simprolit ^®

Simprolit blocks are fixed "dry" without plastering between the rows. Upper and lower surface of the blocks are even and the blocks have constant hight and accurate dimensions which means that there is no need for a thick plaster layer to level the wall surface. It also improves thermo-insulating properties of both the blocks and the complete wall. Hollow block cavities can be filled up with concrete, mortar or Simprolit - thus taking the role of a bonding element.

Simprolit blocks are fixed "with bonding on 1/2 block" and the hollow cavities of each row must exactly coincide with the hollow cavities of the next row of blocks - which has to be strictly controlled. In this manner, the mass of casted concrete forms a vertical system of "concrete posts" between the floor and the ceiling (slab or roof plate).

On the surface of Simprolit blocks there are horizontal longitudinal chanels which are used for installation of Ø8mm reinforcement and afterwards are filled up with mortar or concrete. Function of the steel reinforcement is to build "reinforced concrete truss" made of vertical concrete posts and horizontal reinforcement chords - forming a wall that is rigid in its own plane - which often represents a desired wall charasteristic, especially in seismically active regions.

Simprolit blocks are easily cut and brought to the required dimensions, always paying attention that the above mentioned request (vertical hollow cavities of each new row must exactly coincide with the hollow cavities of the previous row of blocks) should be fulfilled as well as the rule by which the blocks forming a new row must be fixed with bonding on ? block from the previous row.

Building with Simprolit blocks requires strictly even and horizontal surface. Therefore, the building surface must be prepared by application of a 10-20mm thick cement plaster layer. This layer must be leveled both longitudinally and transversally. The building is to be continued only when the plaster becomes hard.

In case that there is a horizontal waterproofing between the wall and the floor foreseen in the project, it has to be applied either as a waterproofing layer between two levelling plaster layers or as a waterproof mortar for surface levelling.

When standard Simprolit blocks (type "SB", "SBD" and "SPB") are used, one must especially consider that cement plaster or glue must be brought on vertical block surfaces in 5-6mm thick layers (to avoid air blowing through the vertical joints). On the other hand, when special Simprolit blocks series "S" (type "SBS", "SPBS" and "SBDS") are applied, the same problem is solved by using vertical transversal styrofoam or Simprolit pads.

Except for building with Simprolit blocks which hollow cavities are filled with concrete, mortar or Simprolit polystyrene concrete, walls can also be constructed with Simprolit series "Super" blocks using "dry building" technology. According to this technology, it is recommended to pour the concrete or mortar into hollow cavities of the first row of blocks but only up to the 1/2 of their height. After that, special styrofoam or Simprolit pads made of one-layer "SOP" plates and cut to fit blocks' hollow cavities are inserted into these cavities. In this way, the pads stick out from the first row of blocks by 1/2 of their height - becoming specific guides for construction of the next row of blocks, but also providing a stiff connection between two adjacent rows as well as preventing sound penetration, frosting and blowing through the joints.

When exposed to extremely low temperatures, walls made of Simprolit blocks may be constructed using warm Simprolit polystyrene concrete for filling of the hollow cavities. However, the difference between heating up the regular concrete and Simprolit must be underlined. Namely, in case of the regular concrete it is essential to warm up the aggregate (because of its high heat capacity), but for Simprolit polystyrene concrete it is enough to use just hot water (with maximum temperature 70°C in the boiler or 60°C in the fresh concrete mass). Warmed up and poured into blocks' vertical hollow cavities, Simprolit polystyrene concrete is placed into some kind of «thermos», providing (together with additional heat which is released during chemical reaction between cement and water in the process of cement hydration) the necessary hardening cycle of the Simprolit polystyrene concrete without any risk of freezing. Besides the described vertical cutting of Simprolit blocks (in case of blocks' overlapping or building between concrete columns and reinforced concrete walls) it is also possible to cut the blocks horizontally. This procedure is recommended in the following situations – if the parapet height under the window does not coincide with the height of the whole row of blocks, or if the height of the whole row of blocks does not coincide with the distance between two slabs. Simprolit blocks are easily cut horizontally and brought to the required dimensions. However, if more then 2/3 of the complete height of the blocks in the last row should be cut off, it is recommended to equally cut not only one but two of the last rows, bringing the blocks in both rows to required dimensions.

