Everbuild Opti-mix Integral Waterproofer 1 Litre

Everbuild Opti-mix Integral Waterproofer is a highly concentrated admixture for sand and cement mixes that reduces water permeability in mortar, concrete, render, and screeds. As an integral waterproofer, it works from within the mix rather than coating the surface, giving long-term protection against water ingress wherever the material is placed. One litre of Opti-mix is equivalent to ten litres of conventional waterproofer, so it goes a long way even on larger jobs.

The formula also includes plasticising and air-entraining agents, which means there is no need to add a separate plasticiser to the gauging water. The mix stays workable and easy to handle without becoming weak or over-wet. Bleeding is reduced, and the finished material holds up better through freeze-thaw cycles, which matters on external work in colder months.

The measuring cup is built into the bottle, so dosing is straightforward. Squeeze the sides to fill the cup to the required level, between 25ml and 45ml per 25kg of cement. There is no guesswork and no separate measuring equipment needed on site.

Where Everbuild Opti-mix Integral Waterproofer Gets Used

This product is well suited to any application where water resistance in the mix itself is the priority. External rendering and pointing benefit directly, as the mortar absorbs far less moisture once cured. Below-ground structures such as retaining walls, inspection chambers, and cellar walls are common applications, where the ground is permanently damp and ordinary mortar would deteriorate over time.

Pool and tank linings are another typical use, provided the Opti-mix is combined with an appropriate DPM membrane for full tanking systems. Roof areas and parapet details where cement mixes are used also benefit from the added water resistance, particularly in exposed positions that take direct rainfall year-round.

Using Opti-mix as Part of a Tanking System

For tanking applications, Everbuild recommend using Opti-mix alongside their 908 DPM product rather than relying on the admixture alone. The integral waterproofer improves the mix itself, but it will not hold back permanent hydrostatic pressure on its own. Used together, the two products provide a more complete barrier for basement and below-ground waterproofing.

The integral waterproofer does not produce a water-repellent surface finish. Once the render or mortar has cured, water will not bead off the face the way it would with a surface sealer. If surface water repellency is needed alongside internal waterproofing, Everbuild 402 Waterseal applied over the cured render is the appropriate follow-up. Two different jobs, two different products.

Opti-mix Integral Waterproofer is available in boxes of twelve, making it a practical stock item for groundworkers, renderers, and general builders who regularly add admixtures to their mixes. At this concentration level, a single litre handles a significant volume of work before you need to reach for another bottle.