Why we use river sand for waterproofing work Can we use crush sand or process sand or slag byproduct of iron industry

Why we use river sand for waterproofing work Can we use crush sand or process sand or slag byproduct of iron industry. Which one is better quality for waterproofing
 

Dnyan Deshmukh

Staff member
River sand was a first choice for doing waterproofing due to the fact that, it was available in ample amount, there was no restrictions on extraction of sand from river bed. Now in many states extraction of sand from river bed is banned and using River sand for any work is like damaging our environment by a great extent.

We should avoid the use of river sand as much as possible and should look into the possibility of using alternative materials like crush rock sand or M sand or anything which we feel can be used.

River sand was rounder in shape which has less surface area thus was giving a good bond with lessor cement content. Now a days even if you go for the river sand, there is a difference of what you were getting in past decade and now. Due to band on extraction, many parties tries to extract it from the locations which will give you high silts and harmful materials in it.

Before going for any alternative on full scale, we should do a trials and experiments on it. we should prepare a mixes which will give a better results.

If we talk from waterproofing point of view, it just a layer of mortar which is preventing leaking of water to the mother slab. leakage mostly occurs through cracks in waterproofing layer which passes to bottom of the slab and makes everyone uncomfortable.

We should also think on how to ensure mother slab is 100% water tight instead of simply relying on waterproofing layer / coating.

A good waterproofing is the one in which the mother slab is 100% watertight. You need to derive the processes to ensure this things happen just from the beginning when we place a concrete into the formwork. you need to look at compaction, finishing, curing in order to form a dense, well finished and crack free slab. Doing it right first time will save you from all kinds of failure in waterproofing system because the leaking water will never leak down from the mother slab, instead it will rise up in the sunk slab and come up above the floor tile if everything you done in waterproofing system fails to perform.

Doing rectification of such failure is easy and fast which reduce the dissatisfaction level in customer by great extent in cases where failures / defects do occurs.

there are many articles I have written about finishing of concrete, preventing cracking in concrete and how to do waterproofing, going through those will help you to derive a better waterproofing system.

Use of M Sand will give you very good results when compare with normal crush rock sand, Manufactured sand do contains very less amount of 150 micron passing particles and the shape of the particles are more towards cubical and round. using slag could be good option but not economical one, slag is almost coming in the bracket of cement price.