Attaching rafters to beams
There are various ways of attaching rafters to a beam. The most common method of fastening them to the top of a beam is to drive in screws at an angle.

When doing this, it may be necessary to drill pilot holes first so the wood doesn't split. If the rafters will slope, use seismic anchors (also known as rafter ties), as shown at right.

Although one standard anchor is adequate in most cases, a second one may be required diagonally across from the first one in high- wind or seismic areas; consult your local building department for standards in your area. With conventional anchors, you must notch the rafters to fit or use a double-sided anchor to avoid notching.

Bracing rafters
Where rafters span long distances or are spaced wide apart, they are prone to twist or buckle unless braced with blocking. The width of the rafters is also a consideration; those made from 2 by 8s or larger lumber require more blocking than those made from 2 by 6s.

Spacing between blocking is typically determined by local codes. If rafter spans are less than 8 feet, headers (perpendicular rafters) nailed across the rafter ends are adequate for rafters that sit on top of beams.

Snap a chalk line across the rafters where the blocking will go, and then work your way across the joists, measuring and notating the lengths of blocking you'll need.

The easiest method of placing the blocks is to stagger them from one side of the chalk line to the other, as shown below. By using this technique, you'll be able to face-nail the blocks instead of toenailing them. Use 16d nails.

For a decorative accent and to hide metal post caps, you can cut and miter trim stock to fit around the post tops.




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