# Formula For Squaring A Deck

**Cut your perimeter boards at 45 degrees angles to butt together at the corners and screw into place.**

**Formula for squaring a deck**.
The best place to start is in one corner of the layout.
For squaring up a deck foundation or anything else that needs to be square use the 3 4 5 rule.
Here are all about how to square a deck using the 3 4 5 method.

The end of the left leg is a the corner is b and the end of the right leg is c. This will only work if the form you are testing has symmetrical geometry. B is the corner.

In the case of a square or a rectangle you will measure diagonally from corner to corner on both sides. Add them together and you get 25 which is also 5 x 5. Fix your deck to its supports with brackets braces or stakes and recheck that its slightly off level to the side.

Use the 6 8 10 or 3 4 5 rule to determine square or right angles in deck porch floor wall or roof framing or any other building framing or construction task to check a single corner for square use the 6 8 10 rule or if the sides are too short use 3 4 5 technique. The corner should be a right angle with two legs. 3 x 3 9 4 x 4 16.

There are also lots of different types of carpenters squares available to check for square on a smaller scale and for marking square lines when setting out. Adjustments usually mean moving the one side either the 3 foot or 4 foot triangle leg in or out to obtain the square 5 foot measurement. Once the perimeter boards are in place you can square the deck using two tape measures.

That is to say 3 squared plus 4 squared 5 squared. Tie a string between a and b to create left leg a and tie a string between b and c to create right leg c.