How long does self leveling cement take to dry: All About Self-leveling Concrete | ProEst

There are two types of self-leveling compounds; acrylic and water-based concrete. Acrylic concrete is made by mixing cement powder with liquid acrylic polymer. 

The water-based self-leveling concrete uses water instead of the acrylic liquid for mixing. They both come as a bag of powder containing the latex compounds for mixing. The water-based self-leveling concrete type is much easier to use and ideal for beginners. 

Self-leveling concrete is poured in liquid form and spread in place using a gauging tool. A single pass of self-leveling concrete is usually 0.25 to 1.5 inches thick. The finished product is smooth and flat, with superior compressive strength to traditional concrete floors. 

After application, the concrete can be decorated using overlays or concrete stains and dyes. Self-leveling concrete is relatively popular among architects and property owners because of its many advantages over traditional concrete. 

It is easy, quick to install, and useable before or after construction. It also creates smooth and flat floors on tile, plywood, or concrete floors. Therefore, self-leveling concrete helps reduce instances of damage and repair costs.

When to use self-leveling concrete

Self-leveling concrete is quick and easy to install and is therefore quite DIY-friendly. Use self-leveling concrete to repair slightly uneven floors in your home. Use a spirit level to accurately measure the degree of unevenness, then pour the compound and spread it out. 

There are many applications for self-leveling concrete. It is perfect for upcycling settled or cracked floors. You can also use it to smoothen and flatten rough and uneven basement floors. 

You can also use it as a standalone finishing material, durable enough to withhold daily wear and tear. This makes it suitable for use in retail stores, warehouse floors, institutional facilities, and industrial locations. 

For decoration, add stains, pigmented color dyes, and saw cuts, and for a more polished look, consider mechanical polishing.  

When not to use self-leveling concrete

Despite its advantages, self-leveling concrete is not always the best option. There are some instances when you should not use self-leveling concrete. 

Do not use self-leveling concrete without the help of a trained professional. The compound dries very fast and only allows a ten to twenty-minute window from pouring to spreading before it starts to harden. 

Self-leveling concrete is best suited as a standalone or subsurface flooring for interior flooring. However, it is unsuitable for outdoor flooring as it doesn’t hold up very well in harsh conditions.

Polymer-mixed, self-leveling concrete also does not cure very well on non-horizontal surfaces. It will therefore be unsuitable for use on vertical walls. It is also not suitable for use where heavy machinery or harsh chemicals are applied.

It is also advisable to avoid using self-leveling concrete on floors with structural damage.  It only fixes the surface, so the problem will reoccur if the underlying floor orientation is in bad shape. Perform structural repairs before applying the leveler to prevent the floor from sinking again. 

Self-leveling concrete is also unsuitable for repairs in large areas due to its fast drying time and increased cost. A self-leveling concrete bag is more expensive than a bag of ordinary cement. 

Finally, do not use self-leveling concrete unless you can clean it right after application. Concrete is very sticky and can stain surfaces and clothes. 

How to use self-leveling concrete

It is vital to ensure there’s no structural damage before installing self-leveling concrete. If the unevenness is due to structural damage, you must get that fixed first. 

Next, you need to determine the moisture level of the concrete floor. Moisture is normal in concrete, but a high moisture level puts the leveling compound at risk of gradual degradation. The slab must, therefore, be tested to ensure that the moisture level is within acceptable levels. 

This can be done using “the relative humidity test using in situ probes. ” Once you know the floor is good enough to work on, you can start the installation process. Start by preparing the floor and filling the cracks, then apply primer, mix the concrete and leave to dry. 

Prepare the floor

Clear the floor by removing the room’s furniture, appliances, and baseboards. Remove everything moveable, so you get a good finish. Once the room is empty, clean the floor and remove dust. For best results, sweep first and then vacuum. The clean surface is ready for priming. 

Fill any cracks 

Use a filler and a sealer to fill the larger cracks in the concrete floor. To do this, place the nozzle of the filler bottle in the cracks and squeeze out enough filler to fill the crack. You can also press the filler into the cracks to ensure they are adequately filled. 

Ensure you have filled all the cracks before proceeding to the next step to avoid wasting the leveler. Allow the filler and sealer to dry, and then prime the surface.  

