Types of Bluestone Patios
A question that often comes up when discussing bluestone patios are the different varieties of bluestone pavers. To the untrained eye they may all look the same, but, there are actually a number of differences that effect the cost, appearance, and installation methods.
Natural Cleft Bluestone:
Natural cleft bluestone describes bluestone that has been split or cleft into layers during the quarrying process. Bluestone is a sedimentary stone, meaning that is comes from sediment that has been fused together deep underground from the enormous weight and pressure from above. As it was formed by layers of sediment, it is often possible to find cracks or lines of de-lamination in the stone and split it into slabs. These slabs are then cut into rectangles to make the natural cleft bluestone pavers you see today.
As it is naturally split, the bluestone pavers have some irregularities. The surface of the stone will have more bumps and texture, and each stone will vary in thickness somewhat. Natural cleft bluestone also tends to have a range of colors of blue, gray, purple, and rusty orange.
The quarrying process of natural cleft bluestone takes less saw cutting and makes natural cleft bluestone less expensive than other bluestone. The varied thickness and irregular surfaces, however, make it more labor intensive to install.
Thermal bluestone is formed deeper within in the earth than natural cleft bluestone. With more weight and pressure above, the stone has fewer fault lines and must be broken off in big chunks and then sawn cut into layers. The saw cut leaves a very smooth, unnatural surface which then must be re-textured. This texturing is the ‘thermaling’ process which gives its name. The stone is wet down and then heated with a super hot flame until the surface flakes off, exposing the natural roughness of the stone.
Cutting bluestone takes a lot of machinery and expensive diamond blades and so thermal bluestone is more expensive to produce, but, the stone is very uniform in thickness. This makes the installation and leveling process less labor intensive than natural cleft bluestone.
Irregular Bluestone (Flagstone)
Irregular bluestone, also called “stand-up bluestone” or “flagstone” is naturally cleft bluestone that has not been cut into rectangles.
Irregular bluestones will vary greatly in shape, size, and thickness. They need to be cut and shaped to fit together, and then leveled one by one. There is a range of joint size that can be achieved depending on the desired look and cost. Irregular bluestone cost less in material but is much more labor intensive to install than other types of bluestone patios.
There are various options for bluestone patios depending on your style preference and budget. Please contact us with any questions or to receive a quote.