Multilevel Cascade Deck Railings
This seemingly complex deck provides an ideal solution for a steeply-sloping site. Its platforms cascade downhill, providing an outdoor connection between the upper and lower floors of the house. Built in a series of independent platforms, connected by stairways and steps, this design avoids a problem common to many high decks: it doesn’t overshadow and darken the rooms on the lower floor. Downstairs windows of this home still have sunlight and views.
The deck system consists of four platforms, two stairways of equal length, and a step between the two lower levels. Two of the platforms are attached to the house with ledgers and two are freestanding. The freestanding platforms and the outer edges of the attached levels are supported by posts set on concrete piers that extend below the frost line.
Organize your work
Building this deck may seem like a formidable task, but it will proceed smoothly if you organize your work in sections. Start with the platforms connected to the house first, then proceed to the intermediate platforms.
Layout and footings
- Set batter boards, and stretch a length of mason’s line parallel to the side of the house along the center of the three main posts.
- Dig the holes for the footings and piers.
- Set the forms, and pour the concrete.
- Insert metal post anchors in the wet concrete, making sure they are in line with one another and facing the right direction.
- Repeat the process for the lowest platform.
- Bolt the 2×8 ledgers to the house, 2/2 inches below the floor levels. Note that the ledger for the lower deck has a 2×8 stringer connected to it near the corner of the house.
Bolt the posts to the piers, then plumb and brace them temporarily. Do not cut them to exact length until you’ve built the deck platform.
Stringers and joists
Position the top of the 2×8 stringers 5/2 inches below the top of the ledgers, and fasten them to the posts with two %’inch bolts at each post. In most cases, the stringers will extend 1 inches beyond the posts to carry the outermost joists.
- Hang double 2x8s at the top of each stairway.
- Attach the joists to the ledger and rim joist with joist hangers, using 45-degree hangers at 45-degree intersections.
- Install blocking at the midpoint of any joists longer than 10 feet.
On the small platform between the two stairways, the joists are 16 inches on center, so you can install the decking diagonally to accentuate the deck’s direction of flow.
- Screw the 2×6 decking perpendicular to the joists on the three main platforms.
- Allow the ends of the decking boards to overhang the band joists 3 or 4 inches.
Each stairway is supported by three 2×12 stringers. The actual dimensions of the stringers will vary depending on the requirements of each site. And, although the exact width of the treads will depend on the run of your stairway.
- Calculate the rise and run of your stairs.
- Attach the tops of the stringers to the double 2x8s with joist hangers.
- Fasten the bottoms to the decking boards with wood cleats.
- Nail the risers to the stringers, and then screw the treads in place.
The railings in this design are supported by extensions of the 4×4 posts.
- Measure and cut each post so the top of the cap rail will be 36 inches above the decking (or as local codes require).Attach the framing clips to the posts, then slide the stringers into them.
- Once the stringers are in place, toenail 2×2 balusters between them, spacing them as required by local codes (usually no more then 4 inches).
- After the balusters are in place, nail the 2×6 cap rail to the top of the posts.
- Cut a 2×4 block to fit between the decking and the bottom rail at its midpoint and nail it in place, this will prevent the rail sections from sagging over their 6-foot span.
- Cut another block to fit between the top rail and the cap rail.
- Finish the deck with preservative and stain or paint it to match the overall scheme of your landscape design.