Apply primer

Once all cracks have been filled, use a soft-bristle push broom to apply and spread the primer. Use downward pressure to spread the primer thoroughly, ensuring you push it into the pores of the concrete. Allow the primer to dry for 3-24 hours. 

Mix the concrete

Pour the leveling compound into a bucket and add some water. Use a mixing paddle to mix it until you have achieved the right consistency. Work fast and mix one bag at a time because the compound dries fast.

Since you only have a 10-20 minute window before the compound begins to harden, you should work with a partner. An extra pair of hands is great because one person can mix the compound while the other installs it. 

Leave to dry 

Once the compound is installed, let it dry according to the instructions on the bad. Self-leveling concrete typically takes 4-24 hours to dry, so you should be able to walk on it after 4 hours. Give it at least 24 hours to dry completely before installing any other flooring. 

Summary 

Self-leveling concrete is a polymer-modified cement used to create high-compressive smooth flat surfaces. It is an ideal alternative to regular concrete because it is easy to use and fixes uneven floors in just 4-24 hours. 

Ideal for DIY projects, self-leveling concrete should only be used when there is no structural damage to the existing concrete floor. It is suitable for use on wood, tiles, and concrete. 

Self-leveling concrete is best for relatively small spaces because it is expensive compared to cement covering square footage at a much lower cost. Ultimately, self-leveling concrete offers a quick and easy fix for uneven floors.

How to Ensure a Successful Self-Leveling Underlayment Application | TEC

“Self-leveling underlayment” (SLU) is a bit of a misnomer. Although this type of product is incredibly useful, it does require a thoughtful installer to ensure the best results. Follow these guidelines to prevent issues in your self-leveling underlayment installation.

Select a product appropriate for the installation: Know your installation environment and familiarize yourself with the relevant ASTM standards for strength. A commercial floor subject to heavy rolling loads will require a higher-grade self-leveling underlayment (like TEC^® Level Set 300 Self-Leveling Underlayment) than a floor in a single-family home.

Also, it is critical to understand your project timeline and choose a product that fits within the appropriate schedule. Some products may require 24-48 hours prior to installing floor coverings while other more premium products are ready to accept moisture-sensitive floor covering in 12 to 16 hours.

Consult product data sheets for information on tensile strength, compressive strength and flexural strength, as well as recommended cure times.

Generally speaking, there are two types of self-leveling underlayments – traditional and next generation technologies. The most noticeable difference between traditional and next generation SLUs are the flowability and the smooth surface profile of each product. Check out TEC’s new high-flow SLU: Level Set 500 HF and for best practice tips for successful high flow SLU installations view our Technical Bulletin. 

Some installers prefer the attributes of traditional SLUs because of the working properties. Others prefer the new technology for its high flow properties and extended working time.

The job scope will dictate which product technology should be used for installation. Traditional SLUs work best for deep fill applications greater than 3/16”. The newer technologies are ideal for thinner applications.

Know your substrate: Most SLUs require that all surfaces are fully stable and structurally sound prior to the application of a self-leveling underlayment. For example, understanding your existing substrate porosity is critical to choosing the proper primer. (A simple water droplet test will determine the surface porosity per ASTM F3191). Equally important is to know the make-up of the existing substrate. For example: typically, sound concrete requires a single coat of primer. Unsealed Gypcrete may require additional steps, including multiple coats of primer prior to the application of cement-based self-leveling underlayment.

Prepare your substrate: Make sure to plug all floor openings, gaps and cracks and install termination dams to prevent any seepage. Consult with product manufacturers to determine moisture limitations of the floor covering, self-leveler, and adhesives to determine if moisture mitigation is needed.

If moisture mitigation is required, this must be done prior to installation of the self-leveling underlayment.

Self-leveling underlayments require the use of a primer prior to installation (like the TEC Multipurpose Primer). Failure to use product recommended primer may result in installation failure.  Primer retains the moisture within the self-leveling underlayment to allow proper curing. Secondarily, it acts as a bonding agent to ensure the SLU bonds properly to the substrate. Refer to the primer label for information regarding application methods and dilution per ASTM F3191.

Beyond priming, most self-leveling underlayments require that the substrate is free from any contaminants that may inhibit bond, including adhesive residue, sealers/curing compounds, oil, grease, loose or peeling paint, or other contaminants. Polished underlayments will require epoxy primers and/or a specific Concrete Surface Profile (CSP), and in these cases, mechanical abrasion (shot-blasting), is required.

