BRE Report

What is the BRE Report?

It is a data sheet which is compiled by the Building Research Establishment or “BRE”. The Report or “data sheet” was compiled in May 2000. The work was carried out by BRE as part of a Partners in Technology Programme funded by A & D Sutherland Ltd. and The DOE, Transport and the Regions and does not represent an endorsement of the stone by BRE.

Nominal Slab Thickness: Typical use:-

25mm Pedestrian areas only.
30mm Pedestrian and cycle areas, gardens, balconies.
35mm Occasional car, light vehicles and motorcycle access. Garage entrances.
40mm Walking places, market places occasionally used by delivery vehicles and emergency vehicles.
50mm Pedestrian areas often used by heavy lorries.
65mm Roads and streets, petrol stations.

Test Results – Caithness Flagstone

Test Methods – Note 1 = EN1341, Note 2 = EN1341/BRE 141

Safety in Use

Slip Resistance (Note 1) 62 Wet. Values > 40 are considered safe.

Strength Under Load

Compressive Strength Parallel to Grain 128N/mm2
Compressive Strength Perpendicular to Grain 150N/mm2
Mean Flexural Strength (Dry Perpendicular Note 1) 37.2 MPa

Porosity and Water Absorption

Porosity (Note 2) 0.3%
Saturation Coefficient (Note 2) 0.98
Water Absorption 0.1% (by wt)
Density 2684kg/M3

Resistance to Frost

Flexural strength after Freeze/Thaw Test (Note 2) 39.2 MPa Loaded perpendicular to the bedding plane, ambient temperature.

Resistance to Salt

Sodium Sulphate Crystallisation Test (Note 2) 0.05% Mean wt loss
Sodium Sulphate Crystallisation Test (Saturated) (Note 2) 0.0% Mean wt loss.

Petrography

Caithness Flagstone is from the old red sandstone of the Devonian age. It is very fine grained with a dark grey colour which may weather to a fawn or ochre.