|This method is particularly suitable to ensure optimum bonding even on smooth surfaces. Spraying is recognized as the best method of application allowing sharper sands and lower water content in the mortar mix. The speed of work is considerably increased and an average of 1000 square feet per day per man is quite normal. The pressurized application also allows to build up the thickness of a layer to 1″. The pressure should not exceed 3.5 Bar*. Two coat work is normally sufficient with the use of a spray gun.|
Overall render thickness
|3/4″-1″||1″-1 3/8″||up to 1 9/16″|
|On surfaces with low keying||(for thickness above 1 9/16″
please consult us.)
NHL 5 or NHL 3.5 @ 1: 1.5
Sands: well graded 5mm down to 0.075
|Leave 24/48 hours as sprayed to provide good key|
NHL 3.5 @ 1:2 or NHL 5 @ 1:2.5
Sands: well graded 3mm down to 0.075
|Leave for a minimum of 4 days depending on weather conditions, coat thickness and the plasterer’s judgment.
Level using a straight edge and key with criss-cross pattern.
If this is also the finishing coat (3/4″-1″), depending on the finish required, a finer sand can be used (#6 to #200 mesh).
|2nd coat (finishing coat)||3/16″-5/16″||3/16″- 3/8″||3/16″-3/8″|
|NHL 3.5 @ 1: 2.5 or NHL 2 @ 1:2
Sands: #6 mesh down
Finer sands for wooden float or smooth finishes (#8 or finer) can be used. In these cases the thickness should not be over 3/16″.
|Notes: background preparation as per good practice. Always dampen surface before each application. On high suction background ensure that this is thoroughly dampened (no standing water on surface), if necessary several times, to minimise shrinkage. Cure work for few days with water mist. Protect against rain, frost, drying wind and direct sun for 2 to 7 days. If dubbing out is required the mortar ratio should be the same as the 1st coat. Leave dubbed out areas as sprayed to provide a key.*Sablon S3 Hopper gun|