The Ultimate Guide to Oriented Stand Board (OSB 3)

If you've ever found yourself beginning construction on a new home (or are merely considering it), you likely can't catch a break from those in the know singing the praises of OSB 3 Boards.

Sounds industrial, doesn't it?

If you're not sure what OSB 3 boarding is and what its benefits are, you're not alone - we've helpfully broken down anything and everything you might need to know about this wonderful resource.

 

What is OSB?

 

OSB stands for oriented strand board and is a type of construction material. While vaguely similar to chipboard, all oriented strand boards use longer, coarser pieces of wood - this increases mechanical strength and resistance to humidity but a smooth surface is sacrificed.

 

OSB is an engineered form of chipboard, produced by the addition of adhesive to strands of wood of varying thicknesses to form layers which are compressed onto one another. This both ensures a consistent density and is done carefully such that there are no open gaps - allowing the board to be waterproof and withstand humidity.

OSB is both cost-effective and sustainable - it can be made from nascent saplings, many of which come from British FSC certified forests. It's usually bought in sheets - up to 9ft tall - meaning you can sheathe an entire wall with singular sheets oriented vertically. OSB up to any size can be manufactured, however.

Note that plywood is generally limited to 8 to 10 feet.

What is OSB used for?

 

There are multiple uses of these boards. OSB is, in most cases, used for installing floors, walls, and roofs. Quite often, this material is used as a replacement for plywood. So, if you are installing shelves, ceiling, cabinets, or planning to make some furniture, OSB is a great choice.

 

Benefits

 

There are many advantages to using OSB. First of all, the materials from which these boards are made is extremely strong and durable and that’s why these boards have an extremely high load-bearing capacity in construction. What is also important to note is that micro veneer, together with binder additives, makes these boards extremely technically capable.

 

In addition to the indisputable quality, the use of OSB panels will contribute to giving your home a more natural look. This is the case when we talk about walls and floors, as well as furniture made from these boards.

 

Another benefit of using these boards is durability. This investment will pay off in the future.

 

Also, if you are an environmentalist, know that you have done a good deed by using OSB. The use of natural materials instead of artificial ones is good for the environment.

 

As previously mentioned, OSB has a consistent density throughout - and this means it has soundproofing properties.

 

Due to its method of manufacture, every sheet is very similar (if not identical) - allowing for ease of use when making floors and work in other large-scale projects.

 

Drawbacks

 

Well, we have to say that there is one reason that can be pointed out and that is the price of these boards. The OSB 3 boards, unlike the previous variants of OSB boards, are a shade more expensive. However, the benefits you will receive are much greater and that quality justifies the price. After all, you don't build a house every day.

Other cons include the following:

  • OSB's materials are held together with resin binders and wax. This wax can make it more difficult to stick this to some types of flooring directly to the OSB subfloor, requiring the installation of a plywood or cement board underlay;
  • OSB is heavier than plywood, weighing about 1kg per sq. ft. A 4x8 ft sheet of OSB weighs about 35kg;
  • Once waterlogged, OSB is slow to dry - potentially delaying a project;
  • Once swollen, OSB will not compact to its original size;
  • Base materials for making OSB - poplar, aspen, and the like - are rot-prone woods. This means that the resin and wax additives do most of the work of keeping the material from rotting away;
  • Nails pull out more readily from OSB than plywood - potentially an unfavourable property when attempting to nail down flooring.

 

 

Strength

 

Oriented strand boards are extremely strong, solid, and durable - owing to the method used to manufacture them, which, as before, compresses layers of long, coarse wood upon each other.

You can be sure that these boards are much stronger than all the others currently on the market.

 

 

Outside use

 

Previous variants of OSB were not the most optimal choice for use in outdoor facilities. External factors such as rain, wind, increased humidity, and the sun's rays were known to have consequences. However, the latest variant of OSB, OSB 3, is resistant to all these external influences.

OSB Grades - Which do I want?

 

Not every type of OSB is suited to every purpose. To help us differentiate, the European EN 300 standard defines each grade based on their mechanical performance and relative resistance to moisture.

