Installing a new deck or replacing old, worn boards brings up an important question: what is the optimal thickness for deck boards? The right thickness impacts the deck’s strength, longevity, and cost.
Whether building a deck yourself or working with contractors, understanding deck board thickness will ensure you pick the best materials.
What is the Standard Thickness for Deck Boards?
For traditional wood decking , boards are commonly 1 inch thick. This provides adequate strength when installed on joists spaced 16 inches apart. At 1 inch thickness, wood boards like cedar and pressure treated pine have sufficient stiffness to handle typical foot traffic without excessive bouncing or sagging over time.
Standard 1 inch wood boards have been used on decks for decades and deliver reliable performance in most single family residential applications.
Overview of Typical 1 Inch Thickness for Wood Boards
- Commonly used thickness for decades
- Adequate strength and support at 16″ joist spacing
- Sufficient stiffness for typical residential foot traffic
- Works for most single family deck projects
While 1 inch offers time tested durability, depending on factors like decking material, spacing, and intended use, a thicker wood board may be recommended.
When Are Thicker Wood Deck Boards Needed?
For woods like cedar and redwood, thicker boards exceeding 1 inch may be required. These woods are naturally lower density and weaker than woods like Southern yellow pine. A thicker profile provides extra reinforcement to prevent excess sagging under live loads.
Situations Where Thinner Woods Require More Thickness
| Wood Type | Cedar, Redwood |
| Purpose | Prevent sagging when weaker wood used |
| Thickness | Over 1 inch |
Additionally, choosing boards thicker than the minimum 1 inch standard allows installing deck joists at wider spacing increments. This may reduce material requirements and overall cost. For example, a 2×8 cedar board at 1-1/4 inches thick could safely span joists at 24 inches apart.
Reasons for Choosing Thicker Wood Boards
- Allow wider joist spacing
- Reduce framing materials
- Lower project cost
- Add support for heavier structural loads
Check with your local building code for minimum thickness rules. Many areas require at least a 1 inch thick profile regardless of species used.
How Thick Are Composite Deck Boards?
Wood-plastic composite decking offers exceptional durability and usually maintains its stiffness even at a 1 inch thickness. Brands like TimberTech use advanced manufacturing processes to encapsulate wood particles or fibers within a resilient plastic shell.
The result is a stiff, engineered product capable of spanning up to 24 inches between joists while resisting moisture damage.
Composite Strengths with 1 Inch Boards
| Material | Composites like TimberTech |
| Durability | Resists moisture, lasts decades |
| Span Rating | 24″ between joists typical |
Quality composites achieve this strength consistently at 1 inch thickness due to advanced formulations and molding processes. So when comparing wood and composite lifespan, pound for pound composites maintain their stiffness longer before requiring replacement.
How Does Board Thickness Impact Deck Cost?
Thicker deck boards allow installing joists at wider intervals because each board reliably spans further between supports. With fewer total joists needed, material requirements and construction labor costs decrease.
For example, a 1 inch cedar deck board may only span 16 inches safely. But at 1-1/4 inches thick, the allowable span increases to a full 24 inches. That 25% increase in thickness enables 33% fewer joists over an equivalent surface area.
Since treated lumber and composite prices are comparable per linear foot, using thicker boards to space joists further apart directly reduces expenditures. But relatively cheap woods like cedar and redwood may warrant using thinner boards to control project budgets.
Thicker Boards Allowing Wider Joist Spacing
- Decreases framing lumber requirements
- Lowers material costs
- Reduces construction labor time
- Enables budget friendly deck projects
Homeowners must balance cost savings from thinner pieces against longevity gains with thicker counterparts that may add more long term value.
Do Intended Uses Change Thickness Needs?
Decking thickness should align with intended uses above and beyond typical foot traffic and family gatherings. Structural enhancements like planter boxes, hot tubs and storage compartments demand thicker, stiffer boards.
For wood decks, thicker profiles handle excess moisture better if staining regularly. Alternately, thinner bare wood boards avoid cupping and warping when left unstained in arid climates. Always choose materials suiting local conditions and maintenance preferences.
Accommodating Heavy Structural Additions
- Planter boxes
- Hot tubs
- Storage compartments
Barefoot Traffic vs. Staining Requirements
- Thicker wood holds up better when stained
- Thinner wood avoids cupping if unstained
Review potential additions and finishing plans before purchasing boards. Consulting a deck builder or architect ensures adequate thickness and spans for custom structural features or heavy items.
Climate Impact on Best Thickness
Regional climate influences material selection for optimal deck board thickness:
- In wet climates, thicker boards resist absorbing excess moisture
- In arid climates, thinner boards are less prone to cracking or checking
Hot and cold cycles, along with precipitation rates, determine appropriate decking thicknesses. Freeze-thaw fretting corrodes thinner wood faster through accumulated moisture exposure over years of use.
Homeowners must comply with local building codes mandating a minimum thickness to satisfy snow load design requirements.
Seeking location-specific guidance ensures installing decking thick enough to withstand prevailing conditions and continue providing years of practical use with normal care and maintenance.
Effect of Thickness on Lifespan
Specifying thicker deck boards boosts the functional lifespan before requiring replacement. The additional thickness leaves more material to slowly erode from exposure before decking becomes unsafe or unsightly.
However, thicker pieces shrink and swell marginally less across changing moisture content as wood dries out or absorbs water. This slightly improves long term stability and splinter resistance.
Meanwhile, thinner pieces are cheaper and easier to replace more frequently over ownership periods spanning decades.
Relationship Between Durability and Replacement
- Thicker = Longer lasting before replacement
- Thinner = Cheaper and easier to replace periodically
Homeowners must decide between two replacement philosophies: 1) Thicker for longer intervals between maintenance. 2) Cheaper and easier replacement at higher frequency.
Gaining expertise consulting regional deck builders provides valuable perspectives on ideal thickness for maximizing value over years of enjoyment.
Influence on Aesthetics and Accessibility
Thicker deck boards lend a more substantial, premium aesthetic compared to thinner counterparts. Visually, thicker boards make a deck appear higher-end and professionally crafted.
Accessibility ties closely with board thickness selection. For universal design accommodating wheeled walkers and mobility devices, thinner boards with tighter seams or spacing create a smooth, flat path without large gaps or lips.
However, thicker boards feel more stable underfoot, reducing wobbliness for those needing steadier footing navigating steps between levels.
Visual Thickness Enhancing Appearance
- Higher-end, quality visual appeal
Mobility Considerations for Accessibility
- Thinner boards accommodate wheelchairs and walkers navigating tight seams and transitions
- Thicker boards offer more stability and support underfoot
Balancing accessibility accommodations and aesthetic impacts allows tailoring decking thickness to homeowner priorities when planning projects.
Other Factors to Consider
Secondary impacts tied to thickness selection help finalize decisions balancing cost, durability and performance trade-offs over the intended lifespan:
- Sound Absorption : Thicker boards dampen echoed noise from footsteps and conversations
- Fire Safety : Added thickness slows ignition in regions at risk of wildfires
- Energy Efficiency : Thicker wood insulates marginally better year-round
Thinking through special environmental needs and noise preferences aids choosing well-suited decking materials at the appropriate thickness.
Home improvement stores provide general guidelines on deck board sizing aligned with common residential needs. But tapping local deck builders’ and manufacturers’ expertise tailors board thickness Selection optimally based on:
- Climate conditions
- Code requirements
- Cost targets
- Material attributes
- Performance needs
Homeowners can choose the right thickness of deck for their project with experience.