place. It's up and over the double plate, then hand-over-hand up staging and ladder to the ridge, while someone else makes sure the bird's mouth fits just so.
There's no question that manufactured roof trusses make roof framing easier. However, spacing them 24 inches on center and holding them in place until you nail on the sheathing requires temporary wood bracing, which is then removed prior to sheathing. That all takes extra time and materials. (Not to mention time and labor lost should you have an inaccurate layout.)
Here are three "space-and-brace" metal products that could save you on that time and materials. The first two have dual functions: They provide 24-inch spacing while setting trusses and, because of their low profile, you can sheath right over them. You'll still have to nail a strong back to the gable end to plumb and secure the first truss, but setting the remaining trusses should be easier and more accurate.
MiTek's Stabilizer ( www.mii.com) has side flanges, which bump against the top chords of adjacent trusses to assure proper spacing. You hammer pre-punched teeth on the top flap into the top chord, then bang in teeth on the side flanges. MiTek claims that with its product, hip ends can be pre-assembled on the ground before they're lifted into place with a crane.
MiTek's Hinge Plate technology is for remodelers who have wrestled with piggyback trusses, as I have. The Hinge Plate technology eliminates the cap truss and associated rows of 2x bracing between the cap and the bottom truss.
Simpson's Truss Spacer Bracer ( www.strongtie.com) installs with nails, rather than prongs, and captures each truss by slipping over the chords. The 1/16-inch "slop" in each end compensates for thicker 2x stock and allows the installer to reduce creep.
Both the MiTek and Simpson products sell for about $1.50 per spacer.
These products won't eliminate diagonal or cross bracing. You'll still have to abide by the manufacturer spec sheets for proper bracing. But with any of these products, brace yourself for some labor savings.
– Lee McGinley, CR, a Big 50 remodeler, has written for THE JOURNAL OF LIGHT CONSTRUCTION. He lives in Addison, Vt.