ABNT NBR 9574 - Waterproofing Execution
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We are here today to talk about another technical standard, the NBR 9574. If you are in the civil construction business, you know that it is a well-known standard, since it deals with the execution of waterproofing, that is, it describes the procedures that must be used to obtain a perfect waterproofing system according to each type.
At Blok, we always like to stress the importance of knowing and applying the methods developed by the standards, as they guide all processes, considering every detail. Therefore, when following the recommendations detailed in the rules, the chances of having to face problems tend to be lower, right?
Therefore, our mission today is to bring you NBR 9574 so that you can learn everything about the execution process of waterproofing. First of all, we have to understand what it's about, specifically. Let's go to the initial concepts that NBR 9574 says, okay?
ABNT NBR 9574 establishes the requirements and recommendations related to the execution of waterproofing to meet the minimum construction protection conditions against the passage of fluids, as well as the health, safety and comfort of the user, in order to guarantee the watertightness of the construction parts that require it.
Thus, the standard applies to buildings and constructions in general, under construction or subject to addition or reconstruction, or even to those undergoing renovations or repairs.
First of all, we have to clarify that each type of waterproofing requires a type of execution. For this reason, the standard divided the execution processes into topics according to the type of waterproofing system, separating rigid and flexible waterproofing. So, following the norm, let's do it the same way, right?
Before we begin to understand each process, the standard contains some general concepts that must be considered before any procedure, namely: areas that require watertightness must be fully waterproofed; for types of waterproofing that require dry substrate, the regularization mortar must be at least 7 days old; surfaces subject to water under positive pressure must be waterproofed on the acting surface of the water.
Now let's start with the rigid type of waterproofing systems and then move on to the flexible type.
The substrate must be firm, cohesive and homogeneous. In addition, it must be clean, free of foreign bodies, remnants of formwork, hardware tips, remnants of mold release or impregnating products, faults and nests. The elements passing through the substrate must be attached beforehand.
The substrate must also be moist, but free of film or water spray. When water is sprayed, capping with cement and quick-setting additive should be promoted.
The substrate must be moistened and receive a layer of Chapisco of cement and sand, 1:2 trace, to serve as an adhesion bridge between the substrate and the mortar waterproof with water repellent.
The mortar must be prepared on site and must not be industrialized, consisting of sand, Portland cement, water repellent additive and drinking water.
The washed sand must have a grain size of 0.075 mm to 3 mm, classified as medium, free of clay substances or materials.
The trace, the type of cement and sand, and the handling time must be in accordance with the manufacturer's specifications.
The waterproof mortar must be applied continuously, with a thickness of 30 mm, and the application in successive layers of 15 mm, avoiding overlapping of the execution joints.
The first layer must have a ribbed finish in order to provide an anchoring surface for the subsequent layer, and the waterproof mortar is manually pressed against the surface to eliminate the void index as much as possible.
Both layers must be performed on the same day; otherwise, the last layer must be preceded by chapisco.
When there is discontinuity due to interruption of execution, the joint must be chamfered and plastered beforehand.
The last layer must be finished with the use of a cutter and the mortar must cure for a minimum of 3 days.
Mechanical protection is recommended in places where there is a possibility of mechanical aggression.
The preparation of the substrate must be done as explained in sub-item 1.1. Go back there to understand!
The mortar to be used must be prepared on site, by mixing binder, aggregate and polymer.
The trace, type of cement and sand, time of use of the mixture and cure must be in accordance with the manufacturer's specifications.
The concrete substrate, when horizontal, must be moistened and given a priming layer with a polymer composition and Portland cement. The polymer must be pre-diluted with water according to the polymer manufacturer's specification.
The need for printing and its methodology must be in accordance with the manufacturer's instructions.
The concrete substrate, when upright, must be moistened and receive a layer of chapisco before applying the polymer-modified mortar.
The masonry substrate must be moistened and coated with chapiscus prior to the application of the polymer-modified mortar.
The thickness of the polymer-modified mortar must be at least 1.0 cm.
In open areas or under solar exposure, promote the hydration of the modified mortar for at least 72 hours.
It does not require protection in places where there is a possibility of mechanical aggression.
The preparation of the substrate must be done as explained in sub-item 1.1. Go back there to understand!
Gradually add the powder component to the resin component and mix homogeneously, manually or mechanically, dissolving any possible lumps.
Once the powder and resin components have been mixed, the time of use of the mixture should not exceed the period recommended by the manufacturer.
