Quick answer
Add an integral waterproofer to the mix so the plaster, screed or concrete itself resists water. Sika-1 is a liquid: dilute 1 part Sika-1 in 10 parts water (about 3% of the cement content) and use that as the mixing water; with very wet sand use 1:8. Sikalite-101 is a powder dosed at 2% of the cement weight. Both reduce water absorption but don't replace a surface waterproofing membrane on roofs, tanks and wet areas.
Common causes
- Ordinary sand-cement plaster and screed absorb water through their pores
- External walls and roof screeds facing monsoon rain
- Basement walls and plinths in contact with damp soil
Step-by-step
- 1
Pick the product
Sika-1 (liquid, 5 L, 20 L and 200 L) for site mixing with gauging water; Sikalite-101 (1 kg powder) for small batches and screeds.
- 2
Dose correctly
Sika-1: 1 part to 10 parts water (about 3% of cement), 1:8 with very wet sand, 1:6 in extreme cases. Sikalite-101: 2% by weight of cement.
- 3
Mix
Use the diluted Sika-1 as all of the mixing water, or blend Sikalite-101 with the dry cement before adding water.
- 4
Apply and cure
Plaster or screed as normal in layers and cure properly — keep it damp for several days so it doesn't crack.
Always follow the current Sika Pakistan product datasheet for surface preparation, temperatures and curing.
Products for this job
Frequently asked questions
What is the price of Sika-1 in Pakistan?
Sika-1 PK is sold in 5 L, 20 L and 200 L packs; the live price for each is on the Sika-1 PK product page.
Sika-1 or Sikalite-101: which is better?
Both are integral waterproofers. Sika-1 is a liquid mixed into the gauging water and suits larger site work; Sikalite-101 is a powder at 2% of the cement weight, convenient for small batches. Choose by job size and how you mix.
How much Sika-1 per bag of cement?
Dilute Sika-1 at 1 part to 10 parts water and use it as the mixing water — about 3% of the cement content. With very wet sand use 1:8.