Frequently Asked Questions

Is Conplast WP sufficient on its own to provide the waterproofing for a below-ground basement, or should it be combined with a surface waterproof membrane?

Conplast WP integral waterproofing admixture improves the water resistance of concrete, but whether it is sufficient on its own for a specific below-ground basement application depends on the hydrostatic head (depth of water table above the base of the basement), the concrete mix quality, and the required waterproofing grade. Conplast WP reduces water absorption and capillary suction in the concrete matrix — it is most effective at reducing damp penetration from non-pressurised soil moisture and from low-head groundwater. For basements in Delhi NCR where the seasonal water table rise during monsoon creates a genuine hydrostatic head (water pressure) of 1 metre or more above the basement floor, Conplast WP alone without any surface waterproofing membrane is generally not sufficient for Grade 2 or Grade 3 waterproofing to BS 8102 requirements. In these conditions, the recommended approach is to use Conplast WP in the concrete mix (to produce a low-permeability concrete that minimises the water reaching the surface) combined with a surface-applied waterproof coating or membrane on the ground-side face (Nitoproof 300 for protection plus waterproofing, Brushbond TG or Nitoproof 600 for higher performance, or a sheet membrane for the highest reliability). This combined integral-plus-surface approach provides defence in depth that is much more reliable than either component alone.

How is Conplast WP compatible with superplasticisers from the Conplast range and can they be combined in the same mix design?

Conplast WP can generally be combined with Conplast superplasticisers (Conplast SP430 range, Auracast PCE range) in the same concrete mix design to achieve both high workability or water reduction (from the superplasticiser) and improved water resistance (from the WP admixture). However, compatibility between admixtures in a specific concrete mix with a specific cement type must be confirmed by trial mix before production batching — some combinations of admixtures with certain cement formulations (particularly cements with variable C3A content or with specific chemical composition) can produce unexpected interactions such as flash setting, excessive retardation, or loss of workability. The standard procedure for using Conplast WP alongside a superplasticiser is: add the superplasticiser to the gauging water first; then add the Conplast WP to the gauging water; add the combined admixture water to the aggregates and cement in the mixer in the normal sequence. Never add the two admixtures together undiluted (in concentrated form) before mixing them into the concrete — contact between concentrated admixture chemicals can cause chemical reactions that produce gelatinous or insoluble deposits. A trial mix confirming the fresh concrete properties (slump, air content, setting time) and hardened properties (28-day strength, water absorption) is the correct verification step before production.

What is the difference between Conplast WP and Proofex Integral for integral waterproofing and when should each be used?

Conplast WP and Proofex Integral both provide integral waterproofing of concrete added at the mixing stage, but they achieve this by different mechanisms and provide different performance levels. Conplast WP is a hydrophobic waterproofing admixture — it lines the capillary pores with water-repelling compounds that reduce water absorption by capillary suction, providing good protection against damp penetration from soil moisture and low hydrostatic head water. It is an economical and practical first-line waterproofing measure for general waterproof concrete applications. Proofex Integral is a crystalline waterproofing admixture that provides a different and higher level of waterproofing performance — it produces insoluble crystalline compounds that physically fill the capillary pores throughout the full concrete section, providing better resistance to higher hydrostatic heads, a self-sealing capability for fine cracks that develop after casting, and long-term maintained waterproofing as the crystalline formation is permanent and reactivates with water contact. Proofex Integral is specified for the most demanding below-ground waterproofing applications — deep basements with high permanent water table, water treatment and containment structures with high chemical exposure, tunnels and underground infrastructure with permanent hydrostatic pressure — where the hydrophobic mechanism of Conplast WP is not sufficient. For standard residential and commercial basements and water tanks in normal ground conditions, Conplast WP is adequate and economical. For the most critical waterproofing applications, Proofex Integral provides superior long-term performance.