Utilisation classes (UC) exist - class 1 signifies it is suitable in dry conditions only, whereas class 2 means that it is suitable in both dry and humid areas.

OSB panels are assigned to four different grades:

OSB/1

This covers general-purpose, non-load bearing panels for interior fitments and furniture in dry conditions. This grade is not sold in Germany. (UC1)

OSB/2

These panels are very strong and may therefore be used for loadbearing purposes where they will remain dry. (UC1)

OSB/3

Also for loadbearing purposes, but as these panels are made with water-resistant binders they may also be used in humid conditions. (UC2)

OSB/4

This classification designates heavy-duty boards for use in both dry and humid conditions. (UC2)

 

The rule of thumb is that panels of higher grades are stronger and more resistant to moisture. In addition, the standards define the meanings of the words 'dry conditions' and 'humid conditions' in context of OSB:

1: Dry conditions

This refers to completely enclosed, heated spaces. The average equilibrium moisture content is about 12% at an ambient temperature of 20°C, with relative humidity of 65% which stays constant for almost the whole year.

 

2: Humid conditions

This refers to roofed-over (but open) constructions which are not directly exposed to the elements. Solid wood components reach an average equilibrium moisture content of about 20% at an ambient temperature of 20°C and relative humidity of predominantly 85%. These values may only be exceeded during a few weeks each year, however. For engineered wood products, the value may not be greater than 18%, which is not due to stricter requirements but rather to the fact that engineered wood has a lower equilibrium moisture content under conditions that are otherwise the same.

 

It is important to take the climatic conditions at the installation site into account. For example, loadbearing boards used in the enclosures of indoor swimming pools can develop an equilibrium moisture content greater than 12% owing to the high relative humidity of the air, despite the fact that an enclosed and heated space is involved.

You might look at this scenario and its conditions and assume a grade at utilisation class 1 would still be appropriate - but as the conditions at the installation site will not remain constant throughout the useful life of the loadbearing structure, a higher grade at utilisation class 2 is recommended.

 

OSB/3 and OSB/4 boards must always be shielded from the weather. This means that, while they may definitely be used as structural building elements, they must be additionally protected by some kind of covering, such as a curtain wall.

 

DIN 68800-2:2012-02 defines “protected from the weather” as meaning permanently and effectively covered or located beneath roofing or an overhang inside a line drawn inward and down at a 60% angle from the outer edge.

 

To prevent damage, it’s vital to make sure that at the time of installation, wood has a moisture content which is already very close to the equilibrium moisture content that will develop over time. Especially components intended for later use in class 1 or 2 applications must be protected during transport and installation to prevent them from being directly exposed to the elements and absorbing large amounts of moisture.

 

Durability

 

If you decide to use OSB, you can be sure that it won't falter under pressure. Because it is resistant to both internal and external conditions, and it is an extremely strong material, durability is guaranteed.

 

Roofing usage

 

When planning to make roofs, people usually opt for materials such as metal, wood, slate or tiling.

Oriented strand boards have been largely ignored as a viable option because recent variants have not been resistant to external factors such as rain, snow, and humidity in general. However, this latest variant of OSB, OSB 3, is resistant to all these conditions.

Specifically designed for outdoor use, OSB 3 uses certain additional waterproof materials that ensure your roof is well protected.

 

 

Homebuilding usage

 

As before, when it comes to building your home, these boards can fulfil many different roles. They're perfect for constructing a roof, ceilings, walls, furniture, and of course, flooring.

The decision to choose OSB 3 allows you to sleep in smug comfort knowing you have chosen the best, most cost-effective resource for building your home.

 

I'm sold! Where can I get it?

 

All that's left to do is to find what you need for your project. If you’re still unsure about what you need, you can always contact us to help you decide, but if you do know what you want, you know where to get it.

You can always trust ABC Depot to supply you with the best tools and materials for the job. ABC Depot offers a bulk-buy discount on OSB 3 Boards and other sheet materials - shop OSB 3 Boards with us today!



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