The DIY application of screed can be carried out relatively easily by following simple steps. You need to get some supplies, and you are good to go. However, it should be remembered that there will always be a difference between the quality of DIY applications and those carried out by professionals.
Step 1: Get Supplies and Tools
You can get these supplies from your local hardware store.
- Self-Levelling Compound
- Mixing Paddle and Drill
- Spirit Level
- Trowel
- Bucket
- Protective Gloves and Eyewear
- Notched Trowel (Optional)
- Primer (if Recommended by the Manufacturer)
Step 2: Site Preparation
Before screeding a floor, prepare the surface to ensure it is clean, dry, and level. For site preparation and cleaning, you will need the following supplies:
- Broom and Dustpan
- Vacuum Cleaner
- Scraper or Chisel
- Hammer
- Cleaning Solution (Such as Soap and Water or Degreaser)
- Bucket
- Sponge or Scrub Brush
- Spirit Level
- Sandpaper or Grinding Tool
Site Preparation Steps
- Remove any existing flooring material, such as tiles or carpet, using a scraper, chisel, and hammer.
- Sweep the floor surface thoroughly with a broom and dustpan to remove any loose debris or dust.
- Vacuum the floor surface to remove any remaining dust or debris.
- Use a scraper or chisel to remove adhesive, glue, or other stubborn materials from the floor surface.
- Clean the floor surface with a cleaning solution, such as a degreaser or soap and water, to remove dirt or stains. Rinse with clean water and allow the surface to dry entirely.
- Check the levelness of the floor surface using a spirit level. If there are any low spots or high spots, mark them for later adjustment.
- Use a sandpaper or grinding tool to smooth out any rough spots or high spots on the floor surface. This will help to ensure that the self-levelling compound will adhere properly.
- Once the floor surface is clean, dry, and level, you can proceed with screeding.
Step 3: Screed Application Process
Once the floor has been prepared and cleaned, you can move to the screed application. The first step in screed application is screed mixing. Mixing screed for application is crucial in ensuring a smooth and level finish. Here are the general steps for mixing screed:
- Gather Materials: You will need a screed mix, water, a mixing container, a mixing drill or paddle, and a straight edge.
- Measure Materials: Measure the amount of screed mix and water required for the job. The water-to-screed mix ratio will vary depending on the manufacturer’s instructions, so follow the guidelines carefully.
- Mix the Screed: Pour the screed mix into the mixing container and gradually add the water, mixing as you go. Use a mixing drill or paddle to ensure the mixture is smooth and free from lumps. The consistency of the mixture should be similar to a thick porridge.
- Check Consistency: Once the screed mix and water are thoroughly mixed, check the consistency of the mixture. It should be easy to spread but not so thin that it runs or drips.
- Let the Mixture Sit: Allow the screed mixture to sit for a few minutes before using it to allow the mix to settle.
- Mix Again: After letting the mixture sit, give it one final mix to ensure it is smooth and free from lumps.
Step 4: Pouring the Screed
Pouring and applying screed is a process that requires careful attention to detail to ensure a smooth and level finish. Follow the simple steps below to ensure perfect application.
- Plan the Pour: Plan the pour, considering the shape and size of the area to be covered. Divide the area into sections to make the application process more manageable.
- Pour the Screed: Pour the screed mixture onto the surface in manageable sections. Use a straight edge to spread the screed evenly and ensure it is level. It is essential to work quickly during this process to avoid the screed setting before it can be distributed evenly.
- Spread the Screed: Spread the screed mixture evenly using a straight edge. Move the straight edge back and forth in a sawing motion to level the screed. Ensure that the surface is smooth and level throughout.
- Check the Level: Use a spirit level to check the level of the screed. Make any necessary adjustments to ensure that the surface is level.
- Smooth the Surface: Once the screed is level, use a spiked roller to smooth the surface and remove air pockets. This will ensure that the screed sets evenly.
Step 5: Curing the Screed
After the screed has been applied, it must be properly cured to ensure it sets evenly and achieves its maximum strength. Here are some general guidelines for screed curing:
- Allow the Screed to Dry: Once it has been applied, it needs to be allowed to dry before any foot traffic or heavy objects are placed on it. This can take anywhere from 24 to 48 hours, depending on the type of screed and the thickness of the application.
- Control the Temperature: During the drying process, it’s essential to control the temperature and humidity levels to ensure that the screed sets evenly. Keep the room at a moderate temperature and avoid exposing the screed to direct sunlight or extreme temperature changes.
- Gradually Increase the Temperature: Once the screed has dried, gradually increase the room’s temperature over several days. This will help to prevent cracking and ensure that the screed sets evenly.
- Protect the Surface: During the curing process, it’s essential to protect the surface of the screed from damage. Avoid walking on the screed or placing heavy objects on it until fully cured.
- Moisture Testing: Before applying any floor covering, it’s crucial to test the moisture level of the screed to ensure that it is fully cured. Moisture can cause damage to floor coverings and can also impact the durability of the screed itself.
Following the manufacturer’s instructions for screed curing is important, as different types may require different curing times and techniques. If you need help with how to cure your screed properly, it’s recommended to seek the advice of a professional screed contractor.
Step 6: Sanding and Finishing
Sanding and finishing the screed is an important step in achieving a smooth and level surface for installing flooring or other finishes. Here are some general steps for sanding and finishing the screed:
- Check the Level: Before sanding, check the level of the screed with a spirit level. Sand down any high spots or bumps to create a smooth and level surface.
- Use the Right Sandpaper: Choose the appropriate sandpaper for your screed, typically a medium to coarse grit sandpaper. It’s important to avoid using fine-grit sandpaper as this can clog and damage the sandpaper.
- Sand the Surface: Sand the surface of the screed using a floor sander or hand-held sander. Work in small sections, moving back and forth until the surface is smooth and level.
- Clean the Surface: Once the sanding is complete, clean the surface of the screed thoroughly to remove any dust or debris.
- Apply a Finishing Coat: Apply a finishing coat to the screed to protect it from damage and improve its durability. The type of finishing coat will depend on the type of screed and the intended use of the surface. Standard finishing coats include epoxy resin or polyurethane.
- Allow the Finishing Coat to Dry: Allow the finishing coat to dry according to the manufacturer’s instructions before installing flooring or other finishes.
Frequently Asked Questions About Screed Application:
How Thick Should the Screed Be?
The thickness of the screed will depend on various factors, such as the type of flooring being installed and the subfloor’s condition. Typically, the screed should be between 25-50mm in thickness.
Can Screed Be Used with Underfloor Heating?
Yes, screed is commonly used with underfloor heating systems. Liquid screed is often preferred for this purpose, as it can be applied at a thinner depth and has good thermal conductivity.
Can Screed Be Used for External Applications?
Screed can be used for external applications, such as patios and walkways. However, it is essential to choose a screed suitable for outdoor use and withstand exposure to the elements.
Can Screed Be Laid on a Timber Subfloor?
Yes, screed can be laid on a timber subfloor, but it is essential to use a suitable underlayment or insulation layer to prevent moisture from damaging the timber.
Can the Screed Be Painted or Coated?
Yes, screeds can be painted or coated with various materials, such as epoxy, polyurethane, or acrylic. However, preparing the surface properly before applying any coating is crucial.
How Long Does the Screed Last?
Screed can last for many years if properly installed and maintained. However, its lifespan will depend on various factors, such as the quality of the materials used, the thickness of the layer, and the level of foot traffic and wear and tear.