How to Build a Bilevel Raised Deck

Follow your architect's or engineer’s plans, which may require approval by your municipal permits department to ensure code compliance, to attach a ledger to the wooden framing above your foundation wall. Set concrete footings as dictated by the plans, typically two rows of three footings topped by 4-by-4 posts. Set the posts in post anchors to support the rim joist, at the opposite end of the deck from the ledger, and the beam, typically a doubled piece of 2-by-10 lumber, about halfway between the ledger and rim joist.

Lay a 2-by-4 from the ledger to each support post designated to support the beam. Lay a spirit level on top of the 2-by-4 so you mark a point on the post horizontal with the ledger. Make another mark lower on the post designating the depth of a nominal 2-by-6 joist -- typically 5 1/2 inches -- and another mark still lower designating the depth of the beam -- for a nominal 2-by-10, it will be 9 1/4 inches. Cut off each post with a reciprocating saw at the lowest mark -- in this example, 14 3/4 inches below the mark indicating a point level with the ledger.

Screw post-beam caps with galvanized deck screws on the top of each freshly cut post. With the help of an assistant, set the beam in the caps and screw through the holes in the caps to hold it in place.

Mark the joist positions on the ledger and the top of the beam with a carpenter’s pencil, with one mark at each end and additional joists typically 16 inches on center, unless your architect decrees otherwise given special materials or designs. Transfer the joist marks on top of the beam to the face of the beam with a carpenter’s square. Nail or screw joist hangers into the ledger.

Cut joists with a chop saw to run from the ledger to the face of the beam, less 1 1/2 inches to allow space to attach a band joist. Attach the ledger end of the joists by nailing galvanized nails through the holes in the joist hangers. Toenail the beam end of the joists into the top of the beam. This creates framing for the upper level.

Lay a 2-by-4 from the top of the beam to each of the posts that will support the rim joist. Mark a point on the posts horizontal to the beam top using a spirit level as in Step 2. Mark a lower point signifying the depth of your rim joist, typically a 2-by-10. Cut off the posts at this lower mark with a reciprocating saw.

Attach post-beam caps to the top of this far row of posts by screwing them in place. Lift the rim joist into position and screw the joist to the caps. Mark the locations for joist hangers on the inside of the rim joist and nail them in place. Cut and nail in place the joists to create framing for the lower level, running from the beam to the rim joist. Complete the deck following standard installation procedures for deck boards, posts, railings and balusters.