The connection at the house must be detailed carefully�CAttaching a deck to a house is risky business. Screwing or bolting into a house opens the siding's protective envelope to moisture. which can lead to decay and insect Drawings: Vince Babak attack. Wherever practical, it's best to build a freestanding deck. If a freestanding deck isn't feasible, take extra care attaching the deck to the house. patio flooring options over concreteAnd although it probably goes without saying, nails aren't adequate to make this connection. To prevent water from entering the house, it's important to caulk pilot holes in the band joist of the house before installing screws or bolts. It's also prudent to add spacers, such as a few washers. between the two structures to allow the gap between the deck and the house to dry. You also should extend metal flashing under the siding above the deck and over the siding below the deck (drawing p. 64). If the deck is attached to the house, it may be necessary to reinforce the band joist of the house to resist lateral forces that tend to pull the deck from the house.

Sixteen-d nails at 8 in. o.c. that are driven through the sole plates and mudsills, from above and from below, add sup port to the band joist in new construction. It may also help to provide additional bracing on the deck: however. our recommendation to reinforce the band joist highlights the need to transfer adequately the deck loads to the house framing. There have been cases where the deck was firmly attached to the band joist, but the band joist was not secured to resist the deck loads and was ripped from the house when the deck failed. Of course. we recommend X-bracing between the posts for freestanding decks. outside flooring materialsThis topic is covered in our deck manual in more detail (Wood Decks: Materials, Construction, and Finishing, published by The Forest Products Society; 608-231-1361). Proper size and spacing of fasteners is critical�Cwherever you use bolts in a deck. the strength of the connection depends on the correct size and spacing of the fastenen. To attach decks to the band joist of a house, where you use 12-in., 16-in. or 24-in. joist spacing, two 3 /8 -in. dia. lag screws are needed every 24 in. for a 6-ft. span. Two 1 /2 -in. dia. lag screws are needed every 24 in.

for spans of 6 ft. to 16 ft. Don't skimp on fasteners��The two most important things to remember when choosing deck fasteners-framing nails, decking nails. screws, joist hangers. bolts and lags-are their holding capacity and their resistance to corrosion. Inadequate fasteners or improperly installed fasteners can cause connections to loosen, and when they corrode, they weaken the surrounding wood. Most fasteners are made of mild steel or stainless steel and are produced in a variety of styles. Protective coatings are often applied to mild steel fasteners. Stainless-steel fasteners last the longest, followed by hot-dipped galvanized-steel Stainless steel lasts longer. The nails on the right side of each pair were nailed into solid-wood blocks and subjected to 14 years of exposure to high humidity.outdoor deck railing Screws have advantages over nails: They are effective in drawing down cupped or twisted decking, and they can easily be removed. For screws, the length recommendations given previously apply. A word of warning about multipurpose screws, however: They are not intended to fasten joist hangers. Use only manufacturer-specified hanger nails to attach joist hangers.