Squaring Up A Deck Frame

One way this old house general contractor tom silva ensures that mason s strings and deck framing are square when he is building a deck is by employing the 3 4 5 rule based on the pythagorean theorem.

Squaring up a deck frame.

A common mistake with diy ers is to forget to square the frame up or box. This is a crucial step that must be taken when building a house or when framing a simple deck. If the measurements match your frame is square. The single most important framing member is the ledger board.

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. Some guys gals prefer to use the 3 4 5 method or the cross over method i use both. It s a good idea to mark joist locations on the ledger and on the front facing rim joist before installation when you can lay the framing members side by side on a pair of sawhorses. Anyone wants to learn the way to square a deck should know the 3 4 5 method as many builders often use it to make sure they are building a square deck.

First he tacks a double joist hanger to one end of the ledger and slips a side rim joist into place. Slight tolerances can be adjusted before the joists are installed to prevent exaggeration. Using a square and a 4 level will also help verify that your deck form is level. 3 4 5 rule to ensure square layouts.

Measure again before and after your first deck board is installed and every few boards as well to ensure it stays square while building. Compare the opposite lengths of the perimeter of squares and rectangle forms these lengths should be the same. Obviously the more square the frame the better. As with all structures a long lasting durable and solid deck depends on a proper foundation.

Speed squares and framing squares are helpful tools for using in construction builders often use them to check the layout. If they don t push the two corners that are further away the long measurement back together a little and remeasure. A sagging collapsing or crooked deck is not only unsightly but also potentially dangerous.