Media

Laying a strong foundation

Construction World – April 2007

Your site has been excavated and the foundation footings placed. You’re ready to begin the formwork and pour the concrete. Or are you? The excavation has left little room to strip the forms, much less apply a water or damp-proofing membrane after surface preparation. The excavator is long gone and adjacent buildings leave you with little room to operate in any case. What can you do with no time and limited options?

Whether your foundation needs to be damp-proof or all out waterproofed against hydrostatic pressure, Integral Crystalline Waterproofing (ICW) provides a quick and cost-saving alternative to traditional membranes.

Challenged for space and time?
At any time before, during or after the construction of a below-grade concrete foundation, ICW can solve the problem quickly and easily. Simply add a crystalline waterproofing admixture at the batch plant or on site. Already poured? Crystalline surface treatments can be applied on the inside to solve your waterproofing challenge.

External waterproofing membranes require room to make the application on the outside of a structure. This can cause problems if you build too close to the property line or run out of room because of adjacent structures. Replace external membranes with a crystalline water-proofing admixture and you have the flexibility to design a larger footprint – maximizing space and getting the most out of your property.

Crystalline technology allows you to expedite construction schedules by backfilling sooner. In addition, the best manufacturer’s crystalline products are impervious to surface abrasion, wear and tear so there is no risk of tearing and puncturing a membrane system when it comes time to backfill.

Lower the cost of labour and materials
By eliminating external membranes you also save on the cost of labour and materials that would normally be involved with such a system. The best crystalline products become part of the concrete matrix. Unlike traditional external membranes, true crystalline waterproofing systems are permanent and do not require replacement. In addition, the leading systems have the unique ability to self-seal hairline cracks that inevitably occur over the life of a structure, thus saving time, money and aggravation years later.

How do I know which brand is best?
Once you have decided to go with crystalline waterproofing, you are faced with a choice of products from competing manufacturers. Choosing the best one can be problematic. One must be careful not to confuse crystalline waterproofing products with products that are simply concrete densifiers or pore blockers.

Watch also for products that claim to grow crystals but really only crystalline as they dry.

Such products do not grow through the concrete, nor do they reactivate in the presence of water to fill cracks. Products that contain silicates, stearates, or talc are temporary waterproofers at best, so manufacturers should offer long-term warranties and they should be able to state that their products are not
based on these chemicals.