How To Apply Cement Render to Wall?
In this article, we’ve prepared a guide on how to apply cement render to a wall as a DIY project. Essentially, rendering brick walls with cement tends to be quite challenging.
Although cement render is a traditional rendering technique, it has proven to be highly efficient.
While it might seem to be a challenging project, it’s a recommendable rendering method, especially for anyone who wants to coat their block or brick walls with a durable render finish.
However, it’s worth noting that you can only apply cement render on masonry walls. You can’t apply cement on drywall. Ensure you read and follow each step carefully for the best results.
Before starting, you’ll need to get the cement mix ready. Preferably, use premixed cement render.
You’ll only need to add water and sand to the premixed cement. Premixed cement render is advantageous in that it contains additives that allow for better results upon application.
Alternatively, you can prepare the cement mix yourself by mixing cement, sand, water, and lime. Check the instructions on the cement bag on how to mix it properly. Generally, you should mix 1 part cement with 2.5 or 3 parts fine sand.
You can also use the traditional method of preparing cement render by mixing 1 part cement, 6 parts fine sand, and 1 part lime. Preferably, use a concrete mixer to get the right mix.
When using the mixer, first, add cement, sand, and lime. Then add water. Ensure the compounds mix for not less than 5 minutes. They should mix to form a consistency similar to that of pinnate butter.
- Cement render
- Fine sand
- Spirit level
- Carpentry pencil
- Measuring tape
- Eye protection
- Safety gloves
- Margin trowel (for spreading cement)
- Concrete mixer (for mixing cement)
- Wheelbarrow or construction buckets (for transporting cement)
- Use a well-prepared cement mix
- Ensure the structural pillars on the walls are plumb
- 1 day per 30 square feet
Steps to Follow
Before applying cement to wall, ensure you check the wall for certain aspects. For instance, you need to ensure the wall is plumb. They shouldn’t have irregularities.
If you’re rendering old brick walls, start with removing any coats covering the bricks. You can use a hammer, palette knife, and chisel to remove the coats.
Upon removing the old coat, brush the walls thoroughly. Ensure there’re no coating residuals left. Also, there shouldn’t be dust on the wall.
Next, apply fungicide over the wall. Although you may skip this step, it’s recommended to do it for older houses.
Next, apply the first coat of the cement mix. Before applying cement, ensure you remove or cover any items around the area you’re working on to avoid staining them with the cement render.
The role of the first cement coat is to stick to the bricks and offer support for the second coat and plaster.
Ensure the first cement coat is mixed in a ratio of 1 part cement and 2.5 or 3 parts fine sand. Also, check the instructions on the cement bag for proper mixing. Put the sand and cement into the mixer. Then add water until the mixture forms a consistency similar to that of cream.
Before applying the second cement coat, you’ll need to construct guidance pillars standing vertically after every 3 feet, 90cm. While building the pillars, start with building two bumps on the wall.
One of the bumps should be located at the foot of the brick wall whereas the other should be on the top.
The bumps should have a thickness similar to that of the cement render layer. Thus, ensure it’s about 0.5 inches thick. Also, the protrusions should be plumb to each other. Else, the wall won’t have the best look.
You can check whether the two bumps are vertical with the help of a spirit level and straight edge.
In case the top and bottom guidance points are not plumb, you’ll need to apply more cement render either on the top or the bottom of the brick wall. Ensure the thickness of the bump doesn’t exceed 0.5 inches.
Upon building the first guidance pillar, build other pillars every 3 feet, 90cm apart. Additionally, ensure all the guidance pillars are properly aligned with each other, especially if you’re dealing with a wall featuring poorly done bricklaying.
To construct the pillars, apply enough cement mixture over the wall, just between the top and bottom bumps. Use a straight edge to level each pillar.
Build another pillar as you did with the previous one. Next, apply the cement render between the bumps.
Continue repeating this step until the entire wall is rendered. Build the pillars and apply cement render carefully. Else, the result may not be that great.
Expert Tip: Allow the pillars to dry for some hours before applying the cement render. Also, allow the first cement coat to dry for a minimum of one day before building the pillars.
Apply a second coat of cement render between the pillars. Ensure you cover the entire surface between the pillars.
Extra Tip: Be careful when applying the cement. Work with utmost patience to ensure the render is even. If not, you’ll have more work to do to straighten out the wall.
If the render isn’t even, you’ll need to straighten it by pushing a straight edge over the wall while moving from the left side to the right side. Also, ensure you move the straight edge along the pillars. Use a margin trowel to remove the cement material from the straight edge and continue straightening the wall.
If the rendered surface is not uniform, give the render about 15 minutes to dry before any attempt to load it with more cement. Next, use a straight edge to smoothen the surface.
Allow the rendered wall to dry for about 1 hour. That way, the cement will bond well on the wall. Next, give the wall a good finish with the help of a polystyrene float.
Move the polystyrene float in a circular motion over the rendered surface to give it a smooth finish. You won’t find a lot of difficulties to give the render a great finish.
You can make it easier to finish the rendered surface by sprinkling water over the wall with a brush. However, excessive water may damage the wall. Thus, only sprinkle a little water.
Allow the rendered wall to dry for about 2 to 3 days. Once done, plaster the wall. Thereafter, paint the wall with a colour of your choice.
Ensure every cement coating is uniform across the entire wall. Else, you’ll spend extra money and time to add the finishing layers before painting. Thus, work with utmost care and patience when applying cement to wall for the best results.