Hemelite Medium Dense Block 100mm | 7.3N
£1.50 £1.80 incl. VAT
Hemelite Medium Dense | 7.3N
Hemelite Medium Solid Dense 7.3 N bridges the gap between lightweight aircrete and heavy dense blocks. Its reduced density improves thermal efficiency and sound insulation while easing manual handling, yet it still delivers a impressive 7.3 N/mm² compressive strength. Designed for use in load-bearing walls above and below the DPC as well as beam and block floor infill, it’s a versatile solution for both internal and external masonry.
Weighing around 14.1 kg per block, Hemelite Medium Solid Dense 7.3 N offers a handling advantage over traditional dense blocks while retaining its structural strength. Its thermal conductivity of approximately 0.51 W/m·K helps meet Part L energy targets when combined with a 150mm cavity and insulation, and its Class A1 non-combustible rating under BS EN 13501-1 provides up to 60 minutes of fire protection in wall constructions.
For external, bellow DPC blockwork 7.3N blocks or above are required.
Key Features & Benefits:
- Lightweight Yet Strong: Weighing less than traditional dense blocks, the Hemelite 7.3N is easier to handle and transport, yet maintains the same high strength and durability for reliable performance.
- Efficient and Safe: The reduced weight ensures quicker and safer laying, helping to save time, reduce labor costs, and minimise the risk of injury on-site.
- Versatile Applications: Suitable for both internal and external walls, this Hemelite block is ideal for use in load-bearing applications, beam and block floors, and various general construction projects.
- Fire Resistance: With excellent fire-resistant properties, this block offers added safety for structures, ensuring reliable protection in the event of a fire.
- Superior Acoustic Performance: Provides good sound insulation, contributing to quieter, more comfortable indoor environments.
- Customisation for Thermal Performance: Achieve your desired thermal performance with the addition of insulation, making it flexible for different project needs.
Technical Specifications:
- Dimensions (L×H×W): 440×215×100 mm
- Compressive Strength: 7.3 N/mm²
- Dry Density: 1450 kg/m³
- Thermal Conductivity: 0.51 W/m·K
- Fire Rating: Class A1 (non-combustible); 60 min fire resistance in wall constructions
- Sound Insulation: 44 dB reduction in partition walls (meets Part E)
- Unit Weight: 14.1 kg per block
- Blocks per Pack: 72 blocks (7.2 m² coverage)
- Mortar Joint: 10 mm recommended (BS 8000-3 compliant)
- Standards & Marking: BS EN 771-1 manufactured; UKCA marked
- Moisture Management: Requires external render or cladding; not for fair-faced exposure
| Weight | 14.1 kg |
|---|---|
| Height | 215mm |
| Length | 440mm |
| Depth | 100mm |
| Compressive Strength | 7.3N |
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Which mortar mix is best for these blocks?
For above ground a Class M4 masonry mortar (per BS EN 998-2) is recommended, providing at least 4 N/mm² compressive strength for durable, long-lasting joints.
For below ground, coastal areas or bad soil conditions a stronger mix may be required.
What’s the most efficient way to cut these blocks on site?
For fast, straight cuts use a manual block splitter; for precision work, a circular saw with a diamond-tipped blade; or for occasional or rough cuts, score and split with a hammer and bolster.
Do Hemelite walls need separate boarding before plastering or drylining?
No, Hemelite blocks provide an ideal background key for plaster, render or direct adhesion of plasterboard without additional boarding.
What suction characteristics do these blocks have for rendering?
Hemelite exhibits moderate suction, giving a reliable mechanical key for renders without excessive moisture draw-off that can cause cracking.
What fixings work best for mounting shelving or brackets into Hemelite blocks?
Hemelite provides a strong substrate for standard nylon or fibre wall plugs with light-duty screws. For heavier loads, mechanical or chemical anchors such as those in the fischer SX/FU series, have been test-proven to achieve reliable load bearing performance in Hemelite.
Tarmac manufacture concrete and aircrete block products used widely across UK masonry construction. The Tarmac products we supply include Toplite and Hemelite ranges, both of which are commonly specified for general walling and blockwork applications.
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