An acidic product (pH approx. 2) for removing lime and carbonate efflorescence from paving, concrete and engineering brick. 2-6 m² per litre. Not for use on metal, render or painted coatings.
Surface
Block paving
The surface the manufacturer intends this preparation for.
D-2W is an acidic product for lime and carbonate efflorescence - the white bloom that comes out on paving, concrete and engineering brick as water evaporates.
Efflorescence is alkaline, so it comes off with an acid - that is the only sensible direction and the reason an alkaline cleaner does nothing here. Coverage 2-6 m² per litre, pH approx. 2.
The same prohibitions as D-2B: no contact with metal, galvanised or painted coatings, render or water-absorbent materials. Dilution 1:1 for heavy soiling, undiluted for extreme.
The usual reason a sealing job fails is not the product but the substrate. A sealer will not bond to a surface with grease, lime efflorescence or an old coating on it.
New paving has to season first. Manufacturers state that period on the data sheet - usually around 28 days from the date the block was made. The figure for each product is under "Technical data".
Before sealing the whole area, test on a patch hidden by a planter or in a corner of the patio. The same product can read differently on two batches of the same material, and on a surface with old coating left on it, it will not bond at all.
That depends on the finish given in the technical data. An invisible product leaves the colour alone, a wet-look version deepens it permanently, and a colour sealer gives it a new shade. Each product's finish is listed under "Technical data".
By how the water behaves. While it still beads on the surface, the treatment is working. Once water starts soaking in and dark patches return after rain, the protection has worn out. We do not quote a number of years, because it depends on traffic, sun and whether the drive is salted in winter.
No. Water occupies the pores the product is meant to enter, and stays trapped under the film. The result is often a milky bloom that cannot be removed without stripping the coat. The exceptions - products that allow slight surface dampness - say so in their technical data.
Use the calculator under the product description: it takes the manufacturer's coverage figure, the number of coats and the absorbency of the substrate, and turns them into pack sizes. On older, thirstier paving, work to the lower end of the coverage range.
Penetrating products form no film on the surface and do not change its grip. Where a manufacturer says something about slipperiness, we quote it in the technical data. If the surface is already slippery, the right product is an anti-slip treatment, not a sealer.
A 1:4 dilution means one part product to four parts water - a litre of concentrate gives five litres of working solution. Where the ratio is given in ml per litre of water (the C range), work the other way: 50 ml per litre means 20 litres of solution from one litre of concentrate.
It can, as long as water is drawing salts up from the sub-base. Removing efflorescence treats the symptom; limiting water uptake - that is, sealing after washing and drying - treats the cause.
We would advise against it. Hydrochloric acid dissolves the cement binder along with the efflorescence, washes out the joints and opens up the structure of the concrete, so the efflorescence returns sooner.
The technical sheet and safety data sheet will be available after approval.
Enter the area and how absorbent the substrate is. We work out the litres and the packs.
Depending on how heavily soiled the surface is and on its texture.
Example for 45 m²
11.3L
Enter your own area to calculate for your job.
Go directly to the right category. We do not imply compatibility across materials.