How to Build that Deck.hubpages.com
It is almost a given that your home will have exterior “add-ons” like porches and decks, so we must take a moment and touch on them or we would be negligent in our considerations. The most common type of exterior extension is a wood deck. Though there are many new decking products on the market, pressure treated lumber appears to be the most popular. Decks have many different styles and construction types so it would be impossible to cover every aspect in this article without adding many additional pages, so let’s look at some of the most common errors. One very common framing mistake made with the installation of a wood deck is how the deck is fastened to the home. This is one of the most neglected areas of construction, mostly from inadequate fastening of the deck plate. By not properly fastening the deck securely to the box beam or the foundation the deck is at risk of failing. Many decks have collapsed because of inadequate support at the house attachment or improper lag bolts being used. It is very hard sometimes for the Code Official to catch whether a proper length lag bolt has been used, or if the bolt has actually fastened into something solid. Don’t forget that in prefabricated floor systems the box beam may only be a ¾” piece of plywood, not capable of supporting a deck. Proper lag bolting, preferably staggered to prevent the deck board from splitting, is crucial to a solid construction. I have seen decks fall from a second story because the nails used to hold the deck into place had rusted and weakened causing them to pull out or shear off. Never should nails alone be used to fasten a deck to a house, and always make sure the lag bolting is fastening into something acceptable and not just plywood. This intersection where the joists meet the deck plate usually requires the use of a fastening device for each joist, such as a joist hanger. Sometimes you may see a ledger board notched to the bottom of the joists used instead, but most of the time a joist hanger is used. Proper nailing can be crucial to the use of these devices so you must follow the manufactures recommendations when installing them. There may also be special nails needed for the installation. Never use a screw in place of the nail unless it is specifically designed for this purpose, a screw will not have the required shear strength to withstand the load and may shear off when under pressure.
The other crucial area for deck construction is the footings to support the deck. In most cases of failure or settling, the footings have been affected by frost penetration because of improper depth. For areas where the ground is subject to frost penetration a footing must be designed to prevent damage. Most Building Codes will require a certain depth depending on the area that you live in so check with the local Code Official before starting. The footing must also be designed to properly support the load that will be imposed upon it. A design professional can assist with this part of the project to assure that your deck is properly constructed. I once witnessed a deck collapse that could have been prevented if the deck was properly fastened to the house, and the footings had been properly erected. Over 30 people were injured when the deck fell to the ground and it all could have been avoided if properly constructed. Oh by the way, the deck was erected without a building permit.
There are other decking materials that can be used that are manufactured products. Be careful to note the heaviness of some of the products since the framing is required to be increased to support the additional load. Again, if you have any questions about the proper construction of your deck feel free to contact both your local Code Official and your Design Professional. Don’t forget about some other wood options that can be used like cedar, but whatever you decide to use always know both the advantages and the limitations of the materials, and please consult the local Code Enforcement Officer before starting.
Taken from "How to Build a Deck from "A" to "Z" found at amazon.com or createspace.com