Surfacing of blocks
With Prompt natural cement, perform type or monitoring trials at the same speed as sulphur surfacing, with breakage possible within one hour. This solution is:
- compliant with CERIB form 71 (March 2008)
- non-polluting, without heat and odour inconveniences, recycling in special waste tanks or extraction hoods
- twice as cheap as sulphur
|Dose in weight||
Quantity to surface
1 side of 6 blocks
|PNC||85 %||9180 gr|
|Dry sand < 1mm||15 %||1620 g|
|Tempo (setting retardant)*||0.7% of the cement mass||64 g|
* available from a building merchant
- Dry-mix cement, dry sand and Tempo to homogenise the mix.
- Add water and mix for 1 minute.
- Setting time: around 10 minutes at 20°C, 20 minutes at 10°C and 5 minutes at 30°C
Follow CERIB instructions.
The block is compression-tested when mortar strength reaches the desired resistance in the block. Progression in strength of Prompt natural cement mortar: 1 hour: 12 MPa, 3 hours: 16 MPa
- do not remix after setting has begun
- avoid excess water
- keep sacks closed after use
- during hot weather, work with cold water and sand stored away from sunlight