Building with Simprolit blocks in seismically active regions must be performed in the following manner: two horizontal reinforced concrete ring beams are formed along the height of the wall (the lower beam at the level of window or door lintel, and the higher beam at the slab level), or else in every row of Simprolit blocks o8mm horizontal reinforcement should be installed. Both of the recommended solutions provide more uniform seismic load distribution and contribute to the general bearing capacity of the walls.

If the Simprolit blocks are reinforced with horizontal or vertical steel reinforcement, it is essential to cover it with either concrete or cement mortar (with cement content higher then 200 kg/m3), in order to protect the reinforcement from possible corrosion.

The horizontal lintel over the window opening has to be reinforced with minimum two Ø8mm rebars. These rebars should be at least 15cm longer on both sides then the window opening and should be anchored into adjacent concrete posts formed by Simprolit blocks. On the other hand, the horizontal reinforced concrete ring beam at the slab level should be reinforced with four o12mm rebars and o6mm stirrups at every 24cm along the whole length of the beam (unless it is differently specified in the Design).

In seismically active regions it is also neccesary to build vertical reinforced concrete ring beams at the walls' end (at the corners of the building or at other wall-joints). These vertical reinforced concrete ring beams should be reinforced with four Ø14mm rebars and Ø6mm stirrups at every 15cm along the whole height of the beam (unless it is differently specified in the Design).

Plaster is an important element of the general structure of the wall - therefore it is necessary to pay special attention to its design and application.

Plasterwork can fix, but also spoil some of the wall's properties, such as: steam permeability, frost resistance, condensation effects, physical-mechanical characteristics, etc. In that regard, fundamental influence have plaster quality, composition and especially thickness of the placed layer.

The thickness of the plaster, as well as the relation between outer and inner plaster layer dimensions, have significant importance when the walls are designed and built using steam-permeable materials, such as: brick, cell-concrete (gas concrete - siporex, foam concrete), polystyrene concrete, etc.

In regard to the fact that plaster layers slow down the steam and air conduction, the above mentioned walls must be designed and built to provide that the quantity of steam that enters the wall through the inner plaster layer and the quantity of steam that comes out through the outer plaster layer are exactly the same.

In that case the walls "breathe" and the steam does not stay inside the wall or under the outer plaster layer. On the contrary, the same steam just after several freeze-thaw cycles, becomes the basic cause of crack development and outer plaster spalling or else there is a moisture and mildew appearance on the inner side of the wall, especially at the thermical "cold bridges" - horizontal and vertical ring beams, window lintels, wall and ceiling joints, etc.

If there is no detailed thermo-technical calculation present, it is possible to use the old rule of the experienced craftsmen: in order to make the walls "breathe" it is recommended that the inner plaster layer should be twice as thick as the outer (for instance, if the outer plaster layer amounts to 2 cm, then the inner layer should be 4 cm thick).

Among the other advantages, building with Simprolit blocks does not require thick plaster layers – dimensions of outer and inner plaster layers stand in relation 2:3, whereas the sufficient outer layer should be between 6mm - 10mm thick (or the outer side of the wall could just be skimmed using cement glue or cement paste mixed with some fine sand) and proportionally inner plaster layer should be 10 - 15mm thick.

Plasterwork on Simprolit blocks can be done using any of the usually applied plastering materials and the plastering technology depends only on the selected material technology.

The fact should be pointed out that the walls made of Simprolit blocks do not absorb moisture and the plaster dries toward the outside. On the other hand, drying of the plaster placed on the walls made of other materials is achieved so that half of the moisture evaporates to the outside and the other half to the inside of the wall. Because of that, the plaster layer put on the Simprolit wall dries longer, giving us the opportunity to fine-level (skim) the same layer. There is also another difference: if the walls are built using standard materials the plasterwork is executed in three phases (ground - prime coat, first layer of coarse plaster and finishing layer of fine plaster). On the other hand, when the walls are built using Simpolit blocks, plasterwork is executed in only two phases (first phase consisting of backfilling of inclined vertical joints and prime-coating, second phase consisting of actual plastering together with fine-leveling finish).

