Basics about ‘Quality of Cement’ as you buy your dream home in India!
As a home buyer, knowing about the basic ingredients like Cement is a good idea before you buy your dream home in India. You may be buying an apartment or getting your independent home constructed with the help of a civil engineer/architect. Knowing about the basics always helps in making the right choice, and asking the right questions.
Cement is used to make ‘concrete’ and ‘mortar’, that in turn go into making our homes, and all the built environment around the globe.
Cement being good in quality helps prevent cracks and failures in our building. It allows the residential project to be safe, strong, and durable.
Is ‘Concrete’ the same as cement?
- No, the terms are not the same. Cement, concrete, and mortar are not to be used interchangeably.
- ‘Concrete’ is formed by mixing sand, gravel, or crushed stone with a ‘paste’ made with water and cement.
- ‘Mortar’ is a mixture of cement and fine aggregates used for bonding bricks.
- Cement is usually not used standalone. Cement is a ‘binder’ that sets and hardens. When cement is mixed with aggregates, it results in ‘concrete’ or ‘mortar’. So, cement is used to adhere and bind other materials together.
What is Portland cement?
[Source- https://www.greenspec.co.uk/ ]
- Based on calcium silicate (CaSiO3)
- Portland cement is made by combining calcium, silicon, aluminum, and iron oxide
- Portland cement is hydraulic cement. It ‘sets’ and ‘bonds’ due to a chemical reaction between ‘water’ and ‘dry cement’
- Portland cement is the most common cement for concrete applications today
- Other cement types: calcium aluminate, carbon bond, phosphate, slag, polymer bond, epoxy, and several others.
Determining the quality of cement
- How do a professional builder and civil engineer determine the ‘quality of cement’? As a home buyer, how can you need to know the basics so that you can not only see the construction yourself but also understand what’s happening?
- By knowing the basics, you are better equipped to observe and draw meaningful understanding when you make an on-site visit to your dream home under construction.
A. Cement Grade
- Ordinary Portland cement (OPC) comes in different ‘grades’ for different purposes
- 33 Grade OPC: For general construction in normal environmental conditions
- 43 Grade OPC: For brickwork, foundations, plastering, and compound wall applications
- 53 Grade OPC: For high strength and durability for structures such as tall buildings, bridges, and heavy-duty buildings
- Standards set for OPC grades are depicted below
- Your builder needs to use the cement-based on the grades, and have a reputable brand and source of cement. Machine-stitched branded bags secure the quality of the grade. Watch for those at the construction site.
B. Post-Purchase Inspection
Your builder would need to undertake checks on the ‘quality of cement’ on-site to make sure it is good!
- The cement should be in a bag
- The stitching of the bag must be intact with no holes
- Look for ISI or CE certification marks/symbols on the bag
- The date of manufacture must be printed on the cement bag
- The strength of cement degrades, so the fresher the bag, the better
- It should not be more than 90 days old. After three months, cement strength goes down by 20-30 percent. In 6 months, strength reduces further to 30-40 percent, and after 12 months, the strength of cement goes down to 50 percent
- You can feel the strength of cement by just feeling and looking at the cement in your hands. Lump-free and dust-free cement that feels cool upon touching are good! It means that it is not hydrated, because hydration is bad (which means its absorbs water). The Colour of the cement should be uniform, and greenish-gray
Water Test on cement
- When you pour a bucket of water, good-quality cement shows that it has no impurities. It will simply float on the surface for a few seconds before it sinks into the water
- If cement gives you an earthy smell, it means that it is not good, since it contains excessive clay and silt
These are some basics, while the list can be far more exhaustive. But, knowing about this matters for a home buyer for asking the right questions to your builder! Being better equipped to question the builder helps you make the right choice for a high-quality, well-built dream home!
“Quality is never an accident; it is always the result of high intention, sincere effort, intelligent direction and skillful execution; it represents the wise choice of many alternatives.”– William A. Foster
To know more about “What Is Cement? And Understanding The Importance Of Cement For Your Dream Home In India!”.Click here!