Proper water demand: Mix your self-leveling underlayment within the water range specified on the bag. Overwatering will lower the strength of the underlayment and may cause cracking and disbonding. Additionally, a white film may form on the surface of the cured underlayment if the product is overwatered. Failure to properly mix the SLU may make it difficult to work with and lead to improper flow, cracking, or an irregular surface. Mix a minimum of two bags at a time when barrel mixing to ensure optimum efficiencies during the application process. In addition, some SLUs can be pumped. If pumping, special attention is needed to maintain proper water ratios and prevent overwatering. Follow equipment and product manufacturer’s recommendations when pumping self-leveler.

Product and ambient temperature: Make sure that the temperature of the room is within the manufacturer’s acceptable range. A climate that is too cold or too hot can affect the product, such as increased set time in cool temperatures or reduction in heal time in hot environments. Temperature and humidity will affect flow, working time and set time of the SLU.

Additionally, the temperature of the powder and the water is crucial. Leaving product in the sun, or in a hot environment may lead to flash setting. In situations where warm product is unavoidable, mixing with cold water may help combat installation issues. To maintain cold water temperatures in hot conditions, use blocked or bagged ice in your water barrel.

Whether the environment is warm or cool, acclimating the product prior to mixing is always a best practice.

Use as recommended: Manufacturers will specify the maximum thickness of their product. Some products allow for the addition of aggregate (pea gravel) to increase the depth of the pour, while others only allow their product to be used neat. Be sure to use the appropriate aggregate size and amount when extending a self-leveling underlayment in a single pour. Two separate pours or multiple lifts will achieve the target thickness without the use of additional aggregate. Once the SLU from the first pour becomes a walkable surface, you may proceed to apply the proper primer coat for the additional pour or lift. If a surface is extremely uneven in isolated areas with depressions greater than ½” deep (bird bath), you may treat these areas independent to the final pour. This will assist with the application process by using a consistent amount of self-leveling underlayment throughout the application. Always consult with manufacturers to determine the most suitable product for your application.

Protect your freshly poured underlayment: All self-leveling underlayments should be protected from direct air movement (drafts) during the initial curing process (2-6 hours) as they may cure prematurely which leads to cracking. Generally, most underlayments are not considered final wear layer surfaces. During the final curing process (2-24 hours) they should be protected from excessive construction. Traffic without protection can lead to gouging and irregular surfaces. Allow to cure completely to prevent any unnecessary surface damage, prior to the floor covering installation.

A common theme connects these successful self-leveling underlayment application guidelines: noting and adhering to the manufacturer’s instructions. You must read labels and product data sheets carefully to ensure products perform as desired.

Make sure to check out our entire line of Surface Preparation products. If you need assistance determining which product is right for your job, contact our Technical Support team here or by calling 1-800-832-9023, Mon-Fri 8 a.m. –  6 p.m. CST.

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Do-it-yourself self-leveling floor – step-by-step instructions on how to pour self-leveling floor

There is an opinion among the people that the floor is half the repair. It is not surprising that most people approach the choice of flooring with special responsibility. And the assortment here is very large – linoleum, laminate, parquet, tile, stone, carpet. However, it should be noted that these topcoats should only be laid on a perfectly flat surface. One of the modern ways to create a smooth, durable, wear-resistant base is a self-leveling floor.

A self-leveling floor with a balanced composition spreads easily over the surface, and after hardening forms a smooth base. He brilliantly copes with the task of smoothing out irregularities and eliminating differences.

Self-leveling floor is used both in residential premises and in public (shopping centers, office complexes) and industrial facilities (workshops, warehouses).

Advantages of self-leveling floors

• Durability. Coatings are highly resistant to cracking and do not shrink. The floor withstands temperatures from -50°C to +70°C.
• Economic consumption. For 1 m ² you need 13.5 kg of dry mix.
• Fast curing. Walking on the surface is possible after 4-6 hours.
• Environmentally friendly. Mixtures of the Starateli trademark correspond to GOST and can be used in residential premises.
• Ease of use. The balanced composition of the mixtures provides high-quality self-spreading and self-levelling.

