1x2 Cumaru Shiplap Siding board profile diagram
Siding

1x2 Cumaru Shiplap Siding

This 1x2 Cumaru siding board (Shiplap profile) offers unmatched exterior cladding longevity, backed by Cumaru's 3,330 Janka hardness and a natural lifespan of up to 50+ years. The overlapping shiplap profile sheds water naturally and creates a classic, weather-resistant look for exterior cladding and accent walls. In stock and ships nationwide — order 1x2 Cumaru siding boards online or call 1-844-674-4455 for expert guidance.

1 x 2(0.75"×1.5" actual)[19.0mm × 38.1mm]
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Ships Nationwide
SKU: CUMA-1X2-SHIP-SB-L1

Configure Your Order

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

Shiplap

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:0.55 lbs/LF
1' board:0.6 lbs

1x2 Cumaru Shiplap Siding — Complete Guide

Everything you need to know about shiplap cumaru siding

About 1x2 Cumaru Shiplap Siding

Cumaru lumber, specifically in a shiplap profile and 1x2 nominal (0.75x1.5 actual) size, is an exceptional choice for exterior siding and cladding applications. Known for its remarkable dimensional stability and weather resistance, Cumaru is a dense hardwood that performs excellently in various climatic conditions. The shiplap profile enhances the aesthetic appeal by creating distinct shadow lines and allows for easy installation in horizontal or vertical orientations, providing versatility in design applications.

  • Dimensional stability ensures minimal warping and shrinking over time.
  • Excellent weather resistance protects against moisture and extreme temperatures.
  • The shiplap profile facilitates quick, efficient installation while enhancing visual interest.

Key Benefits

Durability

Cumaru's high Janka hardness rating means it is resistant to dents and scratches, making it ideal for high-traffic areas and harsh environments.

Visual Appeal

The rich, warm tones and unique grain patterns of Cumaru enhance the aesthetic value of any building, providing a natural, premium look.

Low Maintenance

Once installed, Cumaru requires minimal upkeep, retaining its beauty and integrity without frequent refinishing.

Technical Specifications

Janka Hardness

3330

Density

65 lbs/ft³

Durability Rating

Class 1 (Very durable)

Dimensional Stability

Highly stable, resistant to movement and deformation.

Installation Guide

Difficulty:
Moderate

Key Tips:

  • Ensure proper spacing for expansion due to humidity.
  • Use stainless steel or coated fasteners to prevent corrosion.
  • Implement drainage and ventilation strategies for optimal performance.

Recommended Tools:

Miter saw
Drill
Measuring tape
Level

Maintenance & Care

Cleaning

Clean with a mild detergent and water; avoid harsh chemicals that can damage the wood.

Finishing

Apply an appropriate wood preservative and UV blocker to maintain color and protect against weathering.

Weathering

Cumaru naturally weathers to a silver-gray patina if left untreated, which may be desirable for some applications.

1x2 Cumaru Shiplap Siding — Frequently Asked Questions

A 1x2 Cumaru board weighs approximately 0.55 lbs per linear foot. Cumaru has a density of about 68 lbs/ft³, making it one of the densest commercially available hardwoods. A 12-foot 1x2 Cumaru board weighs approximately 6 lbs. Always factor weight into your structural and shipping calculations.

1x2 Cumaru siding has an expected service life of up to 50+ years when properly installed. This is 3-5× longer than pressure-treated pine and 2-3× longer than cedar. Cumaru achieves this exceptional longevity through its 3,330 Janka hardness and Class 1 durability rating, providing built-in resistance to rot, decay, insects, and fungal growth without chemical preservatives.

1x2 Cumaru siding pricing varies by profile, grade, and board length. Select and Better grade boards typically range from $4-$12 per linear foot before shipping. While the upfront cost is higher than pressure-treated lumber, Cumaru's up to 50+-year service life makes the lifetime cost per year significantly lower. Use the configurator above for exact pricing, or request a custom quote for large orders.

Yes — 1x2 Cumaru wood siding outperforms composite in hardness (3,330 vs ~200 Janka), lifespan (up to 50+ years vs 25-30 years), and heat resistance. Unlike composites, Cumaru won't melt, warp in extreme heat, or fade significantly. While initial cost is similar ($8-15/LF installed), Cumaru wood decking costs less over its much longer lifetime. Composites do offer lower upfront maintenance, but Cumaru's natural beauty and durability make it the superior long-term investment.

