A Deck Blog

Laying out the deck

The first thing I did to begin the layout is mark the house's foundation where the top of the posts will be such that the deck will end up being even with the threshold of the door. I then used a water level and calibrated it to be level with the mark on the house.

The water level turned out to be REALLY REALLY accurate and useful and I would highly recommend to anyone when building a deck. I put it together for about $2. All I needed was 20 feet of 3/8" inside diameter tubing, a gallon milk jug and some blue food coloring.

Once the foundation was marked I began adding my batter boards. The water level was used to determine the height of the horizontal pieces of the batter boards so they were all level with each other.

Layout after 4 pairs of batter boards added and string setup

First I added the strings for sides of the deck that will be parallel to the house. There is a screw in each of the batterboards that are right up against the house. These screws are exactly 24 feet apart. The far string that is parallel to the house is about 30 feet long and exactly the same distance from the house on both ends. Then I used 2 tape measures and used the "perpendicular bisector method" to determine where to place the strings that will outline the sides of the deck that would be perpendicular to the house. Once all the corners were outlined I tested for square by measuring corner to corner and the layout was confirmed to be perfectly square.

Perpendicular Bisector Method

One tape measure was hooked to a screw on one of the batter boards against the house. The second tape measure was hooked to a screw on the other batter board against the house. The two tape measures were pulled out and crossed over the far string parallel to the house. The point where the measurements are equal on both tape measures when they cross the string is the exact center of the side of the deck parallel to the house. From this point I measured 12 feet in each direction (For 24 foot deck) and marked the string for the corners of the deck. The strings running perpendicular to the house will cross these marks on the string. These crossings will indicate the corners of the deck furthest from the house.

Layout Complete

I added a few more batterboards and strings parallel to the house that marked the post lines. I also hammered in some stakes where the holes for the posts were to be dug. This made the digging go quickly and smoothly. Ths posts were both about 42" from the end of the deck on both sides (deck uses a 42" joist cantilever on each end) and about 4 feet apart. There are 14 posts in total.

Next Section - Digging