Types and features of the material

Materials are classified according to different criteria, but primarily according to the binder. The most popular are coatings based on gypsum-cement (complex-mineral) binder. They do not require reinforcement. It is possible to lay the topcoat on them after 3-7 days (tile, stone) or after 7 days (laminate, linoleum). You will be able to walk on the surface already 4-6 hours after pouring.

Demanded cement-based compounds with the addition of fractionated sand and modifying additives. Such compositions are easy to work with. They dry to a smooth surface, can be walked on in 24 hours, and topcoat can be applied in 3-7 days.

The Starateli trademark produces self-leveling floors that comply with GOST 31358:

1 2 3

4 5

1. Thick (based on cement). Used for significant floor level differences. The recommended layer thickness is from 30 to 100 mm. Suitable for basic and final leveling of concrete or cement bases in rooms with normal and high humidity (including without heating). Can be used for outdoor work.
2. High strength (cement based). It is used in places with high traffic, where there are increased operational loads (garages, basements, industrial workshops, warehouses). Suitable for underfloor heating systems. Layer thickness – from 30 to 100 mm.
3. Practical (mineral binder based on gypsum and cement). This is the most popular material that is suitable for rooms with normal humidity in any building – from residential buildings, clinics and kindergartens to sports complexes, administrative facilities, industrial enterprises. Layer thickness – from 5 to 70 mm.
4. Fast setting (mineral binder based on gypsum and cement). The optimal solution in the conditions of tight deadlines: you can walk on such a surface after 4 hours. Suitable for all buildings – from residential buildings and schools to industrial workshops. Layer thickness – from 5 to 100 mm.
5. Thin (mineral binder based on gypsum and cement). It is used for final leveling of gypsum, concrete, cement-sand and other bases. Layer thickness – from 1 to 30 mm.

Benefits of the listed formulations:

• Perfectly smooth, even surface.
• Excellent spreadability.
• Strength, wear resistance.
• Resistant to moisture, cracking.
• Frost resistant.
• Reasonable price.

Tools used

For work you will need:

• Building tank 40 l. The mixture is kneaded in it. Its volume is enough to mix a bag of composition for 20–25 kg.
• Construction mixer or electric drill with special mixing attachment. Allows you to get a homogeneous mass.
• Needle roller. Used for rolling, leveling the mixture, removing air bubbles from it. It is supplied with a telescopic handle (provides for length adjustment).
• Studded shoe covers (plastic wet shoes). These are platforms with 2.5 cm long metal spikes that allow you to walk on wet floors without leaving marks.
• Building level (2-2.5 meters). It helps to calculate the required amount of the mixture, to control the quality of the filling after the composition has hardened. A spread of less than 2 mm per 2 m is considered normal.

How to pour a self-leveling floor with your own hands: step-by-step instructions

To get a perfectly even, reliable coating, you need:

1) Clean the base

It is convenient to remove dust and debris with an industrial vacuum cleaner. Do not forget to go around the corners with a vacuum cleaner pipe without a nozzle – this will effectively clean all hard-to-reach places. It is also necessary to get rid of oil stains and residues of other substances (for example, varnish or paint) that reduce adhesion.

All seams, holes and cracks must be sealed in the base to prevent leakage of mortar. For this, a thick cement-sand mortar is suitable.

2) Prime the surface

Applying a primer improves the adhesion of the substrate to the screed. To do this, it is most convenient to use a roller on a long telescopic handle. You can also work with a brush or spray gun.

For priming, the Prospectors brand primer (Profi, Universal, Deep Penetration) is suitable. It dries quickly and is economical. The composition can be applied in a wide temperature range – from +5 to +30 ◦С.

Please note that if the substrate is highly absorbent, it must be primed at least 2 times.

3) Determine the fill level

This task will help solve the level (for example, laser), thanks to which the horizontal is built. Using a reference pin beacon, the level of the future self-leveling floor is set in such a way that the highest point of the base (for example, a ledge or mound) is covered by the minimum layer (this information is provided on the packaging of the self-leveling floor). For example, for floors “Practical” and “Quick hardening” the minimum layer is 5 mm. Further, other beacons-beacons are placed on the same level with the first beacon over the entire area of ​​​​the room. To do this, an equal distance is measured from each lighthouse along the already constructed horizontal. Thus, the lower limb of each beacon pin is on the same plane – this is the level to which the floors will be poured.

