Cinder Block
Definition and meaning of Cinder Block in real estate.
A cinder block is a lightweight structural block made from concrete and coal cinders, which are the ash residue left after burning coal. It is similar to a standard concrete block but is lighter and has lower load-bearing strength.
In more detail
Historically, cinder blocks were widely used in residential foundations, retaining walls, and utility buildings. Today, the term is often used colloquially to refer to modern concrete masonry units, which are actually made from sand and gravel and are much stronger. Cinder blocks are more porous than concrete blocks, making them more susceptible to moisture absorption and water intrusion if not properly sealed.
Buyers looking at homes with older cinder block basements should look closely for bowing, cracking, or signs of efflorescence, which indicates water penetration. Proper drainage systems and waterproofing are critical for structures built with these blocks.
Key facts
| Category | Property Types & Construction |
|---|---|
| Primary Components | Portland cement, water, and coal cinders |
| Common Concern | Moisture absorption and cracking |
| Modern Equivalent | Concrete masonry unit (CMU) |
A property owner constructs a garden retaining wall using vintage cinder blocks, applying a waterproof sealant to prevent the soil moisture from degrading the blocks.
Frequently asked questions
What is the difference between a concrete block and a cinder block?
Concrete blocks are made from crushed stone and gravel, making them heavy and strong, while cinder blocks contain coal ash, making them lighter but less durable.
Do cinder block foundations require waterproofing?
Yes, because cinder blocks are porous, they require exterior waterproofing membranes and functional drain tile to prevent water from entering a basement.