A Fimon stone is a lightweight, perforated or hollow building block used for partitions and lightweight façade construction. The block stands out for its low density and good thermal properties. Because of the hollow structure it is faster and cheaper to lay than a solid brick and loads floors less.
Properties
The Fimon stone has the following characteristics:
- Low weight — bulk density 400–900 kg/m³
- Hollow structure — air channels reduce material use
- Good insulation — λ value around 0.15–0.25 W/m·K
- Sound-damping — through mass and voids
- Fire-resistant — inorganic material, non-combustible
- Dimensionally stable — easy to lay in mortar or glue
Application
Fimon stones are widely used in:
Partitions
- Non-loadbearing partitions — between rooms
- Lightweight partitions in office buildings
- Inner cavity leaf — as backing wall
Façades
- Outer cavity leaf — for plastered façades
- Build-up over window heads
Special uses
- Wall build-up around services — easy to chase for pipes
- Acoustic separating walls between dwellings
- Fire separating walls — meeting fire resistance criteria
Workmanship
Fimon stones are traditionally laid with:
- Glue mortar — thin joints 2–3 mm, fast stacking
- Standard mortar — classic joints 10–12 mm
- Accessories — end blocks, corner blocks, lintels
For service penetrations the blocks can be easily chased or drilled. For heavy fixings (kitchen units, sanitary ware) special plugs or through-anchors are required due to the hollow structure.
Comparison with other lightweight blocks
- Aerated concrete (AAC) — similar but with finer structure
- Calcium silicate — heavier, higher compressive strength
- Gypsum block — interior only, faster to lay
- Pumice — volcanic lightweight concrete with similar properties
Related terms
- Aerated concrete
- Lightweight concrete
- Pumice
- Partition wall
- Calcium silicate
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