Cumaru is widely considered one of the best woods for 1x2 siding boards. With a 3,330 Janka hardness rating, Class A fire-rated certification, and up to 50+-year lifespan, Cumaru (Brazilian Teak) outperforms nearly every other commercially available wood species. Other excellent options include Cumaru (Brazilian Teak) and Massaranduba (Brazilian Redwood), but Cumaru remains the industry benchmark for premium outdoor hardwood applications.

Cumaru 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.

Cumaru is DIY-friendly with proper preparation. Key requirements: (1) Always pre-drill all screw holes — Cumaru 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 1x2 Cumaru board has actual finished dimensions of 0.75" × 1.5" (19.0 x 38.1 mm). The "1x2" 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 (0.75" × 1.5") when calculating material quantities and coverage for your project.

We responsibly, legally, and ethically source all our Cumaru. We work only with suppliers who follow responsible forestry practices with full chain-of-custody transparency. Note: We are not FSC certified. Cumaru 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

Alternative Siding Option

This same Cumaru 1 x 2 is also available in a different siding profile:

Rainscreen

Designed for rainscreen clip systems with ventilation gap

1x2 Cumaru Shiplap Siding — Complete Buyer's Guide

Cumaru, also known as Brazilian Teak, is a premium tropical hardwood sourced from Amazon Basin, northern South America (Brazil, Venezuela, Guyana). With a Janka hardness rating of 3,330 lbf and a density of 65 lbs/ft³, Cumaru is classified as Class 1 - Very Durable — one of the most durable commercial lumber species available. The heartwood exhibits light to medium brown with reddish tones with interlocked grain, medium to coarse texture, creating a striking natural appearance that improves with age.

Why Choose 1x2 Cumaru Wood for Your Siding?

As exterior cladding, Cumaru siding provides a weather-tight barrier with exceptional impact resistance. The dense grain resists dents, hail damage, and woodpecker damage far better than cedar, pine, or fiber cement alternatives. Properly installed 1x2 Cumaru siding delivers a service life of 50+ years with minimal maintenance — an optional annual oil treatment preserves the original color, or you can let the Cumaru wood weather to a distinguished silver-gray patina. Cumaru carries a Class A - Low flame spread, making it suitable for wildfire-prone regions where code-compliant materials are required.

The 1x2 shiplap profile creates an overlapping joint with a distinctive shadow line between boards. Popular for siding, accent walls, and architectural cladding applications. All Cumaru lumber is available in Select and Better grade with lengths ranging from 4′ to 20′. For detailed step-by-step instructions, consult our Cumaru installation guide. Long-term care recommendations are covered in our Cumaru maintenance guide.

1x2 Cumaru Siding — Installation & Coverage Specs

  • Recommended joist spacing: 16" on center for 1x2 boards (0.75" actual thickness)
  • Fastener placement: Secure per profile requirements, one fastener per joist minimum
  • Board weight: A 12-foot 1x2 Cumaru board weighs approximately 6 lbs (0.53 lbs/LF)
  • Coverage: Each 12-foot 1x2 board covers 1.5 sq ft of siding surface (1.5" face width)
  • Pre-drilling required: Always pre-drill in Cumaru — the 3,330 lbf hardness prevents direct screwing

Janka Hardness

3,330 lbf

Service Life

50+ years

Durability

Very Durable

Fire Rating

Class A

1x2 Cumaru Siding — Frequently Asked Questions

1x2 Cumaru siding has an expected service life of 50+ years when properly installed and maintained. This is 3-5x longer than pressure-treated pine and 2-3x longer than cedar. Cumaru achieves this exceptional longevity through its natural density (Janka hardness: 3,330 lbf) and Class 1 durability rating, which provide built-in resistance to rot, decay, insects, and fungal growth — all without chemical preservatives.

Use 305 or 316 stainless steel screws for all Cumaru installations — never use galvanized or coated deck screws, which will corrode and stain the wood. Pre-drill every hole using a countersink bit sized for your screw. For 1x2 boards, place screws approximately 1" from each edge and 3/4" from board ends. A combination drill/driver with a clutch setting prevents over-driving into this extremely hard wood.

1x2 Cumaru siding pricing varies by profile, grade, and board length. 1x2 Shiplap boards in Select and Better grade typically range from $4-$12 per linear foot before shipping. While the upfront cost is higher than pressure-treated lumber, Cumaru's 50+ years service life makes the lifetime cost per year significantly lower. Use our online configurator above to see exact pricing for your selected options, or request a custom quote for large orders.

Related Cumaru Products & Resources

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