One of the most frustrating scenes to walk into is a leaking chimney. It is one of the applications that you don’t give much thought to until it is too late. Because bricks, stone, masonry are extremely porous they are at high risk of leakage if left unsealed. In order to prevent water leakage, mold, mildew and efflorescence from occurring to your chimney these are the steps to take:
- Clean the chimney, make sure all mold, mildew and efflorescence are completely removed.
- Fix any cracks in the mortar, or if the chimney is severely damaged re-point the chimney.
- Use a waterproofing sealer, like this one found at homedepot.com which is a silane/siloxane blend that will waterproof and protect your chimney from future leaks and water damage for over 10 years.
Basement waterproofing sealers are commonly used to seal pores and capillary tracts of concrete to prevent water from entering. A basement waterproofing sealer is needed anytime a basement is built at ground level or below ground level where ground water can build up in the soil, raise the water table and thus travel through the concrete. The higher the water table the more at risk the basement will be to hydrostatic pressure exerting itself to basement floors and walls. Hydrostatic pressure causes water to travel through cracks, joint openings and pores. Hydrostatic pressure can also cause mold, mildew and other moisture related problems in basements. By using a basement waterproofing sealer that can resist hydrostatic pressure the moisture and water are unable to cause damage to the concrete foundation.
Most Popular Basement Waterproofing Sealers:
Behr Basement & Masonry Waterproofer: This product works great and looks great at first until the first sign of heavy rain. When the product comes into contact with moisture it starts to peel up since it is not a breathable sealer. Thinner consistency than paint but if moisture is present or if the basement is exposed to a high water table the product fails. Readily available at The Home Depot.
Ghostshield 9500: This product is not a waterproofing paint but an invisible sealer that will not peel or delaminate if water is present. Through densification and hydrophobicity the product is able to put an end to water and moisture migration through a cementitious substrate. It is also an economical option since it is concentrated and makes 5 gallons. Readily available at The Home Depot.
UGL DryLok: Product claims to resist 10lbs of hydrostatic pressure with a 10 year warranty. Since this product is latex based is is worse than the Behr product at peeling up when it comes into contact with moisture. It is not breathable and states that it does not help to resist or reduce efflorscence. Readily available at The Home Depot.
Salt damage is most commonly due to exposure to de-icing salts. However, any chemical containing chlorides, including sodium chloride, potassium chloride, calcium chloride etc. found in “safe de-icing chemicals,” fertilizers, ocean water, etc. present a danger to the concrete. All are mildly acidic, and attack the bonds that hold concrete together.
In order to prevent de-icing and chloride damage it is best to use a silane sealer or a blended water based silane/siloxane sealer. If you are looking for the much desired water bead effect choose a silane/siloxane blend.
Enviroseal 40 – The Enviroseal 40 is an excellent source of protection for chlorides, freeze/thaw cycles, and other such potential threats. Because of this and other characteristics of its chemical formula, the Enviroseal 40 is a preferred sealer for certain environments that need protection from high traffic. The Enviroseal 40 is also a great choice because of its international appeal. As it is manufactured by BASF, you can be assured that it will perform up to the high standard required of that company.
Siloxa-Tek 8500 – The water based Siloxa-Tek 8500 is also an excellent choice because of the change to the surface tension to produce a water repellent surface keeping water and aggressive water-soluble salts, such as chlorides and sulfates, out. Siloxa-Tek 8500 can block up to 99% of surface moisture. The active ingredients seal the pores within the substrate adequately blocking surface moisture while still maintaining the concrete’s ability to breathe with an extremely visible water bead effect.
Prosoco Salt Guard WB – Saltguard WB is a ready-to-use water-based, VOC compliant silane/siloxane water repellent and “chloride screen” for the protection of concrete and masonry. This low odor and alkaline stable, Saltguard WB is ideal for field or in-plant application to concrete and most masonry. Saltguard WB protects horizontal and vertical surfaces from moisture intrusion and chemical attack of chloride salts.
All look alike products do not perform the same even though they are making similar claims. How do you know which one to believe?
Sodium Silicates: How do you know which one to believe definitely applies to sodium silicates. Sodium silicate formulas have been around since the 1950’s and were initially used as concrete floor hardeners. Today because of their economical nature many concrete manufacturers and distributors claim sodium silicates to be effective waterproofers. Sodium silicate solutions have a place as a concrete treatment; however, their role should only be limited as concrete surface hardeners. Sodium silicate solutions perform very poorly and ineffective as waterproofing sealers since they have a limited depth of penetration and they are unable to stop or reduce hydrostatic pressure. If you want to densify your concrete a sodium silicate hardener is an excellent option; however, leave the waterproofing to one of the other methods below.
Siliconates: Siliconates are as a highly alkaline aqueous solutions that are used for water-repellent impregnation. After the water has evaporated from the sealer, siliconate reacts with atmospheric carbon dioxide to form a water-repellent surface barrier. Siliconates are good water repellent options with an excellent water bead effect.
