Website design By BotEap.comIn a recent safety assessment of residential decks in and around Charlottesville Virginia, an alarming trend was observed. 7 out of 10 decks had at least one safety problem, and 4 of the decks had significant safety problems that were cause for immediate action. Most homeowners hire a contractor to build the deck or the deck was attached to the home when the home was purchased. Some of the most serious problems encountered were:
- Insufficient methods of attachment to the home.
- Inadequate fixation of the beam
- Insufficient lateral reinforcements
- Wrong or missing attachment
- Undersized frame members
- Inappropriate bras worn
Website design By BotEap.comThe most serious problem, insufficient attachment to the house, was found in almost half, 4 out of 10, of the roofs inspected. When a ledger board or band board (the member of the deck frame that is attached to the house frame, to which the deck beams are attached) is attached to the house incorrectly, the platform is a critical risk of collapse. . Wood planks MUST be fastened to the home with lag bolts that are securely attached to the edge joist or home frame, or carriage bolts that fully penetrate the home frame and are secured with a washer and nut on the other side. The issues we saw included the use of no more than 16 penny nails, lag screws that bypassed members of the house’s frame and attached only to the exterior siding (plywood), and, in a box, wood screws standard. Improper clamping techniques and materials are the leading cause of deck collapse, resulting in injury and death. When using a platform for entertainment, the change in load as people move on the platform also modifies the stresses on the platform structure. The more people, the more weight and the greater the forces involved. One of the covers we inspected was so poorly constructed that the weight of one person was enough to cause the cover to rock slightly. Put 20 people on that platform, and they’re all at risk.
Website design By BotEap.com16 cent nails are not thick enough to support heavy loads and have too little force to resist lateral forces to resist pull. Any adult can pull a nail with a hammer claw using as much force as the force of 30 pounds of weight. Put 20 people, weighing more than 2,000 pounds, on a nailed platform and you will see the problem. Nailing, screwing, or even bolting the siding of the house is essentially useless. Most siding products are less than 1/2 inch thick. They are designed to provide lateral (lateral) strength to a structure, not to resist pullout forces. The best method of attachment is to use carriage bolts that go completely through the deck band board, through the house band board or other member of the structure, and are secured with a washer and nut on the other side. When this is not possible, lag screws should be used and secured to members of the house frame.
Website design By BotEap.comThe next serious problem observed was found with the attachment of the deck beams to the deck strap board. Again, on nearly half of the covers inspected, the joists were simply toe-nailed to the band board and / or toe-nailed and set into a 2X2-inch support block placed under the joist. The same problems of low pull-out strength and load-carrying capacity apply here. The only correct way to fasten the deck beams is to use a metal beam hanger. They are designed to withstand the load and withstand lateral forces when used correctly. Look under your deck. If you don’t see the beam hangars, nailed 90 degrees to the deck band board and beam, your deck is not safe!
Website design By BotEap.comMost of the decks inspected used 4X4 treated wood posts that were buried in the ground below the frost line and set on a suitable concrete base. Some of them were not. Two of the decks had 4×4 posts literally just resting on the concrete, without any method of attachment to the concrete. If you are not going to bury the post at least 2 feet below ground level, you must use a metal post base bracket. The base of the post was attached to the concrete using the appropriate concrete fasteners, then the post is attached to the support using nails to hang the studs or lag screws.
Website design By BotEap.comSubsequently, a serious lack of lateral bracing was observed on most of the roofs. Lateral bracing prevents the deck structure from shifting sideways. If you were to start by taking a few steps in one direction on your platform and came to a sudden stop with force, your platform should NOT MOVE. If it does, it is not properly reinforced. Your deck should be at least as strong as the floor inside your home and often stronger. The siding of your home frame provides the lateral reinforcement. In a deck, it should be made of dimensional lumber that is designed to withstand exposure to the elements. When properly planned, the lateral bracing of a deck can be incorporated into the design in a way that adds to the appearance of the deck while providing a structural purpose. If your deck is built on a slope, or less than 24 inches above grade, it will be necessary to apply lateral bracing before laying the deck surface. On decks more than 24 inches above ground level, an angled piece of dimensional lumber should be fastened to each side of each post, from the top of the post to some point below the top, with a minimal angle. 30 degrees. If you have a deck, have a professional inspect it immediately. An inspection should take about an hour and cost less than a hundred dollars if you call a contractor. A small price to pay for your peace of mind.
