By Abhijit Phadke
In India, when plywood shopkeepers, carpenters and interior designers talk about Commercial plywood what they usually mean to say is MR grade plywood.
There are different grades of plywood based on quality and characteristics, such as MR grade, BWR grade, Marine plywood etc. The acronym MR stands for Moisture Resistant, while BWR means Boiling Water Resistant.
While some people do club BWR grade plywood into the commercial type, for most people in the Indian plywood industry the term 'Commercial' means MR grade, while 'Waterproof' means BWR grade.
The important features of MR grade Commercial plywood are listed below.
1. It is an Interior grade plywood, meaning its for indoor use.
2. It is not waterproof. Though the word 'Moisture Resistant' (MR) can confuse many people into thinking that its waterproof, that is not the case. Being 'moisture resistant' is not the same as being 'water resistant'. While it is true that moisture resistant plywood can withstand some amount of moisture and humidity, it cannot be said to be waterproof. On the other hand, the exterior BWR grade plywood is waterproof.
3. In the case of Commercial plywood, Urea melamine formaldehyde resin is usually used for glueing the individual plies together. On the other hand, BWR grade is made from phenol formaldehyde, which is a synthetic plastic resin.
4. MR grade Commercial plywood is the most widely used type of plywood for making furniture for homes and offices. Drawing room furniture and paneling work, as well as bedroom furniture is almost always made using Commercial ply. However in those cases where the furniture is likely to get wet, using BWR grade ply is considered to be better.
5. The Indian Standards specification number for Commercial MR grade plywood is detailed in document IS:303