Concrete Repair Mortars

Weber.cem Lightweight

High-build, cementious mortar for vehicle and soffit repairs.

Weber.cem lightweight is a polymer-modified, cementitious mortar mix, with specially selected lightweight fillers. It is pre-blended, contains a polymer powder and simply requires the addition of clean water to produce a mortar suitable for both soffit and vertical repairs in situations where high-build replacement with conventional concrete is impractical. Since its introduction in 1985, weber.cem lightweight has been widely used in concrete repairs because of its ability to be applied on to vertical and soffit surfaces.


  • High-build concrete repairs
  • Repairs to soffits
  • Repairs to building structures

Features & Properties:

  • High-build up to 75 mm in soffit patch repairs, without formwork.
  • Easy to apply, excellent application properties.
  • Excellent adhesion to well prepared concrete.
  • Factory pre-blending eliminates onsite mixing errors and variations in quality, availability and grading of local cements and aggregates.
  • Can be overcoated with weber.cote anticarbonation coatings for optimum protection of reinforced concrete.

Technical Data:

20 kg weber.cem lightweight with 2.4 litres of water cured at 20°C.

  3 days 7 days 28 days
Compressive strength 
(BS6319: Pt 2: 1983) 
20 N/mm2 23 N/mm2 30 N/mm2
Tensile strength 
(BS6319: Pt 7: 1985)
- 1·6 N/mm2 2·5 N/mm2
Flexural strength 
(BS6319:Pt 3:1983) 
- 4·5 N/mm2 5·5 N/mm2

Plastic density (with 2·4 litres of water)
Working life: 30 to 40 minutes depending on temperature


Tests carried out by Queens University Belfast using CLAM test. Samples soaked for 24 hours prior to test (permeability coefficient only) weber.cem lightweight with:

  Permeability coefficient
Initial absorption
2·4 litres water per 20 kg     1·21 x 10–14 22·1 x 10–14
OPC concrete mix with 
w/c ratio 0·6    
48 x 10–14 211 x 10–14
OPC concrete mix with 
w/c ratio 0·4    
2· 3 x 10–14 19·6 x 10–14

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12 Fenlake Business Centre, Fengate, PE1 5BQ

01733 560362

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