Apply the polymeric mortar coats crosswise to the substrate, with intervals of 2 to 6 hours between coats, depending on the ambient temperature. If the previous coat is dry, wet the place before applying it again.
When using screen-like armor, it must be positioned after the first coat and be completely covered by subsequent coats.
In open areas or under solar exposure, promote the hydration of the polymer mortar for at least 72 hours.
Dosage, consumption, mixing and handling time, application tools, drying between coats and curing must follow the manufacturer's recommendations.
Mechanical protection is recommended in places where there is a possibility of mechanical aggression.
The substrate must be made of concrete and be firm, cohesive and homogeneous. In addition, it must be clean, free of foreign bodies, remnants of formwork, hardware tips, remnants of mold release or impregnating products, faults and nests.
The substrate must be saturated, but it must be free of film or water spray. If there is a water jet, promote capping with cement and quick-setting additive.
Mix the cement with quick-grip additive with water in a container, in the proportion indicated by the manufacturer, until a paste with a smooth and uniform consistency is formed.
Apply a coat with a brush, broom or brush.
Immediately on the cement layer with the quick-setting additive, while still wet, rub the cement with the ultra-fast dry additive onto the treated surface, hard and over again until a thin layer of dark and uniform color is formed.
If the water continues to penetrate at any point, repeat the plugging with cement with an ultra-fast additive, until obtaining watertightness.
Immediately apply a coat of liquid sealant, until the surface becomes shiny.
Immediately over the sealing liquid, which is still shiny, apply a coat of cement paste with quick-grip additive prepared according to the previous procedure.
Wait 20 minutes and apply another layer of cement with quick-setting additive in the cross direction with respect to the previous coat.
Dosage, consumption, mixing and handling time, application tools, drying between coats and curing must follow the manufacturer's recommendations.
Mechanical protection is recommended in places where there is a possibility of mechanical aggression.
The same procedures that we mentioned in the topic of polymer mortar must be followed. Go back there!
For both negative and positive pressure water, the substrate must be firm, cohesive, and homogeneous. In addition, it must be clean, dry, free of foreign bodies, remnants of formwork, hardware tips, remnants of mold release or impregnating products, faults and nests.
Gradually add components hardener and resin and mix homogeneously, mechanically or manually.
Once the components have been mixed, the time of use of the mixture must not exceed the handling time.
Apply coats to the substrate, with a maximum interval of 24 hours between coats. If it exceeds the maximum range, promote surface sanding.
When using screen-like armor, it must be positioned after the first coat and be completely covered by subsequent coats.
Dosage, consumption, mixing and handling time, application tools, drying between coats and curing must follow the manufacturer's recommendations.
Mechanical protection is recommended in places where there is a possibility of mechanical aggression.
We have completed the procedures for carrying out waterproofing of rigid types. Now, let's understand how the processes of flexible waterproofing types take place. Shall we go, there?
The substrate must be firm, cohesive, dry and regular, with a slope in horizontal areas of at least 1% towards the water collectors. For gutters and indoor areas, a minimum of 0.5% is allowed. The corners should be in half a cane and the edges should be rounded.
In addition, the substrate must be clean, free from foreign bodies, remnants of formwork, hardware tips, remnants of mold release or impregnating products, faults and nests.
Apply a coat of the printing product with a sheepskin roll, brush or brush, evenly, waiting for complete drying.
Heat the asphalt homogeneously with suitable equipment at a temperature between 190°C and 220°C.
Apply a coat of heated asphalt using jute yarn skewer. Extend the structure with a minimum overlap of 10 cm, applying the necessary layers of heated asphalt to its saturation. If there is more than one structurant, repeat the procedure.
Consumption, drying between coats, tools, and safety instructions must follow the manufacturer's recommendations.
There must be protection when subject to the incidence of ultraviolet rays and structural mechanical protection with a mesh of galvanized wire or plastic wires in vertical areas. In horizontal cases, armed mechanical protection must or must not be performed on a separating layer and/or draining layer, in places where there is a possibility of mechanical aggression.
Substrate preparation should be done as in topic 7.1. Take a look there.
The application takes place as in the previous topic also, in 7.2, but the temperature must remain between 160°C and 180°C.
The protection follows the same as described in topic 7.3.
Substrate preparation should be done as in topic 7.1. Take a look there.
Apply a coat of the printing product with a sheepskin roll, brush or brush, evenly, waiting for complete drying.
Apply a coat with a sheepskin roll, brush or brush, homogeneously, and extend the structure with a minimum overlap of 10 cm. Wait for drying. Apply subsequent coats, respecting the drying time, until the recommended consumption is reached and ensuring full coating of the structuring agent. If there is more than one structurant, repeat the procedure.