Silicate/Siliconates: An effective waterproofing method because of the densification properties of the silicate and the hydrophobic properties of the siliconate. Typically silicates are used to harden and siliconates are used to protect from water and by combining the two a dual action product is created. The silicate component reacts with the concrete by introducing additional silicate that reacts with excess calcium hydroxide to form more CSH. This results in a denser, harder concrete surface. The siliconate applied to the concrete undergoes a two part process in which it first reacts with carbon dioxide in the air to form an active silicone resin. The silicone resin then reacts with calcium hydroxide to form a liquid repellent resin on the concrete surface and within the available capillary pores. Siliconates are sealers, not densifiers and are best used when blended with silicate to provide both densifying and sealing properties. The seal elicited is microscopic and there is no film build up on the surface which means it cannot wear off over time. An excellent option for waterproofing basements and driveways.
Silanes: The main deterioration mechanism for concrete is corrosion and scaling due to deicing products. The most effective solution to protect water and salts from damaging concrete is to use a silane based sealer. Because silanes do not change the skid or slip resistance of concrete they are ideal for driving surfaces (aka driveways, bridges, roadways). Silanes penetrate deep because of their extremely small molecular size and they chemically bond with silica to form a permanent attachment of the water repellent molecule. This creates a deep hydrophobic layer that prevents water and waterborne contaminants from entering the substrate and causing premature deterioration. Silanes leave the surface with a completely invisible finish and elicit a water sheeting effect.
Siloxanes: Siloxanes have a larger size polymer and penetration is not as deep as other sealers. Unlike silanes, which require a high pH to catalyze, siloxanes are not dependent on substrate pH. Because of this, siloxanes are ideal for treating brick, stucco, and stone. Siloxanes are not commonly used as a stand alone products but to maximize their potential they are typically blended with silanes. Used as a stand alone product siloxanes may slightly darken the treated surface while also creating a water beading effect.
Silane/Siloxanes: Silanes and siloxanes are both derived from the silicone family. Despite being very closely related, they have significant performance differences. Because silanes are made up of smaller molecules than siloxanes, they typically will obtain deeper penetration than siloxanes. As a result, silanes perform well under abrasion and weathering conditions. A consequence, however, of this small molecular size is that silanes are relatively volatile. Therefore, the solids content of a silane product should be high enough to compensate for the loss of reactive material through evaporation during application and cure. Siloxanes, because they are less volatile, generally offer good water repellent performance at lower costs. However, for concrete surfaces subjected to abrasive wear, treatment with a silane sealer will provide longer lasting protection. In regard to surface texture and color, treatment with silane sealers typically cannot be detected visually. Siloxane products may slightly darken the treated surface. By using a combination of silanes and siloxanes the benefits of each compensate for the weaknesses of each making for the perfect DIY water repellent sealer. Silane/Siloxane blends are commonly used on driveways, sidewalks and leave the surface with a natural finish.
Elastomeric Coatings: Elastomeric coatings are rubberized emulsions which cure to provide a heavy duty rubber-like membrane for use in waterproofing or damp proofing concrete or masonry surfaces above and below grade. The term elastomeric simply means that the material is flexible. Elastomeric coatings are durable and essentially derivatives of urethanes and polyurethanes formulated into a liquid which can be applied to form a monolithic waterproofing membrane. While elastomeric coatings are impermeable to water, chemical vapors and sub-terrain gases they are at high risk of delamination with a short lifespan. They also alter and change the color, texture and surface appearance of concrete.
Crystalline Waterproofers: Crystalline waterproofing is an effective waterproofing method because it fills capillaries to prevent the penetration of water and other liquids from any direction. By way of diffusion, the reactive chemicals in crystalline waterproofers use water as a migrating medium to enter and travel down the capillaries of the concrete. A chemical reaction between the crystalline waterproofers occurs between moisture and the by-products of cement hydration, forming a new non-soluble crystalline structure. This integral structure fills the capillary tracts rendering the concrete waterproof.
There are a few different options when it comes to coloring concrete:
1. Integral coloring
Integral color is used when new concrete is being poured to add color to the concrete during the mixing process. The color is either in liquid or powder form and allows color to be added to the entire depth of the slab. This allows for a uniform color for a large amount of square footage.
2. Shake on color
Shake on color is used on new concrete by broadcasting small pigments of powder that work their way into the concrete. Water from the newly poured concrete wets the powder and causes the the color to bond with the top layer of concrete.
3. Acid Stains
Acid stains are chemically reactive and react with minerals in the concrete to create a unique, durable color effect. Acid stains are hazardous and must be neutralized after application. Acid stains can be used on new or old concrete slabs.
4. Acetone dyes
Acetone stains and dyes are solvent based and hazardous but can create vivid beautiful colors. They are not UV stable so a protective sealer should be used on top of an acetone dye to lock in the color.
5. Water-based dyes
Water based dyes are safe and easy to apply with all of the colors able to be mixed together to create patterns and effects. Since they are not UV stable a protective sealer should be used on top of water based dyes to lock in the color.
6. Color densifiers
Color densifiers are a new technology in which a colored, water based, lithium silicate solution is used. They allow you to densify the concrete while coloring it in the same step. The color densifiers are UV stable but a protective sealer can be used on top of a color densifier to lock in the color and add an additional sheen.