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Is the snow ever going to end? Did you know that Volclay Voltex and Ultraseal can be applied in virtually any weather? It doesn't have any temperature restrictions and isn't adversly affected by rain, snow or extreme cold/hot temps. Also, contained Bentonite waterproofing membranes, such as Volclay Voltex and Ultraseal aren't affected by wet/dry cycling. This is a myth from the "old" bentonite waterproofing days of Volclay Panels and other unconfined Bentonite systems. Check out the technical resource documents below from CETCO explaining why Voltex isn't adversely affected by wet/dry cycling and exposure to rain or snow during application and prior to concrete being poured.

When I walk into a below grade parking garage I always look down. I'm curious to see what type of membrane is used and how it is holding up. I never used to look up. That is until Neogard came out with their Neocrylic LR (light reflective) coating for interior parking garage walls and ceilings. It is amazing to me how a light reflective coating can instantly brighten a garage and make it look clean and new. Next time you are in a parking garage take the time to look up and see what a difference a light reflective coating like Neocrylic LR could make. For more information click on Neocrylic LR.

I hope you enjoy reading this newsletter and find the information helpful. If you do and know someone who might be interested in receiving it, please feel free to
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As always, I am open to suggestions and comments so please feel free to email me at marla@dre.ca. I'd love to hear your feedback.

Best Regards,

Marla

Bentonite Membranes and Water Exposure...

BENTONITE WATERPROOFING AND WET/DRY CYCLING

Perhaps no other aspect of bentonite waterproofing is as misunderstood as how it responds to wet/dry cycling.

To address this issue, it is first necessary to understand the hydration properties of bentonite. First, sodium bentonite will exhibit a powerful suction force and can hydrate itself even if no water is added to it.

View/Download the Technical Document (PDF - 437KB)

ASSESSING THE CONDITION OF HYDRATED VOLTEX

It is often asked whether the "unconfined hydration" of Voltex (where the product is wetted before being covered with soil or concrete) requires the product to be removed and replaced with new materials.

In most cases, this is not necessary, and the Voltex will perform as intended regardless of its moisture content at the time of covering. The purpose of this document is describe the conditions attached to this general recommendation so that a case-by-case decision can be made on the serviceability of hydrated Voltex.

View/Download the Technical Document (PDF - 93KB)

When Earthtech Canada Inc. required epoxy coatings for the new Biosolids Complex at the Clarkson Wastewater Treatment Plant in Mississauga, Ontario, they chose Neogard CG 32, CG 125 and Wallgard 40.

The new Biosolids building houses thickening and dewatering equipment as well as provides for polymer, sludge loading and maintenance facilities.

Clarkson WTPEarthtech required coatings that had resistance to chemicals and were easy to maintain. Over 40,000 sq ft of Neogard epoxy coatings were used on the Biosolids Building in 2006.

Aggregate Loading in Nosing Materials of Parking Deck Expansion Joint Systems

Effects of Aggregate Loading:

Heavily Loaded: A sample of heavily loaded resin shows the abundance of aggregate. This makes the nosing material very dry, very hard, very brittle, and very likely to fail under snow-plow impact, deflection of the deck, and differential expansion in relation to the concrete and/or simply as a consequence of normal traffic over time.

When snow plows hit heavily-aggregate-loaded nosings they shatter and send the shock into the adjacent nosing resulting in widespread damage.

Conservatively Loaded: A sample of lightly loaded resin shows a good balance of aggregates and resin. The result is sufficient compressive strength to resist plow impact, and withstand traffic rigors, while not sacrificing flexibility.

When snow plows hit conservatively loaded nosing, it shaves locally, dissipates the shock, and leaves the joint functional and watertight.

For more information on aggregate loading click here.

Can you paint over Chem-Trete Protectosil Water Repellents?

There are several types of paints which can be applied over a substrate treated with a Degussa water repellent. The Degussa products most commonly applied to masonry and concrete are: Chem-Trete BSM 40 VOC, PB VOC, and Dynasylan BH-N.

In addition, water borne water repellents including Aqua-Trete and Aqua-Trete Emulsion EM are applied to clay and concrete masonry; while Aqua-Trete BSM 20 and BSM 40, also water borne, are applied to concrete.

All these products are based on silane chemistry. They impart water repellency to a substrate by bonding an organosilane to porous silica-type surfaces. This process changes the surface tension of the substrate so as to repel water.

A Better Paint when Applied Over Chem-Trete Products

The use of Chem-Trete, Aqua-Trete or Dynasylan products prior to the application of the paint provides additional benefits, besides a highly water repellent surface. The silanes used in the Chem-Trete formulations actually increase the adhesion of acrylic, epoxy and alkyds. The adhesion of these paints can be increased as much as 30% when applied over a substrate treated with a Chem-Trete product.

All the Degussa products, with the exception of BSM 40 D, Dynasylan BH-N Plus, and Aqua-Trete SG can be painted over with solvent or water borne acrylic, epoxy, or oil based paints. The Chem-Trete BSM 40D, because it contains special binders for calcareous substrates, may interfere with paint adhesion. If the base resin of paint is an acrylic, epoxy or oil, it will be compatible with a silane treated surface. The area in which incompatibility may be a problem is in the solvent or carrier of the paint.

The surface tension of the paint must be low enough to allow it to "wet out" and spread on the surface to be painted. If the paint can not be uniformly spread over the surface, the paint will have low adhesion or a poor appearance. Therefore, the carrier or carrier system employed by the paint is as important as the actual resin.

The typical solvents used in paint formulations, alcohol, mineral spirits, ketone, toluene and other such solvents will spread readily over a silane treated surface.

Water borne systems pose a different problem. Water borne paints employ emulsifiers, wetting agents and sometimes solvents to carry the paint resin in a stable suspension. Generally, most water borne paints are emulsions of the resin in water. Surfactants are used to emulsify the resin. Surfactants lower the surface tension at the water-resin interface to allow materials which are not soluble to form a uniform emulsion.

Because of the use of surfactants, some water borne paints have a low enough surface tension to evenly spread over a silane treated substrate. Generally, the acrylic based and latex rubber paints have a surfactant system which allows them to "wet out" over silane treated concrete and masonry.

Because of variations in paint formulations, substrate conditions and environmental aspects, it is recommended to apply a test section of the paint over the Chem-Trete, Aqua-Trete or Dynasylan treated surface, and check for compatibility.