Blackbutt Closed House Stair String (pair)

30mm Closed House Timber Stair String (pair)

Elevate your staircase with our precision-machined 30mm thick solid timber closed house string, expertly crafted for strength, accuracy, and a clean traditional look in Queensland homes. For custom floor finishes or non-standard requirements, see our stair configurator to order custom strings. These strings are sold as a pair and delivered as a left-hand and right-hand string together.

Dimensions & Profile:

• Thickness: 30mm
• Going: 240mm or 250mm
• Rise options: 170mm, 175mm, 180mm, 185mm or 190mm
• Upper and lower finishes set to 12mm – can be packed up or cut down on site to suit finished floor levels
• Precision-machined housings and wedge pockets designed to perfectly suit our 30mm treads, 18mm risers, 30mm Nosing (110mm Wide) and matching wedges

This string is made specifically for closed house (housed) stairs — the traditional enclosed style where the ends of the treads and risers are fully let into the string. It works equally well as a wall string or outer string and pairs perfectly with our 30mm Standard Timber Stair Treads, 18mm Timber Stair Risers, and purpose-made wedges for a tight, secure fit.

Perfect for both new builds and renovations, the 30mm construction delivers solid performance in family homes while giving a neat, continuous side profile that suits contemporary, coastal, or traditional designs.

Key Benefits:

• Easy assembly with accurately cut housings and matching wedge pockets for a tight, squeak-free joint
• Smooth, sanded surfaces ready for your choice of stain, oil, or clear finish

All products are delivered raw, pre-finished sanded to 100 grit.

Blackbutt, a premium Australian native hardwood (Eucalyptus pilularis), boasts a clean, uniform appearance with pale golden-brown to straw tones and a straight, even grain—occasionally accented by subtle gum veins for added rustic charm. Exceptionally durable and fire-resistant, with high density and strength, Blackbutt excels in high-traffic areas and is ideal for stair components that demand longevity and low maintenance. Its neutral palette complements contemporary and coastal  interiors, while its natural toughness makes it suitable for treads, stringers, risers, and handrails that stand up to everyday family use.