OSB 3 Sterling Board

(8 Products)

Designed to withstand the toughest (humid) conditions, Oriented Strand Board (OSB for short) is exactly as it sounds; these boards comprise 'oriented strands' (wood fibres and adhesives compressed in opposing orientation) to achieve an excellent load-bearing and attractive wood patterned finish board. The finished product is performatively similar to softwood plywood, with comparable flexibility and strength. Purposed to excel in floor, wall and roof applications, OSB3 comes in thicknesses: 9mm, 11mm or 18mm.

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What is OSB3 Sterling Board?

OSB board – also known as sterling board – is an extremely versatile engineered wood sheet material. 

In terms of its appearance, OSB boards typically feature a particoloured and rough surface due to the fact that the outer wood strips are laid in a criss-cross manner to enforce the product's strength and durability. 

This strength lends itself to OSB3's performative superiority over its sister board OSB2. While Class 2 OSB can only be used for non-load bearing applications in dry conditions, OSB3 can be used for structural, load-bearing uses in humid conditions. 

What is OSB Wood Sheet Used For?

Many contractors use OSB boards as a structural panel for roofing, generally roof sheathing, below the outer roofing system. 

It can also be used as sheathing materials on walls, floors, ceilings and structural elements.

We recommend using OSB3 in the following structural applications: 

  • Wall sheathing 
  • Roof decking
  • Flooring applications
  • Signboards
  • Furniture and concealment applications


At Materials Market, we stock a specific type of OSB board for flooring and roofing which comes in 2400mm x 590mm per sheet, and has tongue and groove finishing in order to ensure a perfect, snug fit. 

OSB3 Board Benefits & Key Features

  • Relatively easily sealed against the elements - suitable for interior or exterior use
  • Resistant to moisture - making it superior to OSB2
  • Standard OSB sheet dimensions: 2440mm x 1220mm (8x4) 
  • Superb load-bearing properties
  • Durable building board
  • Cost-effective alternative to plywood

Frequently Asked OSB Board Questions

Frequently Asked Questions about OSB Board

What Does OSB Board Stand For?

OSB stands for Oriented Strand Board, which perfectly summarises its manufacturing process. The strands of wood are turned, or “oriented” in opposing directions to strengthen the board layer by layer then fixed together using UF glue (Urea Formaldehyde). 

The result is an extremely strong load-bearing construction material that creates rigidity and offers excellent cross-dimensional stability. 

Is OSB3 Sterling Board Environmentally Friendly?

Yes, OSB3 is much more eco-friendly than the majority of plywood materials on the market. OSB3 conforms to the Forest Stewardship Council (FSC) as well as the Programme for the Endorsement of Forest Certification (PEFC), meaning that the timber used to make OSB boards is sourced from legal and sustainable sources. 

What's more, OSB board utilises timber from smaller, younger trees such as Aspen, Poplar or Southern Yellow Pine, meaning older trees are left untouched during their production cycle.    

How Much Do OSB Wood Sheets Cost?

No matter the project, no matter the material, cost is always an important consideration.  The fact that OSB is generally cheaper than plywood makes it a winner in our book. Although it is markedly less in price, it is of an equal and excellent performative standard. 

In summary, the price you end up paying will ultimately depend on your chosen thickness. 


Is OSB3 Board Waterproof?

Whilst it's not entirely waterproof, OSB is water-resistant and can be sealed to further enhance its moisture performance. 

It's as simple as applying a sealant to the surface that requires protection against the elements. A paintbrush should be used to apply the waterproofing solution and it may take 12-14 hours to dry completely. 

An important thing to remember is that the OSB board should be cut to size before being sealed as any newly cut edge can potentially allow water to come in, if not appropriately sealed. 

To ensure the waterproofing has worked, it is prudent to pour water on the newly waterproofed surface after it has dried and wait a few hours to determine whether the water has managed to get through the waterproof barrier or not.

Is OSB Sterling Board Stronger Than Plywood?

OSB boards are heavier and stronger than plywood, hence why it is the preferred choice in applications where load-bearing is a priority, such as flooring and wall sheathing. 

OSB's strength lies in the means of its manufacture. Layers of wood strips are placed strategically with the purpose of enhancing their strength - potentially up to 50 layers in a single sheet! 

It is a testament to the strength of OSB3 as a building material that it is now used in around 70% of all home flooring in North America.

Can OSB Sterling Board Be Painted?

OSB Board can indeed be painted and this can add to the level of waterproofing on offer as the paint can shield the wood further from water ingress. 

It is important to note that if paint is being used, the waterproof sealant should be used on top of the paint, once it has dried as paint is not a substitute for an adequate sealant but can act as an additional barrier to water once the sealant has been correctly added.

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