How to Lay Out the Foundation for a Deck

After the ledger board and joist hangers are installed you can begin to lay the footing for the posts.

Difficulty: Easy

Instructions

Things You'll Need:

• Strong String
• Toy Hammers
• Long Tape Measure

1. Use string to lay out the shape of deck.

2. Drive stakes or batterboards into the ground about 12' to 18' beyond the approximate locations of the corner posts. (WHAT DO YOU MEAN ON ADJACENT SIDES?). Stakes should be the height of the ledger board.

3. Find the exact location for the center of the post by measuring out from wall of the house. Hammer a nail into the ledger board in line with the center of the corner post. (IS THE EXACT LOCATION OF THE CORNER POST KNOWN?) at the left side of the deck.

4. Tie a string to the nail, then stretch it to the batter board at the opposite corner of the layout.

5. Square string using the 3-4-5 method (see Tips below), then attach to the stake. This will make sure that the layout is square and that all of your measurements are equal and true. WHAT ARE YOU ACCOMPLISHING HERE?

6. Repeat above steps for the right side.

7. Mark the location of the corner post on each string, checking that the string is level.

8. Stretch a string parallel to the house and between these two corner points to mark the outer edge of the deck. Check for level and fasten to stakes. (AREN'T THE STAKES FARTHER OUT THAN THE ACTUAL EDGE OF THE DECK WILL BE?)

9. Measure diagonals and adjust strings until diagonals are even.

10. Line up plumb bob where strings cross.

11. Drop bob to ground level and mark on ground with colored string on a nail. This will be the center of the hole for that corner post.

12. Repeat for other side.

13. Measure along outer string line to mark locations of other posts (be sure tape measure is level).

14. Mark other post locations with plumb bob and colored string.

Tips & Warnings

• To use the 3-4-5 method, measure from the mark on the ledger board and mark the string at 3 feet. From the same mark measure along ledger board and mark at 4 feet. The diagonal of the 3-foot mark and the 4-foot mark should be 5 feet. If not, move string left or right to adjust as needed. You can use this method with any multiple of 3-4-5. For best results, use the largest multiple you can.
• Now that the footing is layed out you can dig holes and prepare to place post.