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Argex® Lightweight Floor & Roof Screed Basecoat
Product Code: 7840

 12 Pack Pallet:   £189.60 Inc VAT and delivery* 
 25 Pack Pallet:   £276.00 Inc VAT and delivery* 
 50 Pack Pallet:   £374.40 Inc VAT and delivery* 
 63 Pack Pallet:   £447.60 Inc VAT and delivery* 


Tested by LaboSport

Argex® 4-8mm No Fines Lightweight Floor and Roof Screed Basecoat. Product contains a minimum of "fines", and is offered for the onsite production of lightweight screed prior to topping off with standard sand / cement.

Prices shown for 12 Pack Pallet (Approx 0.24m3): 25 Pack Pallet (Approx 0.5m3) : 50 Pack Pallet (Approx 1m3) : 63 Pack Pallet (Approx 1.25m3)
For bulk loads please contact our sales office on 01889 580660 , email sales@specialistaggregates.com.

Pack Size: 16kg (Approx 20ltr)

Granule Size: Approx. 4-8mm.

Bulk Density: ARGEX® is a lightweight aggregate with a bulk density at point of supply of approximately 760 kg/m3. (ie volume for volume Argex ® is approximately half the weight of "normal" limestone or gravel aggregate).

Moisture Content: As supplied 4-8mm Argex ® is likely to contain a natural moisture content of approximately 15%.

Description & Application:
Argex® is a brick-like lightweight aggregate that is resistant to frost and chemicals, and will not break down in water. It is also non-combustible and has excellent sound and thermal insulation properties.

This selected grading of Argex® contains a minimum of "fines", (see typical grading below) and is offered for the onsite production of lightweight floor and roof screed basecoats.

Argex® lightweight screed basecoat is required to be topped off with a standard sand/cement topping.

Principal Advantages of Argex® Lightweight Screed

Concrete Screed Density Using the model design mix described below, screed densities of approximately 1.1 tonnes per m3 can be achieved. This represents approximately half the weight of traditional natural limestone / gravel based screed, providing significant weight savings and ease of manual placement.
Reduced Cost - Made with approximately half the cement of conventional sand screeds.
Quicker Drying Out - Free passage of air through the no fines structure ensures efficient drying.
Low Shrinkage A Argex® no fines basecoat exhibits low shrinkage ( 0.04%) therefore laying in bays is unnecessary.
Thermal Conductivity λ of Argex® Lightweight Screed is between 3 to 4 times lower than conventional sand screed
Falls - Ideal material for constructing falls as there is no maximum depth to which it can be laid.

Design Considerations: Applicable to both Argex® floor and roof screeds.

Strength / Mix Design
Clients should confirm mix design appropriate for their specific application.

A model design demonstrates that a 10:1 4-8mm Argex:Cement by volume may achieve a 6.0 N/mm2 compressive strength. ie 9 x 16kg packs of Argex requires 25kg of cement. A full 63 x 16kg pack pallet will require 7 x 25kg of cement.

When topped with the recommended 15mm of sand screed (4:1 Sand:Cement) this can withstand the point loading associated with office equipment etc.

Adequate water is required to hydrate the cement and provide workability, however, care needs to be taken not to wash the cement paste off the Argex aggregate.

Minimum Recommended Thickness - BaseCoat:
When bonded to a hardened base - 25mm
Unbonded & Floating Screed - 50mm. Subject to insulation suppliers recommendations
Over and adjacent to secured pipes and conduits - 50mm

Maximum Recommended Thickness - Basecoat:
Unlike conventional concrete screeds there is no maximum thickness to which Argex® No Fines Lightweight Screed Basecoat can be laid.

Minimum Recommended Thickness Sand Screed Topping: 15mm

Argex® no fines screed should be laid and tamped by hand - mechanical placement should not be used. The finished basecoat should be covered with sheeting to allow for the cement to cure and prevent drying out.

The cement topping should be laid once the basecoat has sufficiently hardened to support foot traffic . Self leveling screeds should not be used as these will flow into the voids of the no fines basecoat

Argex® (often generically known in the trade as Lytag) lightweight screed aggregate is manufactured from selected natural clays, which are pelletised before firing in a rotary kiln. As it is fired, moisture in the pellets expands to produce a microporous core while the pellet fuses to a brick-like form. The resulting granules are lightweight, porous, and have a high resistance to crushing.

Environmental Considerations:
As Argex®is approximately 50% the weight of "normal" aggregate, twice the volume can be carried, reducing vehicle movements both on and off highway.
For a given volume, bound Argex® concretes and screeds use less cement, therefore providing a significant energy saving.

Particle Size:
Sieve Size mm % Passing
10 100%
8.0 97%
6.3 46%
4.0 7.4%
3.15 2.5%
2.0 0.6%
Physical Properties:
Moisture Content as delivered BS EN 1097-5:1999 15%
Aggregate Crushing Strength (BS EN 13055) 12.89 Nmm2
Bulk Density 760kg/m3
Permeability BS1377:Pt5 1999
Chemical Composition:
Principal components typically:
Chloride 0.001%
Acid Soluble sulphate 0.157%



Specify: 4-8mm Argex Lightweight Screed Aggregate from Specialist Aggregates.

Bulk Loads Available
Contact our sales office for pricing
T: 01889 580 660
E: Sales@specialistaggregates.com
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Argex® Lightweight Floor & Roof Screed Basecoat
Argex® Lightweight Floor & Roof Screed Basecoat
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Argex® Lightweight Floor & Roof Screed Basecoat
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