Rough surface and cement based structure of Simprolit blocks makes it possible to lay the inner walls with ceramic tiles or even heavy and large ceramo-granite plates, without additional anchoring - using any of the cement based types of ceramic tile glue.

If the outer sides of the facade walls are tiled with steam non-permeable material it is necessary to find a way for steam to leave the wall and exit to the atmosphere. This goal could be achieved in two ways:

Principally, finishing of walls made with Simprolit blocks can be done using any of the chosen finishing materials.

The walls may also be painted using any of the steam permeable paints, even without previous skimming (although this solution is usually not recommended mostly for economic reasons, because to much paint gets spent due to the rough block surface; it is much more cost-effective to skim the block surfaces even with the mixture of cement paste and fine sand, prior to wall painting).

Walls made of Simprolit blocks are easy to connect with other adjacent walls, made of either Simprolit blocks or any other structural material.

Generally, construction of joints at the connection of two adjacent walls is very simple - it is accomplished by using mortar or cement based glue, together with steel anchors. These anchors have to be installed into the adjacent wall and their position must coincide with the position of horizontal openings (channels) of every third (or fourth) row of Simprolit blocks where there is already present the required horizontal reinforcement.

Considering the fact that Simprolit blocks are easily cut, worked with and brought to the required form and dimensions, there are several other ways to connect Simprolit block walls with any other adjacent wall. For example, it is possible to make the connection using o6-o8 mm steel reinforcement, bent in a shape of «Г» letter, which is layed in the same direction at the corners of the building and in other cases in the opposite direction (every second row - alternately).

Simprolit blocks type "SBD" and "SBDS" have .

Simprolit walls consist of "dry" fixed Simprolit blocks - without any horizontal plaster layer, using "bonding on 1/2 block" to make connection with the blocks from the previous row and filling up the hollow block cavities with fresh concrete, mortar or polystyrene concrete.

In that way, the net consisting of vertical concrete "posts" is formed all along the wall's height. On the other hand, the plaster layed on the Simprolit block wall can easily sustain (without deformation) shear load caused by lighter objects such as pictures, clocks, lamps, etc. These objects may be fastened to plastered Simprolit block walls using customary plastic plugs.

In the case of heavy objects fastening, special steel plugs have to be used. These plugs must not be installed into the transversal rib of the Simprolit block, but into the "concrete post" made by filling of the block cavities with concrete (concrete posts cover approximatelly 2/3 of the block's width).

In the situation when the anchor has to be placed on the location away from the corresponding "concrete post" (which may be the case if a kitchen cabinet, boiler or any similar appliance has to be fastened to the wall) it is recommended to put first a metal angle bar or a wooden lath (and anchor it to the «concrete posts» formed by Simprolit blocks) and after that it is possible to fasten any heavy appliance to that angle bar or lath.

In any case, both of the described methods are considerably easier and safer then any method of heavy appliance fastening to the hollow brick wall.

Guiding of installations (such as: water and sewer pipes with diameter up to 50mm, flexible ribbed pipes for electric cable lines, other installation networks, etc.) through Simprolit block walls is very simple, because the blocks are easily "slotted", drilled and cut.

After cutting through Simprolit blocks in order to make installation channels, there is always some waste material left. This material should not be thrown away - it could be mixed with cement and water and the mixture could be used as a thermo-insulating mortar for filling up the channels after laying of installations.

One of the many advantages of Simprolit blocks over siporex and other similar cell-concrete blocks has to be underlined - Simprolit contains no lime (presence of lime as a basic ingredient of siporex and other similar materials, causes significant corrosion and destruction of pipes and other metal elements). Therefore, in a wall made of Simprolit blocks it is not necessary to put additional isolation for metal pipe work protection.

As for the installation of vertical sewer pipes (usually with diameter over 50mm) there are two possible solutions:

When building with Simprolit blocks, an experienced Contractor often leaves in each wall a whole vertical ''post'' without concrete filling, which might later become very useful for fitting of an additional vertical installation channel.