The Deck Professor

Every number here is a working estimate to check with your building authority. Whoever prints this page takes responsibility for what is in it.

Lessons

100 lessons, 17 subjects, in build order.

Site and permits

Permits, engineers and site limits. 7 lessons.

  1. Which permit this deck needs. Change it. Move this deck around the lot and up and down, then apply for what it needs.
  2. When an engineer must stamp it. Guess first. Guess whether this deck needs an engineer, then try other sizes and heights.
  3. Measure height at the worst corner. Change it. Measure this deck the way the code measures height.
  4. Overhead wires above the deck. Change it. Find a deck height that leaves room to stand under the service wire.
  5. Locate buried lines before digging. Change it. Lay out the footings clear of what is buried.
  6. When the city wants drawings. Change it. Size this deck, then decide what goes in with the application.
  7. When a deck counts as lot coverage. Change it. Raise and lower the deck, and find where it starts counting against your lot.

Footings, frost and posts

What holds the deck up. 6 lessons.

  1. Footings below the frost line. Watch it happen. Play the winter, then set the footing where frost cannot reach it.
  2. Bear on undisturbed soil. Change it. Place the house side footing where it will not settle.
  3. Pier blocks need access to re-level. Change it. Set this low deck up so its pier blocks can be re-levelled.
  4. 4x4 or 6x6 post. Change it. Pick the post this beam and this height call for.
  5. Pier, pier block or screw pile. Side by side. Compare the three footings, then choose one the permit will accept.
  6. Set the post off the concrete. Change it. Stand this post so it lasts.

Ledger and attachment

Attaching safely to the house. 6 lessons.

  1. Ledger or freestanding. Change it. Decide how this deck meets this house.
  2. Bolting the ledger. Click the fault. Click what would let go at this ledger, then fasten it properly.
  3. Flashing over the ledger. Watch it happen. Make it rain, then keep the water out of the house.
  4. Metals that corrode each other. Guess first. Guess what happens where these metals meet, then try each flashing.
  5. How a ledger fails. Watch it happen. Move time forward, then build it so it holds.
  6. Tying the deck to the house floor. Change it. Pull on the deck, then tie it in so it cannot leave the wall.

Joists and spans

Size, spacing and span. 8 lessons.

  1. Deeper joists span farther. Change it. Pick a joist deep enough for this span.
  2. Closer joists buy span. Change it. Push the joists apart until the span table refuses.
  3. Incised lumber spans less. Side by side. Read the span for these joists from the right column.
  4. Species changes the span. Side by side. Read the span for this species from the right column.
  5. A 2x8 rim for guard posts. Click the fault. Click the part too shallow to hold a guard post, then change it.
  6. Where a joist cannot be cut. Click the fault. Click each cut that weakens this joist, then fix them.
  7. Hangers need their own fasteners. Click the fault. Click what is wrong in this hanger, then fix it.
  8. What blocking is for. Click the fault. Click the weak spot behind the guard posts, then fix it.

Beams, posts and cantilevers

Carrying the joists to the ground. 9 lessons.

  1. Span plus cantilever picks the beam. Guess first. Choose the span you would look this beam up with.
  2. Post spacing against beam size. Side by side. Compare the post spacings, then build one.
  3. Single span or two span beam. Change it. Read the middle beam from the table that matches its load.
  4. How far joists may overhang. Change it. Find the longest cantilever each joist allows.
  5. When a cantilever is better. Try options. Try cantilevers on your deck and find one that works on this lot.
  6. Beam overhang past the post. Change it. Trim the beam overhang to what this beam can carry.
  7. The beam sits on the post. Click the fault. Click how this beam is held up, then seat it properly.
  8. Building up a beam. Spot it. Move the joint in this beam to where it belongs.
  9. Drop beam or flush beam. Change it. Build the beam so the joists sit safely on it.

Decking and patterns

Boards, patterns and joist spacing. 7 lessons.

  1. Board thickness sets joist spacing. Change it. Match these boards to a joist spacing they can span.
  2. Diagonal boards pull joists closer. Change it. Lay these boards on the diagonal without letting them span too far.
  3. Blocking under a picture frame. Click the fault. Click what this border is missing, then add it.
  4. Composite follows its own report. Change it. Set the joist spacing these composite boards ask for.
  5. Gaps let the water through. Change it. Set the gap so water drains off the joist.
  6. Where board ends meet. Change it. Arrange the board ends so every joint is carried.
  7. Screws, clips and nails. Change it. Pick a fastener that stays put as the boards move.

Guards and railings

Height, openings and post strength. 9 lessons.

  1. When a guard is required. Change it. Raise and lower this deck, and give it the guard it needs.
  2. 900 mm (35 7/16 in) or 1.07 m (42 in). Guess first. Guess first, then set the guard height for this deck.
  3. What counts as the ground. Change it. Look past the deck edge, then decide whether it needs a guard.
  4. The 100 mm (3 15/16 in) sphere test. Click the fault. Test each opening with the 100 mm (3 15/16 in) sphere, the stair included. Find every one it passes..
  5. Gaps under rails and beside stairs. Change it. Close every gap a 100 mm (3 15/16 in) sphere could pass.
  6. Nothing to climb above 4.2 m (13 ft 9 5/16 in). Change it. Raise the deck, then choose an infill a child cannot climb.
  7. Guard posts carry the push. Change it. Lean on the guard, then fasten the post so it holds.
  8. Can a bench be the guard. Change it. Make this bench count as the guard.
  9. Glass, cable and aluminum guards. Change it. Put up this manufactured guard with what the permit needs behind it.

