4 Sustainable Qualities of Mineral Wool Insulation

Minimizing a building’s energy demand, or maximizing its efficiency, is critical to green building.

And while there are many ways to achieve energy efficiency, properly insulating your building envelope is by far one of the most important tactics.

There are as many types of insulation as there are ways to insulate a building... From cellulose (paper), to fiberglass to mineral wool to spray foam, each insulation has its pluses and minuses. Spray foam insulation has lately become a buzzword for sustainability because it can be applied quickly and inexpensively, leading to many businesses popping up marketing "sustainability", even though some question the safety of spray foam.

However, today’s spotlight is on one of the best, in terms of sustainability: Mineral Wool by Roxul. For its safety and insulative value, mineral wool is ahead of the pack.

ROXUL, Inc. is one of the leading manufacturers of mineral wool. As a company, it strives for sustainability, aiming to manufacture products that significantly reduce the energy load of buildings.

It’s manufacturing process is also monitored to keep environmental impact to a minimum. In the process of manufacturing rockwool the company:

- Controls emissions, and uses its own products as recyclable filters that are added back into the production process
- Reuses water sourced from storm water, with a total consumption reduction of 50%
- Uses products that are made with up to 40% recycled materials
- Captures heat generated in production which is recovered and used to heat factories and warehouses
- Has cut energy usage with energy efficient lighting

A subsidiary of Rockwool International, Roxul produces high quality mineral wool. Possessing the characteristics of typical wool insulation, including non-directional fiber orientation, mineral wool also has all the added benefits of stone, as described below.

The process of manufacturing Roxul mineral wool begins with combining volcanic rock, slag and coke in a smelting furnace. The combination melts into a spinning machine where the wool is spun. At this point, small amounts of binder and oil are added. The wool is collected on a belt conveyor and adjusted as necessary for proper structure and density.

Cured wool is then cut and packaged, and any off gassing is filtered before being released through chimneys. Any additional waste material is recycled. This process creates a material that possesses many qualities that are sought after in building insulation.

1) Water Repellent

Roxul mineral wool does not absorb water, a particularly desirable feature as it prevents unwanted organic growth in the insulation layers of a building, also preventing rot. This characteristic also helps prevent mineral wool from sagging, maintaining its insulative value throughout its lifespan. It is also oriented in such a way that water drains away from walls and pipes.

2) Sound Absorbent

Because of its nondirectional structure, Roxul mineral wool is denser than other insulation products. Thus, airflow is reduced, as is sound transmission. The denser the material, the greater sound attenuation. Products such as rigid mineral wood boards have among the highest sound proofing capabilities.

3) Fire Resistant

This is potentially one of the most important features of mineral wool: rock doesn’t burn. Roxul mineral wool can withstand temperatures up 2150 F, and is non-combustible.

Greater fire resistance in insulation materials means potentially slower spreading fires, greater occupant escape time, potentially saving lives. Being naturally fire resistant, mineral wool does not require additional flame retardants, which have been connected to negative impacts on human health.

4) Energy Saving

Heating and cooling account for approximately two-thirds of a building’s energy consumption. Properly insulating a building can result in a significant decrease in energy demand and wasted energy.

Mineral Wool has a high R-value, providing superior insulation.

Roxul produces high quality insulation that contributes to sustainability during production and throughout the life of the product.