What are the options for 18 mm OSB boards?
The product has class 2 with SKU LT-4547 and class 3 with SKU LT-4546. According to EN 300, OSB/2 is for load-bearing use in dry conditions, while OSB/3 is for conditions with increased humidity, but not waterproof. The manufacturer and technical declaration are not specified in Shopify, so the class and performance values are checked on the delivered sheet.
Is 18 mm OSB suitable for a load-bearing floor on joists?
OSB can be used in floor systems, but 18 mm thickness alone does not determine the allowable span or load. The class, main axis direction, sheet size and edge support, joint support, and design loads are needed. The choice should follow the factory table and structural verification. Do not accept a universal joist spacing from a similar product.
When is 18 mm OSB more suitable than 15 mm or 22 mm?
Eighteen millimeters is the intermediate catalog thickness between 15 and 22 mm, but the correct choice depends on load, support span, deflection, moisture, and the requirements of the flooring or roof. Exact comparative values are lacking. If the project specifies 18 mm, substitution up or down should be done after checking weight, fasteners, levels, and declarations of the specific boards.
What spacing can supports have under 18 mm OSB?
There is no single confirmed value for this product. The allowable spacing depends on the manufacturer, class 2 or 3, main axis, number of spans, loads, limit deflection, and edge connection method. Shopify does not contain the necessary table. The designer must use the declaration and structural data of the delivered board before determining the joist or batten spacing.
How does moisture affect 18 mm OSB boards?
OSB is a hygroscopic wood material and changes dimensions with humidity. Class 3 has improved resistance to humid conditions compared to class 2, but is not intended for permanent wetting. Before installation, the sheets are acclimated and protected from water, and joints and edges are executed according to the manufacturer. The nominal 18 mm thickness does not necessarily remain unchanged with improper storage.
What should be known about the weight and handling of 18 mm OSB?
The weight of a sheet cannot be calculated without its length, width, and density, which are missing from the product. Do not plan unloading based on approximate weight from another brand. Before delivery, request the format, number of sheets per pack, and pack weight. Boards are handled and stored so that edges and flatness are not damaged or bent.
