Concrete blocks
Sheet under review by our engineersAgglos, or concrete blocks, are the hollow concrete blocks used to build the walls of your house. They are laid one on top of the other with mortar (a mix of cement, sand, and water) to form the walls of your dwelling.
Why it matters for your home
The quality of concrete blocks (agglos/parpaings) and their proper installation are essential for insulation (thermal and sound), your walls' resistance to impact, and their ability to support the weight of upper elements. Poor quality blocks will crack or crumble, making your walls fragile.
The African context
Unfortunately, block quality varies enormously. Some have an incorrect cement mix, making them brittle. We often see walls built without respecting alignment, without vertical joints, or with overly lean mortar, promoting cracks.
Red flags
- ⚠ The blocks break easily during handling or when dropped from a small height.
- ⚠ Walls are built crooked, misaligned, or out of plumb.
- ⚠ The contractor uses very light-colored or very sandy mortar.
- ⚠ There are no vertical joints, or they are poorly filled.
Questions to ask
- 1. "Where do the blocks come from, and how do you guarantee their quality?"
- 2. "How will you check the plumb and alignment of the walls as work progresses?"
- 3. "What is the mortar mix for laying the walls?"
Cost hint (indicative)
One block costs between 250 and 500 FCFA per unit, excluding installation. Installation can add 1,500 to 3,000 FCFA/m² of wall.
Related terms
At this stage of your project?
An independent DiasporaBuild inspector can verify on site before you pay.