The SANAWALL system, thanks to the synergy between the various products that compose it, is able to combine, in a substantially mineral cycle: energy efficiency, lasting performance, improvement of living comfort and high decorative value.
The SANAWALL system is a complete cycle of heat-insulating plastering and heat-reflecting finishing, consisting of a package of products, each with its own specific function. The system is inspired by the traditional executive techniques of the Italian construction culture, revisited in a modern key with the use of green-building and highly performing raw materials.
The SANAWALL system is basically composed of: base coat, plaster, smoothing and finishing.
- The base coat is made with UNTERSANA mortar, tough and extremely resistant to salts.
- The body of the plaster is made with SANAWARME, the real thermal insulation shield, with exceptional thermal conductivity values and CE 998/1 certificate (“mortar for insulation class T1” maximum insulation class <0.1 W/mK).
- The smoothing is made with a fiber-reinforced skim coat, highly breathable and containing light, heat-insulating spherical aggregates with a low modulus of elasticity.
- The finish, depending on the aesthetic needs, can be made with a nanotechnological plaster, with potassium silicates or siloxanes, or with a potassium silicate or siloxane paint, all formulated with glass micro spheres that give a very high index of reflection (SRI) and exceptional breathability.
Breathability is one of the elements that differentiate this heat-insulating system from the majority of traditional “coats” on the market.
In the restoration of masonry, the transpiration to water vapor of materials is a very important parameter that must be carefully evaluated. In materials, breathability is most often indicated with the coefficient μ, dimensionless, with the assumption that the air has value μ = 1. To summarize, this means that the coefficient μ of a material indicates how many times its resistance is greater to the passage of water vapor, with respect to a volume of air of equal thickness. To give some significant numbers and to be able to make some comparisons on common building materials, we can recall some values of breathability μ:
- wood fiber ≈ 7
- brick ≈ 10
- expanded polystyrene ≈ 50
- polystyrene ≈ 70
- concrete ≈ 90
- extruded polystyrene ≈ 120
To ensure good living comfort in the interior, maintaining a good level of water vapor exchange between internal and external masonry is an established concept. This mechanism of vapor passage and transpiration of the masonry system becomes absolutely basic in certain areas of intervention:
- in the restoration of historical walls, which often live with high percentages of humidity inside them;
- in the restoration of masonry affected by capillary rising water phenomena, coming from the ground in contact with the foundations;
- in the remaking of plastering in environments with a high production of water vapor;
- in the plastering of cold spots, where thermal bridges are possible with the production of condensation.
In these specific cases, any restoration work should be carried out using specific mortars (plasters), with a high capacity to transmit water vapor. To cope with the situations listed above, the European standard EN 998-1 identifies two specific categories of mortars/plasters: “ restoration mortar ” and “thermal insulation mortars“. Specifically, the European legislation defines the mortars in question with this terminology:
- restoration mortar: “mortar designed for internal/external plasters used on damp masonry walls containing water-soluble salts. These mortars have a high porosity and vapor permeability and a reduced capillary action “;
- thermal insulation mortars: “guaranteed performance mortar with specific insulating properties”.
In mortars for restoration and thermal insulation, the breathability must be certified by a third-party control body and must have a value μ ≤ 15, as specified by the same EN 998/1 standard.
Our specific mortars, the one for restoration, CALEOSANA, as well as the one for thermal insulation, SANAWARME, have a certified value of transpiration to water vapor μ = 9, therefore they are extremely breathable materials. Faced with these exceptional breathability values of SANAWARME and CALEOSANA, we took a further step and, in asking ourselves some questions, we wanted to test an entire sanitation system.
The questions we wanted to clarify were:
- since in all restorations a simple plastering with restoration plaster is never carried out, but PLASTERING SYSTEMS are carried out which frequently involve consolidating base coat (before the restoration plaster) and smoothing, as well as painting (after the plaster restoration has been laid), how can all these preliminary and subsequent operations, before and after laying the restoration plaster, affect in terms of breathability?
- in theory, the preliminary consolidation and finishing operations are all operations which, considering the specific products and application techniques (energetic spray, counterbore, etc.), can “block” the transmission of water vapor; what will be the µ of a complete restoration and renovation system?
Using all the products of a system, from the initial consolidating ones to the final finishing ones, is it possible to maintain a value of breathability as close as possible to the value indicated for the restoration plastering?
We therefore decided to test the μ-value of the SANAWALL SYSTEM:
- The results obtained by the SANAWALL system (comprising a strong base coat, an insulating plaster, a skimming and a colored finish) testify to excellent breathability values of the entire package, with a value μ = 16 (in practice what is required by the specifications on renovation mortars).
- Since SANAWARME plaster has the same μ = 9 as CALEOSANA plaster, this value can also be extended to a system that includes CALEOSANA instead of SANAWARME.
- This breathability can also be expressed with the value of 58 g/m2/day. Supporting a practical example, it means that only two 3m x 4m walls, plastered with the SANAWALL SYSTEM, are able to transmit about 1400 gr of water vapor/day, sufficient to dispose of the steam produced in rooms with large production of water vapor (kitchen, bathroom, laundry, etc.).
- The use of the SANAWALL SYSTEM in the restoration of historic walls deserves a more detailed reflection. The renovation of historic buildings is often a very complex operation, with unexpected variables that make it more complex than the construction of new buildings. The operation becomes even more demanding when the property to be restored is subject to protection and when the design has objectives of sustainability and respect for the environment. In order to meet these objective needs, UNI EN 16883 was published: “Guidelines for improving the energy performance of historic buildings”. These European-issued Guidelines dictate the design approach for interventions aimed at improving the energy efficiency of historic buildings, focusing attention on respecting the typical characteristics of the building elements, namely:
– spatial configurations,
– the look,
– building construction,
– the existing construction systems intended as distinctive elements.
On the basis of this approach, it is evident that the improvement of the energy performance of a historic building cannot be conceived and implemented with paneled systems consisting of synthetic products with a low density, such as polystyrene, eps, which, in addition to distorting the distinctive “plaster” element, significantly modify, worsening them, the hygrometric and transpiration parameters of the entire masonry package.
Having made these premises, considering the compositional and performance qualities of the system, the SANAWALL SYSTEM is a REFERENCE TECHNOLOGY in the context of historic buildings and all buildings subject to protection, in plastering-finishing interventions with specific insulating properties.