What Is Basement Waterproofing Mix?

Mix

• Waterproof compounds generally come in two types: premixed and those you mix on site. Mixes consist of specially formulated powders to which you add water to form a compound with the consistency of a thick paint. You generally add the powder to the water, rather than the water to the powder, for best results. Use an electric drill to mix the powder and the water to the appropriate thickness. If the mix becomes too thick, add more water and stir with the drill. For a mix with a thin consistency, add more powder.

Application

• You can add the mix directly to your basement walls if no large cracks are present. Fill small cracks less than 1/8 of an inch with the waterproof compound. Then apply the mix over the wall. Moistening the wall with a mist spray from a garden hose prepares it to accept the mix. Never apply a waterproof mix to a painted wall. Use the mix only in areas with a seepage problem. A second coat, applied 24 hours after the first coat, creates a stronger moisture barrier.

Cracks

• Large cracks in the wall need repair before you add the waterproofing compound. You must fill any large cracks with a regular mortar and then apply the waterproof mix once the mortar has set. If a strong outside pressure is causing the cracks, such as subsurface water, then applying mortar and waterproof mix may not solve the problem. You might need to call in a professional for advice in this case.

Tips

• You need to use proper technique when applying the mix to get the most out of the product. Laying on the mix with a stiff brush using a circular motion works best, according to the Ace Hardware website. When the coating dries, soak it with water and let it dry out again. Then soak it again the next day and spread on the second coat while the wall is still wet.