HOMOGENEOUS (monolithic) and HETEROGENEOUS system of Flooring / coatings – advantages and disadvantageous by built up system

There are many more type of floorings and coatings materials are available in market.. Say Cementitious, epoxy, Polyurethane, etc. Depending on the performance requirement, client or end user choose them. However, when cost comes in to the context, applicator as well as the client try to compromise on what it initially thought of having… May it be look, bond strength, abrasion resistant, temperature resistant, chemical resistant, etc.,

Let see H O W….. 
In general topping product will come with high cost than the below the underlay screed or primer. Many manufacturer’s or the applicator propose to use the primer + quartz / silica (the inert sand like particles) to build-up the thickness. Even some will propose to use the underlayment to build up the thickness. Like this, they bring down the overall cost of the system.

It is universally agreeable that the use of primer is necessary for suppressing the dust, getting the more coverage of the topping material, seal the porosity of the surface, etc. In addition, screed material is really need to fill up the undulations of the floor. However, it cannot be agreeable just compromise in the cost.

System of flooring be of homogeneous or may be of heterogeneous. Homogeneous is the one, from bottom to top, of the same product or by the product of the same family of chemistry. And, the heterogeneous means, the combination of many product from different family of chemistry.

Let see the advantages and disadvantageous of system built up of HOMOGENEOUS and HETEROGENEOUS system.

LOOK: Of course, the final look of the installed material will be same at initial stage. However, if, the underneath built up with low cost product and the topping of very thin product layer, then how much time it may remain the same? Due to wear, the topping will end-up exposing what is at bottom. Colour variation, undulations, etc. will be the resultant. In this case, if homogeneous system is used will preserve it’s LOOK, no matter how much it wear off.
Aggregate used in between the 2 coats of prime / on the primer coat, top coat shall be applied with care using spike rolling, if not pinholes will emerge on the topping.

BOND STRENGTH: Bond between the products of different chemistry family will always a doubtful. So the manufacturer’s and the applicator propose to use inert material which does not play any role chemically but physical they sit on the wet surface on the applied product and provides the mechanically key for the subsequent applied product. In case of proposing the screed product, manufacturer shall propose the bonding guarantee not the applicator. Hence, it can take as granted that the homogeneous system built up will have the good bonding on the substrate and stays in position for long time.

ABRASION RESISTANT: No need to explain again as it was explained in the LOOK aspects, HETEROGENEOUS system would have different abrasion resistant property. Inert sand like particles, will lost the position and system will fail very badly.

TEMPERATURE RESISTANT: Any material to resistant the temperature it should have unique or at least similar coefficient of thermal expansion. This will not be guaranteed in the HETEROGENEOUS system, but it can take as granted that the HOMOGENEOUS system built up will have same coefficient of thermal expansion. For more details, refer https://annayyachandrashekar.blogspot.com/2018/01/relative-linear-shrinkage-and.html

CHEMICAL RESISTANT: No need to explain it again, as the system built up in HETEROGENEOUS system is from the different kind of products, the chemical resistant will vary with it matrix. But, this property will remain same from top to bottom in HOMOGENEOUS system built up system because of using the same kind of product over all. Make sure to get the chemical resistant chart from the manufacture not from the applicator. Even then, it is necessary to get the sample done on your premises so that you can be get tested at site level too.

Then, say always NO TO HETEROGENEOUS system? 

No. this also stays good, if the flooring or coating is intended for short term only. Say, a renovation for short term, to get pass the auditing process, un-avoidable / terrible site condition where usage of the floor itself is heavy. 

Finally, HETEROGENEOUS system can be used for short term run and HOMOGENEOUS system can be used for short time as well as long time run.