In the age of DIY, many homeowners are looking to improvise on repair jobs to save some money. A common waterproofing solution advised on DIY blogs is the use of plastic sheets as a vapor barrier in your basement.
The Material
You cannot use a plastic sheet as a vapor barrier because of what the material is made of. Real vapor barriers are not made of the same plastic as store-bought sheets. They are made of polyethylene, a material that is molecularly denser than normal plastic. Because of its density, a real vapor barrier is better at blocking off smaller particles like water vapor.
Plastic does not have the molecular density to block off water vapor. Although it may seem like it’s impermeable, what you aren’t seeing is the smallest of liquid molecules permeating through the plastic sheet. If you use a normal sheet of plastic as a vapor barrier, you will still experience a humid, wet basement. It is best to use a professional waterproofing company and have them provide you with a long-lasting solution.
The Effectiveness
You have to remember that, due to its location, your basement is constantly fighting off moisture. If you’re going to choose a material to prevent moisture from entering your basement, you’ll want to make sure that it’s one that can withstand years of moisture exposure. Polyethylene is one such material, as it’s among the most durable plastics in the world and can be subjected to water exposure for decades without ever breaking apart. Not only that, but it does not harbor any mold, making it the perfect material to use as a vapor barrier for basements.
The normal plastic we use in our day-to-day lives is also capable of harboring bacteria. This can encourage mold to grow on the plastic since it eats microorganisms. With all this in mind, it is impossible to compare a competent vapor barrier like WallSeal to a simple plastic sheet.