OSB 3 Sterling Board

Oriented Strand Board (OSB for short), or sterling board, is similar in many ways to plywood, with comparable flexibility and strength. It is relatively easily sealed against the elements and therefore makes for excellent internal or external building material. It is manufactured by compressing layers of wood strands and adhesives strategically to add to its strength.

The dimensions of a standard sheet of OSB are 2440mm x 1220mm (8x4) and they come in thicknesses of 9mm, 11mm or 18mm. There is also a specific type of OSB for flooring and roofing which comes in 2400mm x 590mm per sheet, and has tongue and groove finishing in order to help it fit together more smoothly.


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What is OSB3 Sterling Board?

OSB3 board – also known as sterling board – is an extremely versatile construction material which is steadily gaining popularity in the UK and around the world. 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. While it isn’t waterproof, OSB3 is resistant to moisture, making it superior to OSB2. Indeed, OSB3 is the most popular product of its kind on the market today. It has similar properties to plywood and the generally lower OSB price means it often represents better value to buy cheap OSB board than the more expensive plywood. 


What is OSB3 board used for?

Many contractors use OSB for roofing and when OSB is on the roof, it is generally used for roof sheathing, below the outer roofing system. It is also used for wall sheathing and frequently used for flooring. We have a special kind of OSB board for sale which is aimed specifically at flooring use, which has been carefully engineered to make it easier to lay and fit together. 

Is OSB3 sterling board environmentally friendly?

While very few building materials are completely environmentally friendly, OSB is one of the better ones and even the cheapest OSB board is more environmentally-friendly than plywood and conforms to the Forest Stewardship Council (FSC) as well as the Programme for the Endorsement of Forest Certification (PEFC). These certifications mean that the timber used to make OSB panels is sourced from legal and sustainable sources. Smaller, younger trees such as Aspen, Poplar or Southern Yellow Pine are used to make OSB than are used to make plywood, so in this sense, it is also more sustainable as older trees that have been there longer are left untouched during its production cycle.    

How much does OSB board cost?

When you are looking to buy OSB board for your project, cost is an important consideration.  The fact that you can find cheap OSB sheets for sale at less than the price of plywood makes it a winner in our book. As an OSB supplier, we know that even though the OSB for sale through our website is cheaper than plywood, it is of an excellent standard and will serve you well in your construction project. If we look at the OSB sheets for sale on our website, the price you will pay will depend on the thickness you require. 

Frequently Asked Questions about OSB Board

What does OSB board stand for?

OSB stands for Oriented Strand Board and this perfectly describes the process used to make it. The strands of wood are turned, or “oriented” to face the best direction to strengthen the board in each layer of the manufacturing process. This helps it to become an extremely strong load-bearing construction material and one which is in great demand today.

Is OSB3 board Waterproof?

We often get asked whether OSB is waterproof or “Can OSB board get wet”? And the answer is that while it is not completely waterproof, it is more water resistant than plywood and is easy to seal. In terms of how to seal OSB panel, good quality waterproofing solutions can be bought from most good hardware stores.

It is just a case of applying this to the surface that needs to be sealed 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?

When looking at the pros and cons of a product like OSB vs plywood or chipboard, it’s important to consider the application it is being used for. OSB boards are heavier than plywood, which that is why they make such a good load-bearing material for things such as flooring and wall sheathing. The strength of OSB panels is something that ensures it is a very popular choice for any and all such tasks.  

A main reason underpinning the strength of OSB board lies in the means of their manufacture. Layers of wood strips are placed strategically with the purpose of enhancing its strength. There may be 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.