Consumption, drying between coats, tools, and safety instructions must follow the manufacturer's recommendations.
The protection follows the same as described in topic 7.3.
The same procedure described in topic 7.1 should be followed. Go back there!
The same procedure described in topic 9.2 should be followed.
The protection follows the same as described in topic 7.3.
The same procedure described in topic 7.1 should be followed. Go back there!
The same procedure described in topic 9.2 should be followed.
It does not apply a polychloroprene and chlorosulfonated polyethylene coat to protect against the incidence of ultraviolet rays.
The same procedure described in topic 7.1 should be followed. Go back there!
The same procedure described in topic 9.2 should be followed.
The protection follows the same as described in topic 7.3.
The same procedure described in topic 7.1 should be followed. Go back there!
The same procedure described in topic 9.2 should be followed.
The protection follows the same as described in topic 7.3.
The same procedure described in topic 7.1 should be followed. Go back there!
Apply a coat of the priming product with a sheepskin roll, brush or brush, homogeneously, waiting for complete drying if the substrate is wet.
Apply evenly with a sheepskin roll, squeegee or mechanical equipment. If necessary, extend the structure with a minimum overlap of 10 cm and apply the subsequent coat (s), until the recommended consumption is reached and ensuring the total coating of the structure. If there is more than one structurant, repeat the procedure.
Consumption, drying between coats, tools, and safety instructions must follow the manufacturer's recommendations.
The protection follows the same as described in topic 7.3.
The same procedure described in topic 7.1 should be followed. Go back there!
If there is more than one component, add them, mixing homogeneously, mechanically or manually. Once the components have been mixed, the time of use of the mixture must not exceed the handling time. Apply a coat of priming to the substrate, if necessary, and wait for drying. If a structurant is used, it must be positioned after the first coat of the product and be completely covered by subsequent coats.
Dosage, consumption, mixing and handling time, application tools, drying between coats, and curing must follow the manufacturer's recommendations.
Mechanical protection is recommended in places where there is a possibility of mechanical aggression.
The same procedure described in topic 7.1 should be followed. Go back there!
Follow the procedure described in 14.2.
The protection follows the same as described in topic 7.3, except for membranes with resistance against ultraviolet rays.
In addition to the conditions already described in topic 7.1, the substrate must be moist, but it must be free of film or water spray. Also, the elements passing through the substrate must be attached beforehand.
Gradually add the powder component to the resin component and mix homogeneously, manually or mechanically, dissolving any possible lumps.
Once the powder and resin components have been mixed, the time of use of the mixture should not exceed the period recommended by the manufacturer.
According to the manufacturer or designer's recommendation, position the structuring after the first coat. Apply subsequent coats.
Mixing, consumption, handling time, tools, drying between coats, curing, and safety instructions must follow the manufacturer's recommendations.
The protection follows the same as described in topic 7.3.
The substrate must be firm, cohesive, dry and regular, with a slope in horizontal areas of at least 2% towards the water collectors. Corners should be in half a cane and the edges should be rounded.
It must also be clean, free of foreign bodies, remnants of formwork, hardware tips, remnants of demoulding or impregnating products, faults and nests.
Apply a coat of the priming product with a sheepskin roll, brush or brush in a homogeneous manner, waiting for its complete drying, which may be a polymer-modified cement, a polymer mortar or the diluted product itself, according to the manufacturer's recommendations.
Apply a coat with a sheepskin roll, brush or brush, evenly and extend the structure with a minimum overlap of 10 cm. Wait for drying. Apply subsequent coats, respecting the drying time, until the recommended consumption is reached and ensuring full coating of the structuring agent.
Consumption, drying between coats, tools, and safety instructions must follow the manufacturer's recommendations.
The acrylic membrane must be exposed.
The substrate must be prepared according to the procedure described in topic 7.1.
Apply a coat of the priming product with a sheepskin roll, brush or brush evenly, waiting for complete drying, except in cases of blankets not adhering to the substrate.
It is recommended that asphalt blankets be applied at ambient temperatures above 5°C, unless specifically advised by the manufacturer.
Unroll the coils, aligning them and rewinding them again, on the substrate to be waterproofed.
Consumption, handling, tools, and safety instructions must follow the manufacturer's recommendations.
The torch to be used in the application must have a flame control trigger, a 50 cm rod, a 2" nozzle. Direct the torch flame in such a way as to simultaneously heat the primed substrate and the adhesive face of the blanket. Press the blanket from the center towards the edges to expel any air bubbles. The overlays must be at least 10 cm, sealing the seams with rollers, spatulas or a rounded-pointed mason spoon.
