5/4x6 Massaranduba Tongue & Groove Decking board profile diagram
Decking

5/4x6 Massaranduba Tongue & Groove Decking

This 5/4x6 Massaranduba Tongue & Groove decking board pairs the proven outdoor performance of Massaranduba (Brazilian Redwood) with a 3,190 Janka hardness rating — one of the hardest commercially available woods on earth. The interlocking tongue and groove profile creates tight, seamless joints for exterior decks, patios, and pool surrounds, with no visible fasteners on the finished surface. In stock and ships nationwide — order Massaranduba decking online or call 1-844-674-4455 for expert guidance.

5/4 x 6(1"×5.5" actual)[25.4mm × 139.7mm]
Contractor Trusted
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Ships Nationwide
SKU: MASS-54X6-TG-SB-L1

Configure Your Order

Select profile, grade, and length below to see live pricing

T&G

Select and Better is our standard grade

Length Guide

Available lengths: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22′

Estimated Shipping Weight
Weight per linear foot:2.67 lbs/LF
1' board:3 lbs

5/4x6 Massaranduba Tongue & Groove Decking — Complete Guide

Everything you need to know about t&g massaranduba decking

About 5/4x6 Massaranduba Tongue & Groove Decking

Massaranduba lumber, recognized for its exceptional durability and resistance to the harshest weather conditions, is an excellent choice for decking applications. Its robust nature, coupled with a tongue-and-groove profile, not only enhances structural integrity but also provides an aesthetically appealing finish. The tongue-groove design allows for easy installation and a seamless appearance, ensuring that deck boards fit snugly together while minimizing gaps that can collect debris and moisture.

  • Exceptional strength and durability
  • Weather-resistant; ideal for outdoor use
  • Tongue-groove profile enhances aesthetics and installation ease
  • Minimizes gap between boards, reducing moisture buildup

Key Benefits

Superior Strength

Massaranduba's high Janka hardness rating of 3190 classifies it among the strongest woods, ensuring that it can withstand heavy foot traffic and resist dents largely seen in softwood alternatives.

Exceptional Weather Resistance

Known for its natural resistance to moisture and insects, massaranduba is less prone to rot and will maintain its integrity through various environmental conditions, making it a reliable choice for outdoor applications.

Aesthetic Appeal

The tongue-and-groove profile not only serves a functional purpose in securing the boards together but also offers a clean, finished look for any decking project.

Technical Specifications

Janka Hardness

3190

Density

Approximately 1,000 kg/m³

Durability Rating

Class A (highly durable)

Dimensional Stability

Excellent dimensional stability, minimal shrinkage or swelling in outdoor conditions

Installation Guide

Difficulty:
Moderate

Key Tips:

  • Ensure proper ventilation between boards to allow for air circulation.
  • Maintain consistent expansion spacing for thermal movement.
  • Use stainless steel or coated screws to prevent corrosion.

Recommended Tools:

Circular saw
Drill/driver
Measuring tape
Level

Maintenance & Care

Cleaning

For routine cleaning, use a broom or leaf blower followed by a gentle wash with soap and water. Avoid harsh chemicals that could damage the wood's surface.

Finishing

Apply a UV protective finish or sealant every 2-3 years to maintain color and extend lifespan.

Weathering

Exposure to UV light can result in color fading; regular cleaning and maintenance can help reduce this effect.

Frequently Asked Questions

A 5/4x6 Massaranduba board weighs approximately 2.67 lbs per linear foot. Massaranduba has a density of about 65 lbs/ft³, making it one of the densest commercially available hardwoods. Always factor weight into your structural and shipping calculations.

Yes — Massaranduba is rated Durability Class 1 (Very Durable) and is naturally resistant to rot, decay, insects, and fungal attack without chemical treatment. It is naturally durable and performs exceptionally well in full exterior exposure including decking applications. While ground contact is possible, we recommend elevating Massaranduba boards at least 6" above grade for maximum lifespan.

Massaranduba outperforms composite in hardness (3,190 vs ~200 Janka), lifespan (up to 50+ years vs 25-30 years), and heat resistance. Unlike composites, Massaranduba won't melt, warp in extreme heat, or fade significantly. While initial cost is similar ($8-15/LF installed), Massaranduba costs less over its much longer lifetime. Composites do offer lower upfront maintenance.

Massaranduba requires minimal maintenance. Without treatment, it naturally weathers to an elegant silver-gray patina over 6-12 months. To maintain the original warm brown color, apply a UV-inhibiting penetrating oil (like Ipe Oil or Penofin) once or twice annually. Cleaning involves periodic washing with a mild soap solution. No sanding, staining, or sealing is required for structural durability.

Massaranduba is DIY-friendly with proper preparation. Key requirements: (1) Always pre-drill all screw holes — Massaranduba is too hard for direct screwing. (2) Use only 305 or 316 stainless steel fasteners — standard hardware will corrode and stain. (3) Face-screw with stainless steel trim-head screws. (4) Allow boards to acclimate on-site for 5-7 days before installation. A compound miter saw with a carbide-tipped blade is recommended.

A nominal 5/4x6 Massaranduba board has actual finished dimensions of 1" × 5.5" (25.4 x 139.7 mm). The "5/4x6" is the nominal (rough-cut) size — after kiln drying and precision surfacing, all hardwood lumber finishes slightly smaller. This is standard across the lumber industry, similar to how a nominal 2×4 softwood measures 1.5" × 3.5". Always use the actual dimensions (1" × 5.5") when calculating material quantities and coverage for your project.

We responsibly, legally, and ethically source all our Massaranduba. We work only with suppliers who follow responsible forestry practices with full chain-of-custody transparency. Note: We are not FSC certified. Massaranduba trees grow naturally in diverse tropical forests and regenerate well under managed harvest. The extremely long lifespan (up to 50+ years) means fewer replacements compared to softwood or composite alternatives, reducing long-term environmental impact.

Shipping & Delivery

Nationwide delivery: We ship to all 50 states via LTL freight, flatbed, or terminal pickup

Typical lead time: 5-10 business days for standard orders (custom milling may add 2-3 weeks)

Shipping estimate: Final freight cost calculated at checkout based on your location and order size

Rush service available: Contact us for expedited milling and shipping options