Also don’t forget to glue the damper tape around the perimeter of the room at the base of the wall, around protruding elements (eg columns). It is needed to compensate for linear deformations and with temperature jumps.

4) Prepare the solution

The proportions indicated on the packaging of the mixture must be strictly observed. Pour a bag of dry mixture into a container with clean water. Please note that an overdose of water may reduce the strength and delamination of the coating. Then the composition is mixed until a homogeneous viscous mass is formed. The mixture is left for 5 minutes, then stirred again. It must be used within 40 minutes.

5) Pouring the floor

It is convenient to pour the floor in special nozzles with spikes (they are called wet shoes). Work begins with the areas most distant from the entrance.

Remove the air from the mixture with a needle roller (you can also use a T-bar). You can walk on the flooded surface after the period of time indicated on the package. For example, for quick-hardening compounds it is 4 hours, for thick self-leveling floors – 24 hours.

To check how smooth the finished surface is, the bubble level will help: the bubble should be exactly in the middle.

You can study the detailed characteristics of self-leveling floors of the Starateli trademark on the company’s website. Here you will find detailed video instructions for pouring the floor.

BROZEX LEVEL FINAL NF420: Cement based self-levelling finish

Good afternoon. As I understand it, this mixture can be used for the subfloor, laid directly on the floor slabs? And then use floor levelers on top of it at the finish, before laying the laminate?

Hello!

For the base layer of the screed, we recommend using a screed with reinforcing fibers Brozex Armika NF45. The finishing layer before laying laminate flooring is easy to make with the self-levelling and fast setting compound Brozex Level Final NF420.

Watch the master class on laying the screed and finishing floor on our youtube channel.

Thank you for your interest in our products.

Hello. I need to level an unsuccessfully filled floor with gypsum levelers. Can I use the LEVELER FINAL NF420 for this purpose.

Good afternoon. If it is necessary to eliminate surface irregularities, BROZEX NF420 LEVELING FINAL is ideal, but it must be taken into account that the base must be solid, dry, thoroughly cleaned of dust, old paint, grease and oil stains; fragile and flaking areas removed; cracks, potholes and depressions are eliminated. The recommended application thickness is 3-20 mm.

Hello, Brozex NP-42 self-leveling floor series, is this nf420?

Good afternoon. The new name of BROZEX NP-42 LIQUID FLOOR – BROZEX NF420 LEVELING FINAL.

Hello, tell me, after pouring a self-leveling floor, for example, NF 420, should it be covered with a film the next day or should it dry under normal conditions. Do you have any recommendations? Thank you

Good afternoon, it is not necessary to cover the BROZEX NF420 LEVELER FINAL during the hardening process. When carrying out work and during the hardening period, it is necessary to avoid drafts, prevent direct sunlight from reaching the surface, observe the temperature and humidity conditions in the room (the temperature in the room and the surfaces to be finished is from 5 to 30 ° C, relative air humidity is not more than 60%).

It is possible to work with the nf420 level using beacon rails as a rule. And is it allowed to add fiber and what length.

Good afternoon.
1. The procedure for pouring the self-leveling floor BROZEX NF420 LEVELING FINAL: evenly pour the base sections, starting from the lowest point, along special beacons-benchmarks to the required thickness. Avoid technological breaks in the process of work. Immediately after pouring, roll the layer with a spiked roller (do not level with a rule, as the mixture is self-leveling) to remove air bubbles to obtain a smoother surface.
2. Additional input of components into mixtures is not recommended, as it will lead to a change in the properties of the product, which does not guarantee a positive result.

Can the self-leveling floor be poured with the underfloor heating switched on? Just winter, and this is the only type of heating in the house

Hello!

Thank you for your interest in BROZEX Dry Mix products.

It is recommended to install a self-leveling floor at a base and ambient temperature of +5…+30ºC (3 days before and after pouring). In your situation, we recommend pouring the self-leveling floor during a favorable climatic period, when floor heating is not required, its possible inclusion no earlier than 7 days after pouring.

Hello, can BROZEX GYPSUM LEVEL NF450 be used to level the floor in the bathroom and toilet? If not, which of your products can be used in this case?

Hello!

Thank you for your interest in BROZEX DRY MIX products.

