Waterproof concrete - what is it?
What is waterproof concrete?
Waterproof concrete, watertight readymix concrete or waterproofed concrete keeps water out of the concrete. Ordinary concrete contains fine pores which allow moisture to penetrate the surface and pass through. The size and volume of these pores is dictated by the water/cement ratio; the higher the ratio, the more porous the concrete.
Special concrete admixtures make the concrete watertight. One waterproofing admixture reduces the water/cement ratio, increasing the density of the mix and minimising the size of the pores. The second waterproofing admixture fills the remaining pores ensuring a completely watertight finish.
Benefits of using waterproof concrete
- No additional preparation or oil-based membrance required to make the concrete waterproof.
- This means less time and labour on site.
- Better for the environment
- Less susceptible to cracking
Find our more about Tarmac's waterproof concrete
Product and technical specification downloads
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