Portland cement Type 1
A general-purpose cement for ordinary construction where the concrete is not exposed to soil or water containing sulfates. It is used in structural concrete, masonry and most general work.
Portland cement Type 2
It has moderate sulfate resistance and releases less heat than Type 1 while setting. It is a common choice for foundations and parts in contact with soil or water containing sulfates, and for mass concrete.
Portland limestone cement
In this cement, part of the clinker is replaced with ground limestone. It is easy to work with and is used for mortar, plaster and much general building work. Its production uses less clinker, which is better for the environment.
What does 42.5 mean?
This number is the strength class of the cement: the minimum compressive strength of its standard mortar after 28 days, in megapascals. Common classes are 32.5, 42.5 and 52.5.
Which one to choose?
The final choice depends on the soil and water conditions on site and on the structural design, and is best made with the advice of the design or supervising engineer.