How To Lay Decking Joists For A Strong Deck Frame

Installing a deck expands your home’s livable space into the outdoors. With proper planning and construction, a deck framed with the right joist sizes and spacing becomes a lasting backyard asset. This guide covers key steps for designing and building a sturdy, code-compliant deck frame.

Deck Builder

Planning Your Deck Joist Layout

Careful planning is crucial when framing a deck. Consider the following factors when designing your joist layout:

Intended Deck Size

First figure out the overall deck size and layout that best fits your available outdoor space. Standard decking boards come in widths of 2, 5 or 6 inches. To properly span across the joists below, choose deck boards no wider than your joist spacing.

The decking material weight and thickness determines the maximum joist spacing. For 5/4 thick wood deck boards, space joists every 16 inches on center. Thinner composites require joists every 12 inches. Heavier materials like natural stone need tighter joist spacing.

Joist Span Lengths

The allowable joist span distances vary based on the joist dimensions and wood type/grade. For example, a 2×8 No. 2 grade SYP joist can span 7′-11″ on center when spaced 16” apart. Use the deck framing tables to select the proper joist size for your required span lengths.

Joist Direction

Run joists perpendicular to the house for straight structural spans. Positioning the ledger parallel with the joists provides solid attachment. Joists running parallel to the home require extra framing work.

Ledger Board Attachment

Use lag screws or bolts to securely attach the ledger to the house. Consult codes for proper sizing, spacing and installation method based on the house’s construction. Flashing above the ledger prevents water intrusion issues.

Thoroughly planning your deck’s framing ensures it gets built right the first time to handle the intended structural loads. Now let’s look at the process of actually installing the deck joists and frame.

Deck Joist Layout

Building The Deck Frame

Constructing a code-compliant deck frame requires completing these steps in the proper order:

Install The Ledger Board

Start by attaching a treated ledger board to the house at the correct height and location. Use corrosion-resistant lag screws or bolts to fasten it securely per code requirements. Apply flashing above the ledger to direct water away.

Set The Deck Posts

Determine post sizing and exact locations from the framing plan. Dig holes for concrete pier footings per code. Insert steel post anchors and J-bolts into the concrete. Allow footings to cure before inserting posts.

Install Beam(s)

Measure and cut beam boards to required lengths. Set beams across pairs of posts and verify level. Fasten beam boards together with galvanized hardware. Use double or triple beam assemblies for longer spans.

Attach Joist Hangers

Use galvanized joist hangers sized for the joists to connect them to the ledger and beams. Follow the hanger manufacturer’s specifications for correct fastener type, size and spacing.

Cut Joist Boards

Measure between the ledger and beam. Cut 2x deck joists to required lengths with square ends. Meet minimum joist size requirements from the framing tables based on the span.

Install Joists

Working from one end, set joists into hangers at proper **joist spacing** per plans. Check each joist is level end-to-end before fastening completely into hangers.

Add Blocking

Cut and install blocking securely between joists at all supports and intervals of 4-6 feet. Blocking stiffens the overall frame. Use full-depth 2x lumber.

Install Rim Joists

Cut rim joists to length and fasten them to beam and ledger board ends. Rim joists tie all joists together providing critical structural stability.

 

Once all joists are installed with proper blocking and rim joists, the structural framing is complete. Verify all connections are secure and properly fastened before moving on.

Deck Frame

 

Best Practices For Deck Framing

Following codes and using smart building techniques ensures a stable, long-lasting deck frame. Keep these tips in mind:

  • Check span tables to select the right **joist size** to prevent sagging
  • Maintain proper **joist spacing** for decking weight and thickness
  • Stagger joist butt joint locations to avoid weak points
  • Use galvanized hardware throughout for corrosion resistance
  • Build double or triple beam assemblies for rigidity on longer spans
  • Install blocking and diagonal bracing for a stronger frame
  • Attach ledger to house with lag screws, not nails, for durability
  • Verify joists are level across the entire span
  • Ensure joist hangers fit correctly and use manufacturer’s specified fasteners
  • Use built-up beams from multiple plies for greater load capacities

Building your deck right the first time prevents the need for costly repairs down the road. Follow codes, use decay-resistant lumber, and incorporate smart structural techniques.

