Del Carmen Slate
Where slate is put onto a roof it is expected to stay there , unchanging and maintenance free for many years.
Del Carmen slate is specially and exclusively quarried from the Del Carmen Quarry in North West Spain to offer customers a top of the range slate usually sought by demanding markets such as Germany or France.
The blue/black class "A" slate is totally natural, does not fade in sunlight, delaminate, crack or discolour. As it ages it does so beautifully. Extensive and regular testing to British, French, German and Belgium Standards coupled with centuries of experience prove that Del Carmen slates have their place among the very best roof slates available. Del Carmen is graded S1 as per the American ASTM standard which means a life expectancy of at least 75 years.
Many quarries in Spain produce slate that satisfies the conditions of BS 680, however only a small number can achieve the severe French standard P32/302 Class A.
Del Carmen slate is free from damaging pyrites and sulphates which can cause premature failure. The longitudinal grain, inertness to acids, polluted atmospheres and insect attack have made Del Carmen a sought after slate for replacement of roofs on heritage and historical buildings throughout the UK and Scotland.
With proper fixing and detailing Del Carmen slates are suitable for pitches as low as 17 degrees.
| TESTS |
DEL CARMEN | BS 680 PART2 1971 | FRENCH P32/302 CLASS A |
|
| WATER ABSORPTION | 0.30% | <0.30% | <0.40% | |
| DENSITY (g/cm³) | 2.81 | No requirement | >2.75 | |
| CALCIUM CARBONATE | 0.3% | No requirement | <3% | |
| THICKNESS (mm) | Graded 5 to 6mm | Graded | >2.6 | |
| RESISTANCE TO FLEXION | Dry | 73 mpa | No requirement | >70 mpa |
| Wet | 44 mpa | No requirement | >40 mpa | |
| FROST TEST/LOSS OF MASS | 0.2% | No requirement | <0.3% | |
| PYRITES |
LEACHING | None | No requirement | Not permitted |
| NON LEACHING | None | No requirement | Permitted if not through | |
| SULPHURIC ACID IMMERSION TEST | Pass | Required | Required | |
| WET AND DRY TEST | Pass | Required | Required | |
| GRAIN LONGITUDINAL | Longitudinal | Longitudinal | No requirement | |