Stairs, landings and handrails

Rise, run, stringers and rails. 9 lessons.

  1. Rise and run limits. Change it. Change the risers and treads until this stair passes.
  2. The bottom riser trap. Change it. Mark out this stringer so every riser comes out the same.
  3. When a stair needs a landing. Change it. Fold this tall stair into flights, and make the landing safe.
  4. How wide a stair must be. Guess first. Guess first, then try other widths on this stair.
  5. Handrail or guard cap. Change it. Choose a top rail a hand can hold.
  6. Stringer depth and spacing. Guess first. Guess first, then try each stringer size.
  7. Where the stringer meets ground. Click the fault. Click the two weak ends of this stringer, then fix them.
  8. Tapered treads and spirals. Change it. Widen the narrow end of these tapered treads until they pass.
  9. Lighting the stair. Spot it. Light this stair so every step shows after dark.

Water and durability

Keeping the frame dry. 6 lessons.

  1. Room for air underneath. Change it. Give this frame room to dry.
  2. Venting the space underneath. Change it. Let air move under this deck.
  3. Tape on the joist tops. Spot it. Keep water out of the screw holes along this joist.
  4. Dry space under the deck. Spot it. Set up the drainage under this deck so it keeps working.
  5. Ground that slopes away. Spot it. Shape the ground so water leaves the house.
  6. What to check each spring. Put in order. Put the spring check in order.

Materials and fasteners

Treatment, species and metals. 5 lessons.

  1. The 6 in treatment zone. Change it. Find the wood that sits too close to the ground, then fix it.
  2. Treat every cut end. Change it. Put the treated end of this post where it counts.
  3. Cedar heartwood and sapwood. Spot it. Choose a post that will not rot at the ground.
  4. Fasteners that match the treatment. Spot it. Pick screws and hangers that survive treated wood.
  5. Which wood goes where. Spot it. Pick the lumber for the ledger.

Hot tubs and heavy loads

Where the span tables stop. 5 lessons.

  1. A hot tub on the deck. Change it. Put a hot tub on this deck and get it approved.
  2. Tub on the ground, deck around. Spot it. Frame the deck around the tub so it can still be serviced.
  3. Power and heat for a tub. Change it. Plan how power and heat reach the tub before the frame closes.
  4. A roof over the deck. Change it. Add a roof over this deck and get it approved.
  5. Barbecue islands and fireplaces. Change it. Set a masonry barbecue island on this deck and get it approved.

Lateral bracing

Stopping sway on tall decks. 3 lessons.

  1. Tall decks sway. Change it. Push the deck, then stop it swaying.
  2. Brace the corner posts. Change it. Push the deck both ways, then brace it so neither push moves it.
  3. Bracing a freestanding deck. Change it. Push this freestanding deck sideways, then brace it.

Ramps and door landings

Ramps, slopes and door steps. 4 lessons.

  1. Slope sets ramp length. Guess first. Guess how far the ramp reaches, then change the slope and watch it.
  2. Folding a ramp to fit the yard. Change it. Fit this ramp inside the yard.
  3. The step down from the door. Try options. Lower the deck below the door and see what the door needs.
  4. Ramps to an upper deck. Guess first. Guess how much ramp a deck 9 ft up needs, then try it.

Shapes and levels

Low, wraparound, two level, upper. 4 lessons.

  1. A guard on a low deck. Change it. Space the pickets on this low deck so no child gets caught.
  2. Wrapping around a corner. Change it. Price the guard for this wraparound deck.
  3. Two levels, one deck. Change it. Set the drop between the levels, and guard it if it needs one.
  4. A second storey deck. Change it. Pick the posts and the guard height for a second storey deck.

Layout, quantities and sequence

Squaring, quantities and build order. 4 lessons.

  1. Squaring the frame. Change it. Square the frame with 3, 4 and 5.
  2. Quantities from the shape. Change it. Order the deck boards for this deck.
  3. Waste by board pattern. Change it. Set the waste allowance for this board pattern.
  4. Build order and inspections. Put in order. Put the build in order, inspections included.

Inspection and common failures

Defects to look for. 5 lessons.

  1. Find five defects. Click the fault. Five defects hide on this deck. Click each one..
  2. The final inspection checklist. Change it. Get this deck ready for its final inspection.
  3. Inspect from the ground up. Put in order. Inspect this deck from the ground up.
  4. Rust where metal meets treatment. Click the fault. Click what the rust is telling you, then fix it.
  5. How old is this deck. Change it. Age this deck, add a tub, and decide when it needs a professional look.

Lighting and outlets

Lights, outlets and circuits. 3 lessons.

  1. Outlets on the deck. Spot it. Get power to the far corner of this deck.
  2. Lighting every change of level. Spot it. Light the stair without leaving any step in shadow.
  3. Plan the hot tub circuit. Put in order. Order the work so the tub circuit has a route.