 

Deck Framing Code Requirements

Deck construction must adhere to building code regulations. Here are key International Residential Code requirements:

Ledger Attachment
  • Use 1/2″ diameter lag screws or bolts
  • Embed bolts minimum 2” into rim joist or band board
  • Space lag screws per IRC Table R507.2.1.1
  • Anchor vertically to minimum 4×6 posts
Deck Post Sizing
  • 4×4 posts up to 8′ height
  • 6×6 posts up to 14′ height
  • Notch posts maximum 6” if over 6′ tall
Footing Sizes
  • 12” minimum diameter for round footings
  • 6” minimum diameter for pier footings
  • Extend all footings 12” below grade minimum
Joist Size And Allowable Spans
  • Size joists using IRC Table R507.5 span requirements
  • Space 2×6 joists maximum 16” on center
  • Space 2×8 or larger joists maximum 24” on center

Following these code guidelines ensures your DIY deck frame meets regulatory standards.

 

Typical Deck Framing Lumber

Use weather-resistant lumber approved for structural deck construction. Common choices include:

Pressure-Treated Lumber
  • Inexpensive and readily available
  • Treated for rot and insect resistance
  • Creates strong, durable frames
  • Prone to splitting, cupping, twisting
Naturally Durable Wood
  • Decay-resistant cedar, redwood, cypress
  • No chemical treatments needed
  • Costs more than pressure-treated
Redwood
  • Beautiful reddish-pink color
  • Naturally repels insects and rot
  • Durable but very expensive
Composite Lumber
  • Wood/plastic mix resists moisture
  • Dimensionally stable, no splitting
  • Easy to work like wood
  • Costs more than real lumber

Use lumber suited for your climate to build a durable frame that withstands the elements. Verify substitutions meet code requirements.

Deck Framing Lumber

 

Deck Framing Lumber Dimensions

Framing lumber uses standard nominal sizes:

  • 1-1/2″ x 3-1/2″ – Nominal 2×4
  • 1-1/2″ x 5-1/2″ – Nominal 2×6
  • 1-1/2″ x 7-1/4″ – Nominal 2×8
  • 3-1/2″ x 3-1/2″ – Nominal 4×4
  • 5-1/2″ x 5-1/2″ – Nominal 6×6

The actual dimensions are smaller than the nominal size due to drying shrinkage after milling. Using the listed actual dimensions ensures proper fit when assembling the deck frame.

 

Tools For Framing Decks

These basic tools are useful when framing a deck:

  • Circular or miter saw – Cut boards and posts squarely
  • Drill/driver – Drive screws, lags, and bolts
  • Level – Check beams, posts and joists are level
  • Tape measure – Verify measurements and spacing
  • Hammer – Tap joists into hangers and set anchors
  • Shovel – Dig proper holes for footings
  • Wrench – Tighten bolts attaching ledger
  • Safety gear – Gloves, glasses, dust mask

Invest in quality tools for easier, faster, and safer deck construction. Sharpen saw blades and pre-drill dense lumber to prevent cracking and splitting.

 

Using Deck Framing Plans

Build your deck using a detailed plan with measurements for the entire frame. Essential drawings include:

Site Plan – Deck location, size and layout on the property

Footing Plan – Footing sizes, post spacing, pier locations

Framing Plan – Beam spans, joist direction and spacing, blocking

Attachment Details – Lag screw spacing, flashing, footings, connections

Having all framing details mapped out in a plan streamlines the building process and prevents mistakes.

 

Installing Deck Boards

Once the underlying frame is complete, you’re ready to install deck boards across the joists. Follow these tips:

  • Allow 1/4″ spacing between boards for drainage
  • Stagger end joints between rows
  • Use two screws per board at each joist
  • Keep fasteners 2″ from board edges
  • Use hidden fastener systems for smooth surface

Properly installing decking completes your new outdoor living area! Enjoy for many years to come.