Take the necessary precautions so that the intensity of the flame does not damage the blanket Asphaltic and provide adequate adherence of the blanket to the substrate.
Heat the asphalt homogeneously in suitable equipment at a temperature between 180°C and 220°C for asphalt without the addition of polymers and 160°C to 180°C for asphalt with the addition of polymers. Apply a coat of asphalt heated to a minimum temperature of 160 °C, with the use of jute yarn, to the primed substrate at a maximum distance of 1.00 m in front of the reel. Asphalt must be applied to the substrate and underside of the coil. Press the blanket from the center toward the edges to expel any air bubbles. The overlays must be at least 10 cm, sealing the seams by applying an asphalt bath, with the use of jute yarn skewer, pressing the seams with rollers, spatulas or a rounded-pointed mason spoon.
Apply a homogeneous layer of adhesive to the primed substrate and to the face of the asphalt blanket to be adhered to the substrate. Wait for the adhesive to set and press the blanket against the substrate, pressing from the center toward the edges, to eliminate any air bubbles. The overlays must be at least 10 cm, sealing the seams with rollers, spatulas or a rounded-pointed mason spoon.
Remove the non-stick element, promoting initial adhesion to the substrate, and continue the process by removing the film and adhering to the blanket simultaneously. Perform the process slowly and press from the center toward the edges to expel any air bubbles. The overlays must be at least 10 cm, pressing the seams tightly with metal rollers.
a) Promote structured mechanical protection with galvanized wire or plastic mesh in vertical areas. For horizontal ones, mechanical protection, armed or not, must be performed on a separating and/or draining layer, in places where there is a possibility of mechanical aggression.
b) Promote protection against ultraviolet rays, except for self-protected blankets.
The substrate must be firm, cohesive, dry, regular, clean, free of foreign bodies, remnants of formwork, hardware tips, remnants of release or impregnating products, faults and nests, with a slope in horizontal areas of at least 1% towards the water collectors. For gutters and internal areas, a minimum of 0.5% is allowed. Corners should be in half a cane and the edges should be rounded. In the case of Surface irregular where it is not possible to execute an adjustment layer, a crib layer must be used.
Open the rolls or panels of polyvinyl chloride (PVC) blankets. The overlays must be at least 10 cm, sealing the seams by chemical welding or thermofusion, with an overlap of 5 cm (single or double cord). Consumption, handling, tools, equipment, mechanical fixings, and safety instructions must be in accordance with the manufacturer's recommendations. Perform the mechanical fastenings and compartments with the accessories determined by the manufacturer.
a) Promote structured mechanical protection with galvanized wire or plastic mesh in vertical areas. For horizontal ones, mechanical protection, armed or not, must be performed on a separating and/or draining layer, in places where there is a possibility of mechanical aggression.
b) Promote protection against ultraviolet rays, except for blankets that are resistant to ultraviolet rays.
Follow the procedures described in 20.1.
Unroll the rolls by aligning them on the substrate to be waterproofed. Perform the welds, which can be of the following types: chemical welding with a minimum overlap of 7.5 cm or thermofusion with an overlap of 10 cm (single or double cord). Consumption, handling, tools, equipment, mechanical fixings, and safety instructions must be in accordance with the manufacturer's recommendations.
Promote structured mechanical protection with galvanized wire or plastic mesh in vertical areas. For horizontal ones, mechanical protection, armed or not, must be carried out in places where there is a possibility of mechanical aggression.
Follow the procedures described in 20.1.
Apply one coat of the priming product with a sheepskin roll, brush or brush, homogeneously, waiting for complete drying, except for the cases of blankets not adhering to the substrate. Open the rolls of ethylene-propylene-diene-monomer (EPDM) blankets, lining them up.
The overlays must be at least 5 cm, making the seams by applying a monoadhesive and heating tape.
Consumption, handling, tools, equipment, mechanical fixings, and safety instructions must be in accordance with the manufacturer's recommendations.
Follow the procedures described in 20.3.
Follow the procedures described in 20.1.
Follow the procedures described in 21.2.
Follow the procedures described in 21.3.
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Today, we brought NBR 9574 here to let you know how waterproofing procedures should be performed according to each type, divided into rigid and flexible. So, before starting the work, consult this article, to ensure better results and avoid future problems! The rules are there to be consulted and followed! Therefore, have them in hand before starting any work. And if you need it, count on Blok for any challenge. Until next time!
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