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How to Build a Patio Deck

Building a patio deck can be a fun and rewarding project but don't underestimate the cost or the difficulty level of this project. While any two people can build a deck, it pays to start out with the concept that this is a somewhat complex process.

Planning

Before you build your deck you should have at least a rough sketch, but preferably a blueprint of how it will look. You can buy deck plans on-line very reasonably or you can custom design your deck.

The first step of planning is to decide what size and shape you want your deck to be. Unless you are an experienced carpenter, square or rectangular is recommended for your first deck building project. For a rectangular deck measure the back of your home to see how far you want your deck to run along your wall, and how far you want it to extend into your yard.

Eight feet is a good width because it prevents having to cut the joists. Likewise multiples of 8 or at least multiples of four for the length, keeps cutting and waste to a minimum.

You may need to speak to a building inspector about your project, especially if you live in town. It's a good idea to talk to someone with experience to get pointers on the depth of footings in your area.

Labor

It takes at least two people to build a deck, but more than five can cause confusion. Two people are needed to handle both ends of long boards, while actually building the deck. A third person can be used to cut the lumber, and fetch tools. A fourth and fifth person can help each of the carpenters building the deck. It is very helpful if at least one person is a carpenter, or has at least built a deck before. It is possible to build a deck if no one present has built one before, provided they can follow directions, and have studied how to articles like this one. It's best to keep instructions handy, and look up any questions on the internet. Never guess.

Materials List

Use your plans to decide how much you will need of the following.FlashingConcrete mixCardboard construction tubesGravelPost basesJoist hangersDeck screwsLag bolts, nuts and washersWooden or synthetic boards for deckingTwo by eight inch or two by 12 joists for supportsSix by six pressure treated posts to hold up the deck.

Equipment and Equipment Rental

Shovel and post hole digger or rent an auger
Carpenter's level and square
Wheelbarrow
Drill
WrenchHammer
Circular saw
Tape measure

Safety Tips

Always be aware of your tools, and their cords.

When using a circular saw, keep your fingers well clear of the blade and the cord behind the saw, not near the blade.

Always cut lumber on a steady surface. Never just prop it up on something to cut with a circular saw.

Take your time and avoid any rushing around.

Do not use alcohol and a circular saw at the same time.

If the deck will be high off the ground use a piece of plywood to stand on while installing decking boards, to avoid standing on joists.

Step By Step

Footings

1. Measure carefully to determine where posts should be. Mark each area. Depending on your location you should dig a hole from two feet to four feet into the ground at each post location.

2. Insert a cardboard construction tube into the hole and cut off the excess about two or three inches above the ground. Make sure each tube is perfectly level and straight.

It pays to measure carefully to insure that the line of footing is straight, level and parallel with the wall

The hole depths will almost certainly vary a bit, and the ground may not be perfectly level so you will need to run a straight board to lay across the tops of the concrete forms, to insure that they are in line with each other.

Place a level on the board to make sure forms are even in height. Insure by measuring in every way possible that the concrete footings will be parallel to the wall of the house, level with each other and in a straight line.

3. Fill in the area around the tube with soil and possibly some gravel. Wet it slowly and tamp it down to secure the earth tightly around the tube, which will serve as your concrete form.

4. Mix the cement in a cement mixer to peanut butter consistency and pour it into the tubes to form the footings.

5. While cement is still wet, insert the bolt which fits the metal post base hardware. Again insure that these bolts are in a straight line with each other in the center of each footing.

Posts, Sill Plate and Joists

6. Remove the bottom one or two strips of siding if necessary, and attach the flashing to the bottom of the wall. Nail or screw a 2 x 8 piece of lumber across the bottom of the wall and over the flashing, so that the top is one decking board thickness or a bit more below the door.

7. You will need to take a break for a few days in order for the concrete to cure. If this is a weekend project, do this job the weekend prior to building the deck.

8. When the cement is dry (days later) attach the post base hardware to the screw bolt sticking out of each footing. This post base prevents the wood from touching the metal, and holds the post straight.

9. Cut the posts to the correct height, first insuring that the footings are still level. If they are not, you can correct the difference by varying the height of the posts to compensate. You will want these posts to come up to the height of the railing, not just the height of the deck.

10. Insert each deck post. Into the appropriate base and attach firmly with screws. Use your level to insure that they stand perfectly straight.

11. Once the posts are in place, attach a 2 x 8 board across all of them at the same level as the one attached to the house. Test this by placing a board spanning from the board on the house to the board running across the post. Put a level on the spanning board and gradually slide it down the row, checking every few inches to make sure it is level. Adjust the boards accordingly.

12. Place a double thickness of two 2 by 8 boards directly under the top board for support. Be sure that the two lower boards are completely tight and flush with the top board with no gaps. If you prefer you can use metal joist fasteners.

13. Attach joist fasteners, about 14 inches on center from each other, all the way across the board on the house, and even with the 2 by 8 boards on both sides. Run your floor joists across the span between the fasteners and the board you placed so that they are resting on the double thickness bottom boards and even with the top board.

14. Insure that the joists are level, both with each other, and from front to back, then nail them in place one by one. Checking the level each time.

Decking, Railing and Stain

15. Once the joists are in place, cover them with the decking boards you chose. Be sure to leave an even amount of space between each board.

The best idea is to get a thin piece of ply wood, about 8 foot long, and one quarter inch thick and maybe four or six inches wide, and slipping it between the boards before nailing them in place. Then Remove.

Most carpenters just insert a carpenter's pencil between boards, but for beginners the longer guide helps to keep it even. It is necessary to leave a gap between the boards to allow for drainage and expansion.

16. Attach the railings, to the tops of the support posts.

17. Treat your deck with a top brand deck sealer, an appropriate stain or paint to prevent rotting or warping. From now on you should treat your deck annually to protect it.

Building a deck can be fun, but it is hard work, and it is important to remember safety first. Expect to get a few bruises, splinters or scratches during this procedure, but be careful of the auger, saw and drill to prevent more serious injuries. Enjoy building your deck and using it.

You can buy deck plans online or you can custom design your deck