Polished Concrete Floors for Basements

Polished Concrete Basements
Beautiful Floors for Basements and Damp Floor Areas

By Phil Evans
Titus Restoration Services, Inc.
Woodstock, Georgia
678-494-6893
www.titusrestoration.com
Serving the U.S and Carribean Islands

In our headquarters service area, Atlanta and the southeast, many residences have damp floors and many other buildings are plagued by moisture vapor transmission through the concrete floor slab. Moisture vapor transmission is particularly troublesome along the coast lines and southern states with sandy soils, high water tables, or water laden muck soils. This moisture can contribute significantly to failed flooring and indoor air pollution if left unchecked. If you are contending with a concrete floor that is damp there are solutions.

Titus is a concrete polishing contractor. We offer polished concrete floors or dyed and polished concrete basement floors as a healthy solution for damp concrete floors. These floors are often characterized by moldy, mildewed, musty carpets or floor covering. If you suffer from asthma, polished concrete floors may simply be the best floor finish for a basement. Read on because we want to provide you with some basic information to help you make better decisions and explain things to look for in other floor finishes.

First of all, it helps to understand some of the basics. Moisture vapor transmission through a concrete slab happens for two (2) primary reasons. Here are a couple of examples: Example 1) Turn on the air conditioner, the ambient atmosphere dries, and moisture migrates through the concrete to equalize itself. The movement of this moisture through the concrete carries salts from the concrete. These salts form on the surface and are called efflorescence. Example 2) The second cause of moisture in a basement is hydrostatic pressure. Basically, hydrostatic pressure can be calculated as one (1) pound hydrostatic pressure for every two (2) feet the basement is below grade (an 8 foot below grade basement has 4 pounds of hydrostatic pressure at the floor).

In the event there is hardwood installed over the concrete slab and the slab is emitting too much moisture it could swell and buckle. Any hard surface floor applied with a mastic is in jeopardy due to the high pH of the efflorescence deteriorating the mastic. Painted concrete floors also fail either due to saponification caused by efflorescence or by lifting caused by hydrostatic pressure. Wet concrete floors are a major problem for floor coverings.

In the event there is carpet installed over the concrete slab and the slab is emitting too much moisture it cause mold or mildew. Any carpet applied with mastic (such as commercial carpeting or carpet squares) is also in jeopardy due to the high pH deteriorating the mastic and carpet. This deterioration released harmful VOC contributing to indoor air polution and compounding problems for those with respiratory illnesses.

In today’s residential building trends, basements are often finished as part of the living quarters and have higher ceilings. It is also typical that they are air conditioned. Combine the drier air of air conditioning and the increased hydrostatic pressure because the basement are deeper and the result is that more moisture vapor passes through the concrete slab and back into the house. As the moisture vapor passes through the slab and so do more salts from the concrete, leading to more efflorescence, more moisture in the carpet, and higher the utility bills from the air conditioning trying to remove it! So how do you put an end to this circuitous process where the air conditioning system creates more work for itself?

We have two (2) answers. One (1) is to seal the floor with a moisture blocking epoxy. This typically requires steel shot blasting of the concrete slab followed by multiple coats of moisture tolerant epoxy coating. Many such systems exist today and offer protection of up to 25 pounds per square foot of moisture vapor transmission. These coatings can then be covered with cementitious overlays, tile, hardwoods, or practically any other floor material. Answer two (2) is to polish the concrete. This is by far the most economical and better solution.

Polishing concrete floors works like water repellent fabrics (Gortex®), the substrate remains breathable but the top portion of the slab is denser and moisture vapor is greatly reduced and passes through it more slowly. Polished concrete eliminates the moldy, mildewed smell associated with other floor finishes in damp areas. When you use polished concrete there is no coating or other hard surface flooring to fail. Many who have asthma or other respiratory illnesses also prefer polished concrete floors to other hard surface flooring as they are easier to clean and keep dust free.

We at Titus believe polished concrete floors are the best floor finish for asthma sufferers (or someone suffering from allergies or other respiratory illnesses). Polished concrete is an asthma friendly floor and a healthy choice.