OSB for the attic – what is worth knowing?

OSB is a very popular material used to finish an attic. What is worth knowing about OSB? Why is it worth using it to finish the attic?

What is OSB?

OSB (oriented strand board) is a highly compressed wood-based material. It is usually composed of up to 90% spruce or pine chips. It is widely used in construction.

For board production chips of similar size are used. They are glued with special resin and then pressed under pressure at high temperature. A single panel consists of three layers. This makes the material resistant to bending

What types of OSB are there?

There are several grades of OSB, which differ in their resistance to moisture and durability:

• class 1 and 2 are the most sensitive to moisture and are recommended only for dry areas;
• class 3 – works well both indoors and outdoors. They can be used in rooms with increased humidity;
• class 4 – has the highest resistance to moisture. They are mainly used to make framework constructions.

Which OSB panels to choose for the attic?

OSB 12 mm thick is most often selected for attic walls. For the floor, a 22 mm thick board is recommended. If the floor will be heavily loaded, you should choose 25 mm thick board.

OSB flooring – what should be remembered?

If you want to make an OSB floor in your loft, you should remember that it should be fixed on joists. It is worth choosing boards with tongue-and-groove milled edge or with a straight edge. When you use boards with a straight edge, you have to lay them with their longer edge against the joists. Leave a 12 mm gap between the boards and the wall. This prevents the boards from pushing against each other and the floor from being damaged.

Nails or special screws should be used for fixing the boards to the joists. They should be 2.5 times longer than the board thickness. They should be screwed every 15 cm, in places where the board is joined. On supports, screws should be used every 30 cm.

Why is it worth finishing the attic with OSB?

Finishing an attic with OSB is a very cheap and convenient solution. Walls made of the board can be finished in any way you like, e.g. with ceramic tiles, paint or wallpaper. OSB is very resistant to bending and stretching. Thanks to this you can finish walls and floors in the attic with them.

Main photo: Anthony Shkraba/pexels.com