With careful planning and persistence, you can tackle building your own deck framing. Follow codes and sound structural principles. Use decay-resistant treated lumber and corrosion-proof hardware. Refer to detailed plans and framing diagrams. The result will be a long-lasting, safe deck frame ready for decades of use.

 

Installing Deck Boards

 

Planning Stairs On Decks

Decks often require stairs for safe access. Consider these points when planning deck stairs:

  • Entryway location – Place stairs in the most convenient access point.
  • Number of stair units – Determine width needed to accommodate traffic.
  • Stair unit width – Standard widths are 36” or 48”.
  • Total rise – Calculate overall height from deck to ground.
  • Maximum riser height – Code limits individual riser height, typically to 7”.
  • Number of risers – Rise divided by riser height gives number of steps.
  • Tread depth – 10” minimum tread depth per code.
  • Stair framing – Cut stringers to proper rise and run.

Smart planning of stairs prevents issues and ensures safe access for years to come.

Framing Stair Stringers

Stringers support the stair treads and transfer loads properly. To frame stringers:

  • Mark rise and run on 2×12 boards
  • Cut notches for each riser and tread
  • Attach stringers to deck rim joist
  • Install treads into notched stringers

Properly notched and installed stringers provide the structural stability for safe deck stairs.

Stair Railings

Railings are crucial for safety on exterior deck stairs. Follow code requirements:

  • Install graspable handrails 34-38” above treads
  • Post balusters spaced no more than 4” apart
  • Use pressure-treated wood or rot-resistant railings
  • Anchor railings securely to resist loads

Proper stair railings prevent falls and injuries when accessing decks.

Options For Deck Stairs

Beyond basic wood stairs, consider these stair options:

Pre-Fab Stairs

  • No cutting or assembly
  • Available in wood, metal and composite
  • Adjustable heights and widths
  • Cost more than building from scratch

Spiral Stairs

  • Compact, space-saving design
  • Creates unique aesthetic
  • Requires special fabrication
  • Difficult DIY installation

Curved Stairs

  • Flowing, elegant appearance
  • Easier DIY than spiral stairs
  • Use flexible stringers or custom framing
  • Needs large landing for curves

The right stair solution depends on space constraints, access needs and style preferences.

Options For Deck Stairs

 

Permits For Deck Construction

Most areas require permits for deck construction. The permit process ensures:

  • Code compliance for safety
  • Awareness of easements or restrictions
  • Professional plan review
  • Opportunity for inspections

Check with your local building department about permit needs, costs, required plans, and inspection procedures. Factor the permitting process into your project timeline.

 

Hiring A Deck Builder

Deck construction is complex. Hiring a professional provides these benefits:

  • Handles all permit processes
  • Creates an engineered design
  • Professionally constructs every component
  • Has special equipment to facilitate installation
  • Provides certified construction and materials
  • Gives a warranty for workmanship

While DIY decks can save money, the quality and expertise of professional builders is invaluable for such a massive structural project.

 

Cost To Build A Deck

Deck construction costs depend on:

  • Deck size – Bigger decks cost more.
  • Materials – Hardwoods, composites or natural stone cost more than pressure-treated pine.
  • Accessories – Railings, benches, lighting, pergolas add expenses.
  • Foundation – Elevated decks require extensive footings and framing.
  • Labor – Hiring a contractor is more expensive than DIY.

On average expect to pay $15-50 per square foot for wood deck construction. $50-100 per square foot for upscale composite or alternate materials.

 

Protecting Your Deck

Make your investment last by protecting and maintaining the deck:

  • Seal or stain regularly to protect wood from sun and rain
  • Keep decking clean and dry to prevent slip hazards
  • Inspect annually for loose fasteners, damage, or decay
  • Re-stain railings and replace deteriorated deck boards as needed
  • Consider waterproofing sealers and composite decking for easier maintenance

With proper care, your deck can last 20-30 years or more!

 

Building a deck greatly expands your home’s livable space and provides years of enjoyment. Now you’re ready to tackle planning and constructing a safe, code-compliant deck frame and stairs with confidence. Pay close attention to structural details as you lay the framing components. Soon you’ll be relaxing in your new outdoor living oasis!

Learn more: How To Build Deck Footings?

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