Sometimes we are faced with old walls rolled up with improvised systems without any coding. Coats without protective coating, coats with insufficient or inadequate layers of smoothing products. Insulating systems with not overlapped net, without any tessellations. In such burdensome situations it is usually convenient an important restoration, that also includes the detachment of the entire crust formed by the smoothing net and covering: the whole construction of the system must be restarted from the intact surface of the insulating panels.
1. Completely detach the entire smoothing layer, net and coating until the panels are bare.
2. Check the tightness of the slabs on the support, with the replacement of any panel that is not perfectly adherent or starts detaching.
3. Dust the surface with compressed air.
4. Foam any crack or gap between each panel with suitable polyurethane foam.
5. Apply with a brush or roller a coat of water-based fixative, micro-emulsified, acrylic with strong penetration, appropriately diluted, FIXACRIL, suitable to be used within cementitious plasters, bastard mortar and concrete. Yield about 10-15 m2 / L.
6. Nail again all surfaces with fasteners of appropriate length at a rate of at least 6 per m2.
7. Before smoothing, apply corner bead with adhesive mortar, primed fiberglass mesh in correspondence of all the turn-ups (edges of the facades and window contours) in order to protect the corners from accidental impacts.
8. Realization of the reinforced thin plaster through application on insulating panels, of smoothing mortar and subsequent drowning of a reinforcing mesh in alkali-resistant glass fiber 161A prepared with 160 g / m2, applied up-side down and drowned in the shaving layer with the technique of "cool on fresh"; the net must be drowned between two layers of shaving while the edges must be overlapped by about 10 cm, in order to guarantee a uniform resistance.
Near doors and windows must be applied an additional oblique reinforcement (45°) of the armour net in order to avoid the formation of cracks near the corners, where the concentration of the mechanical effort is higher.
On the major spots of contact (such as skirting and lower bases in general), if you want to increase the impact resistance, we advice to overlap two layers of net (the first drafted upside-down, the latter horizontally) following the "glue/net/glue" executive method.
The adhesive smoothing products which can be used are:
When the smoothing products are completely dry, you can go on with the realization of the finishing layer and the application of the protective coat. The finishing solutions, apart from giving the structure the desired aesthetic aspect, have the function to protect the system from atmospheric agents, ensuring its long-lasting resistance through years. The finishing cycle consists on the application of plasterwork, which can be chosen between the various Paulin lines such as the Acrylic one, the Acrylic-siloxane, the Siloxanic with the proper pigments and grain for every kind of project and need.
We suggest to choose a light finishing colour with a reflectance index (Y) higher than 30. Will be expected vertical and horizontal interrupting stripes in order to not highlight defects caused by restarts and applications. The smoothing plasterwork pastes that can be used are all complying with the EN 15457 (fungi growth-resistance) e EN 15458 (algae growth-resistance) regulation.