BROZEX GYPSUM LEVEL NF450 is designed for finishing leveling of the base in rooms with a relative humidity of not more than 60% and is not suitable for use in bathrooms and toilets. For floor installation in wet rooms with subsequent tiling with ceramic tiles, we recommend using cement-based mixtures: BROZEX NF410 LEVELER START, BROZEX NF40 SCREED, BROZEX NF45 ARMIKA; mixtures for the final leveling of the floor base: BROZEX NF420 LEVELER FINAL, BROZEX NF415 LEVELER MEDIUM subject to the following conditions: the application thickness of one layer is at least 10 mm, when the final layer is completely dry, its subsequent treatment with polymer-based waterproofing compounds.

Hello, 150 m2 screed is to be poured onto floor slabs. What is the minimum layer allowed screed nf40. As written on the package 1 cm. Will it crack in the future? Thank you

Hello! Thank you for your attention to our products. Brozex SCREED NF40 is used for the initial leveling of floor bases with a layer thickness of 10-80 mm, if the instructions indicated on the package are followed, cracking of the screed will not occur. .

Can the concrete surface be primed with concrete contact before pouring with BROZEX NF-420 self-leveling floor?

Hello!

We recommend using a primer suitable for your substrate type. Concrete-contact primer is used for the treatment of bases made of monolithic or precast concrete, that is, smooth and non-absorbent bases. In the case when it comes to finishing the leveling of the rough screed, we recommend using a universal acrylic primer.

We recommend watching a video with a master class on the use of BROZEX NF-420 self-levelling quick-hardening mortar on our youtube channel.

Thank you for your interest in our products.

How to calculate the consumption per 12 sq.m.?

Hello!
Consumption of dry mix BROZEX LEVEL FINAL NF420 at a layer thickness of 1 mm from 1.6 kg/sq.m. On our youtube channel, the master practitioner tells in detail how to calculate and apply a self-levelling floor leveler, shares the features of working with the mixture and life hacks. Thank you for your interest in our company’s products.

Hello guys, for 1.5 sq.m on the floor with a layer of 3 cm, how many bags do you need and do you need to put damper tape on the wall?

Hello! Self-levelling BROZEX NF420 LEVELER FINAL is allowed to apply a finishing leveling layer with a thickness of not more than 20 mm. We recommend using BROZEX LEVELER MEDIUM NF415 self-levelling compound to level the floor with a layer thickness of 30 mm. Damper tape must be used. To level an area of ​​1.5 sq.m, you will need 4 bags of BROZEX LEVELER MEDIUM NF415 floor leveler. Thank you for your attention to BROZEX products.

Hello. Filled the first layer 10mm. We plan to pour over the second layer of 3 mm. Are there any concerns that it may crack? Could you tell me the second layer can be poured? If yes, after what period of time?

Hello! The minimum layer thickness of BROZEX NF450 Self-Leveling Floor Leveler Level Medium is 5 mm. To create the second layer, we recommend using BROZEX NF420 Leveling Final, which should be applied after the first layer has completely dried and cured (depending on the degree of drying of the initial layer). Filling is allowed no earlier than after 7 days, while controlling the residual moisture content of the base. Before applying the second layer, it is necessary to dedust and prime the base.
On our youtube-channel you can get acquainted with the order of work performed by the composition of BROZEX Level Final from a practitioner. Thank you for choosing our products.

After leveling nf 420 I will lay linoleum, can I prime the self-leveling floor and is it necessary?

Alexander, good afternoon! Thank you for your interest in BROYEX DRY MIX products. Surface priming when using a mixture of LEVELER FINAL NF420 is necessary only when preparing the base before applying the mortar mixture. Prior to laying linoleum as a top coat, no surface priming is required unless recommended by the manufacturer of the linoleum or other top coat. In this case, the coating manufacturer’s recommendations should be followed.

How to calculate the number of bags to fill the floor??

Alexander, good afternoon! Thank you for your interest in BROZEX DRY MIX products. Consumption of dry mixture LEVELER FINAL NF420 16-17 kg per 1m2 with a layer thickness of 10mm.

Hello! Level final 420, in the instructions the layer thickness is up to 20 mm, can it be exceeded by 5 mm?

Andrey, good afternoon! Good afternoon Thank you for your interest in BROZEX DRY MIX products. We do not recommend increasing the thickness of the layer, as in this case we cannot guarantee a high-quality, durable base. If you need a layer of 25mm, we recommend using the LEVELER MEDIUM NF415 for work.