Deck: How To Build A Deck

Building a deck is very easy. You can build one attached to the house or a free standing one. If you decide to build a free standing one then you can actually build a gazebo, or even apply the method to build a storage unit. However, you will need to know how to build a foundation deck so read on here.

Most folks I know wanted to turn their deck in a screen room, and some actually wanted to even convert it into an extension to the house. So I will show you how to build it solid like a foundation. This may add up to 20% on your cost but beats having to take it apart to pursue your next building ambition.

Before embarking on any building plans, be sure to check with your local government for any applicable ordinances and or codes.

Check the area where you want to build your deck. Normally, it is patio area you enter through sliding glass door. This door is only 4 inches above ground level. Therefore you will need to build a step up deck. This can be 7inches to up to 19 inches high from the ground and a stair may be needed to get up on it when you exit the house onto the deck. You can actually make it into a multilevel deck by adjusting the height of your joists for that portion like an amphitheater.

If you build the deck here, the reason you are going 7inches high is because when it rains you do not want it to splash such that it goes under the house siding and you are not going above 18 inches cause you don't want the splash to come through the window if you have one. Apart from that work on your imagination, if you dream it you can build it.

The deck we are going to build is 12 feet by 22 feet. You will need to adjust the materials for the deck size that you will build. I picked a location outside my kitchen and dining room which was below my bedroom. The ground dropped a good 18 inches just outside the breakfast nook area of the kitchen where there is a window. It went slightly up hill from there so the ground level from the dinning window side was barely 7 inches drop from top of the concrete slab of the house. I will cover replacing windows with doors in another DIY, so for now let us build the deck.

Two things you need to know at this point. One you are going to convert this deck into a room at some point in time. To do that you will cover the deck with a ¾ inch ply, which will become your floor at that time. This floor has to be level with the slab of your house right? So your finished deck needs to be ¾ inch below the slab level.

Secondly, to build a room on top you need beams which will support your load bearing wall. Load bearing wall depends on how you will do the roof. Since, there were several different ways I could do the roof I decided to put down the beams on three sides. Don't get scarred with fancy names. A beam is an extra piece of 2x6 that double mounts with another along the load bearing side. You cool with that now?

Next we need to mark the area where the deck will be. This is called dropping plumb line. Plumb line helps to make the deck at 90 angles at the corners so that the final product does not become a parallelogram.

The deck is 12 feet by 22 feet, remember? It is 12 feet out and 22 feet wide and runs along the house. Take a 2X2 stake and hammer it in to the ground at one corner of the house. Align it so when you tie a string it will be at the corner. Next go 14 feet out and drive a stake into the ground. Now do the same at the other side. Next, we need to do a line along the 22 feet side right? So on both sides of 14 feet line measure 12 feet then go to spot approximately 24 feet (i.e. 2 feet beyond) and put a stake down. See figure 1.

Do the same at the other end. Tie the strings corner to corner at the level of your slab or the floor of the house less 1 ¾ inches. Use a string level to get the string to be at flat level to the other stake. Do the same with the other sides. Now measure the diagonals. See figure 1. They must be the same, if not move your corner stakes so that they are. Double check your work. Make sure the strings are at the floor level of your house less 1 ¾ inches. This is below the floor level because when you add the decking planks (1 inch) and the floor boards ¾ inch ply) you will be at the floor level right?

Now the strings represent the outer portion of your new foundation or your deck. Are you ready for some labor work? Use a post-hole digger and dig a post hole at the outer corner. The depth will depend on how soft the ground is. Dig until you hit hard surface usually one to two feet deep. If your ground is soft you may need to go deeper. In any case the bottom of your hole should be wider so the hole looks like the elephant's foot and wide enough to hold 4X4 with at least two inches around for concrete. This is going to be your first column. How long should the 4X4 be? Well it should be from the string to the ground plus the depth of the hole less 6 inches. Keep reading, it will be clear in a moment.

Since the beam will be attached to the column you will need to space this. Easiest way to do this is to cut four six inch length of a 2x4. Attach with ‘screws' to the beam as shown in figure 2.

Mix concrete pour about six inch deep in the post hole. Set the post so that it rises to the string height. The 2x4 should be perfectly square to the two sides of the string as shown in figure 2. Then fill the rest of the hole with the concrete and come about two to three inches above the ground level so as to form a mound around the beam and about four to six inch diameter sloping down toward the outer edge so as to facilitate rain water run off. So now let me repeat. How long should the 4X4 be? Well it should be from the string to the ground plus the depth of the hole less 6 inches. Are you with me?

Repeat this process for all corners spacing it as shown in figure two. Let it all dry 24 hours so as to set completely. Mean while dig post holes every 4 feet for support posts and set them. For post holes you can dig straight down you do not need to do the elephant foot. Do not do the inside posts yet.

Day two: Unscrew the 2x4 spacers. Hang the 6x2 beams and secure it with six inch bolts. Be sure to stagger the bolts as the corner columns will take four, two on either side. For beams that will hang on the insides use double 2x6 metal hangers. Caution: Along the length where you will hang the beams stagger the joints so that the joints of each beam falls at least a few feet apart.

You are now ready to hang the rafters and secure them with posts.You can do this either way. From the end mark 16 inch center along the longer length of the deck on either side. Then install metal hangers. You will hang the rafters into these but do not nail them in as yet. Now every 4 feet along the rafter dig post holes. For post holes you can dig straight down you do not need to do the elephant foot. Then attach the posts to the rafters and then pour in the cement concrete using a rebar or a stick to remove any air bubbles from the concrete.

You can use 2x2 along the bottom edge of the beams and cut a notch in the rafters to hang them. This will be a little more cost effective but labor intensive. However it is easier to set the rafters at 16 inch centers. Be sure to use liquid nails. Once all your rafters and their posts are set, you are ready for the decking planks .

Day Three: Today all the concrete should be set. Install the decking planks. Use the 2 ½ inch spiral nails. Do not use liquid nails.

Lastly, saw off the deck edges for a neater appearance. Remember the deck will be ¾ inch below the floor level. When you decide to build rooms on top of the deck start with laying down the ¾ inch floor first and then put the framing on top of it. Good luck.

Materials List:

All wood is pressure treated.

For beams and rafters 2x6. These are available in 8 fet, 10 feet, 12 feet 14 feet and 16feet lengths.

For columns and posts 4x4 available in 8, 12 and 16 feet

2x2 for hanging rafters or you can use 6 inch 2x6 metal hangers.

2x6 double metal hangers

2x6 single hangers you can sub this with 2x2

Spiral Decking nails 3 ½ inches for rafters and 2 ½ inches for the decking planks

Heavy duty liquid nail. Use on all wood joints.

6 inch wood bolts

Decking planks 1X 6 if you use 5/8 planks be sure to adjust the floor height accordingly.

Concrete mix