Planning and Preparing for a New Deck
Installing a deck is easier with some help. Ensure that your chosen design follows any homeowner association rules for your neighborhood. Typically you will be required to submit plans of the proposed deck for review by an official.
Check with your building code office before constructing a deck. Regulations regarding steps and railings are similar to those for staircases. If you are building a large or very high deck, get professional advice on footing and lumber specifications.
Generally, the higher the decking is off the ground, the deeper the foundations need to be. For ground-level decking, you will still need to go below the frost line.
Ground level decks require posts set into the ground to prevent slippage, movement or sinking from forces like erosion and to accommodate slightly un-even terrain. Set posts in all four corners of your deck and according to local rules.
Post holes should be at least 24 inches deep and must extend below the frost line. On a concrete surface, use bolt-down post anchors. When building a large deck, or one raised by more than 24 inches, get professional advice on lumber and footing specifications.
Lumber for decking that contacts the ground must be pressure-treated and any cut ends must be treated with preservative. Plan the support layout on paper so that you can work out how much lumber you need to buy.
Deck shape can be easily adjusted to any requirement with minimal woodworking skills. The decking boards themselves can be straight, run diagonally, or you can create more complex chevron or square designs. Trim edges with a power saw to create curves. You may need to use double joists to enable you to fix more complex designs.
Where you want a curved edge to a deck, run the framework in steps around the curve. Use a pencil and string tied to a nail to draw a smooth curve across the boards (image 1). Use a jigsaw to cut around the edges of the boards. Treat the cut ends with preservative (image 2).
Even small-scale decks are governed by regulations. Check with your building inspector that you have sufficient supports for the size of deck.
Newel posts need to be at least 36 inches high and support the balustrade at least every 6 feet. Railings are mandatory if the deck is over 20 inches off the ground.
The frame for raised decking is constructed from pressure-treated lumber. On a concrete base, posts can be secured to the ground using bolt-down post brackets; on soft ground, some excavation work is required to bed the posts securely on a solid foundation. Take time to remove vegetation and put down a membrane and gravel beneath a deck on soft ground, as for a gravel path. A raised deck requires a handrail.
Decking boards are usually run parallel to the house, across joists. While this is a fairly standard approach, there are other custom options for running boards. Shown here (image 1), the composite boards are mitered at the end, creating a square pattern on the deck.
Decks can dramatically change the appearance of your backyard, creating an “outdoor room” that’s a perfect place for barbecues and a safe outside place for toddlers to play. Not only do you need to select the structural materials, and the decking type, there are post options and caps that can add style and personalize your deck. From natural wood options to synthetic materials, there is a type of decking that will complement your home’s design.
Railing material is offered in as many types of materials as decking boards. Most often, railing material is chosen to match the decking boards, although mixing materials is an opportunity to showcase a unique design—wooden boards and polyurethane balusters have been combined here (image 2). When selecting material for rails, make sure to plan for enough pieces and parts so your deck follows your local codes. In most areas, the local codes for railings and stairs follow the same criteria as interior railings and stairs.
Seal every two years. Use a cedar decking cleaning product or restorer. Hose down. Do not pressure-wash.
Can warp, spilt and splinter over time. Pressure-wash or hose down. Seal every two years.
Weathers to a lighter tone. Requires no annual sealing. Pressure-wash or hose down. Composite deck-cleaning products are available.
Resists cracking and fading. Requires no annual sealing. Needs a monthly hose-down.
Choosing a product to seal your wood deck is not as easy as you may think. Some deck sealers contain natural oils that are food for mildew and algae, and even good deck sealers may not be able to penetrate your wood deck if you have used a bleach product or a deck cleaning product that contains bleach. When you are selecting a sealer, make sure you use a heavy-duty synthetic deck sealer that is water-repellent, and not just an exterior wood sealer. Before using any sealer or cleaner on your deck, test a small portion of the material to see how it reacts to the product.
Mixing wood species can create a striking deck design. Combining light and dark woods gives you the opportunity to create patterns and accents. Deck accessories are another great way to match your chosen decking material to the furnishings on your deck. You can use extra material after you've finished the deck building project to build benches and flower boxes, for example.