What is Rock-Tite?

Introducing Rock-Tite, a 3-step system for laying outdoor 20mm porcelain tiles.

This simple to use step by step system is DIY friendly, to make it even easier we’ve created a simple how to video to follow but you can also read through more detailed instructions below.

1. Rock-Tite Porcelain Primer

The porcelain primer is a high strength bonding agent that you apply directly to the back of the tile to help it adhere to the mortar bed you are placing the tile on to.

It’s polymer modified and fibre reinforced and just needs mixing with water.

2. Rock-Tite Mortar

The mortar is ready to use, it just needs water adding to it, offering a fibre reinforced formula with built-in plasticisers.

2a. Rock-Tite Mortar Additive

If you are tiling a larger area then step 2a is needed, an additive for the mortar. This should be mixed with sand and water.

3. Rock-Tite Brush-In Grout

The brush-in grout fills in the gaps between your tiles. This formula is strong, flexible and long lasting whilst being permeable (allowing water to run through it). It’s suitable for smaller grout joints (from as little as 3mm wide).

3a. Rock-Tite Flow Grout

The brush-in grout alternative is the non-permeable formula known as Flow Grout, which is rapid setting and super smooth, ideal for larger joints (up to 25mm).

How to prepare your area

Firstly, you’ll need to build the hardcore substrate. Dig out the area to be tiled (making sure it’s stable) to a minimum depth of 45mm below the planned patio surface. This allows for a 25mm mortar bed and 20mm for the tiles on top. For porcelain tiles, you’ll need 100mm-150mm of compacted hardcore.

You’ll then need to create a fall so water can off, away from your home, safely. The area should fall away from any property at a ratio of 25mm over a 1.5m length.

You’re then ready to add your Compact Type 1 or MOT grade hardcore, making sure it’s rigid and stable. You can hire a wacker plate to compact the hardcore.

Remember, the ground beneath must be free-draining and the sub-base permeable to allow water to escape.

Preparing your mortar

The next step is to ready your mortar. You’ll need a mechanical mixer to mix the Rock-Tite Mortar at a ratio of 3Ls water to 20KG powder. Remember only to mix enough to be used within the 60-minute pot life otherwise you’ll waste product.

If you’re adding in the additive (Part 2A) then you’ll need to blend a full 15KG bag or mortar additive with 90KG of sharp sand (a 1:6 mix) in a mechanical mixer. You’ll then need to add a sufficient amount of water to blend the mix until it’s smooth and lump-free.

Prepping your primer

Now we need to prime the tiles for laying. Start to prepare Part 1 (the porcelain primer) by pouring water into the graduated mixing bucket to the required level and then gradually adding the required amount of primer powder. It’s approximately 1.6L of water for every 5KG of powder.

Continue mixing until it forms a smooth, lump-free slurry. Similar to the mortar, only mix enough to be used within the 60-minute pot life to avoid wasting product.

Laying your tiles

Once both primer and mortar are mixed, start by adding the slurry primer onto the back of your tiles with a brush or roller to ensure it’s evenly covered in a thin layer. You’ll need to move fairly quickly as the primer must still be wet when laying it into the mortar.

Then, lay a solid bed of mortar on top of the compacted hardcore. It needs to be at least 25mm deep if you have a 100mm deep or more hardcore layer.

When laying the tiles, leave at least 3mm between each tile to create a joint width. Using a rubber mallet, make sure each tile is level and properly bedded into the mortar.

Once you’re finished, allow it to dry for 24 hours before you begin grouting it.

Grouting your patio – Brush-In Grout

Make sure the joints are clean and dust free and then wet the surface of the tiles, ensuring to keep them moist throughout the grouting process.

Begin to brush in the grout at a 45-degree angle using a long-handled brush. Keep going until all the joints are filled and void free (keeping the surface wet as you work).

If you have excess grout, simply put it back in the tub and ensure it’s covered with 50mm of water above the grout surface.

To finish the patio, compact the joints, finishing them with a jointing tool. You can use a gloved finger depending on the joint width, but a smoother, more professional finish will be easier with the correct tool. If any voids appear whilst smoothing, just rewet the surface, refill and refinish and brush off any excess grout. Then, all you have to do is leave it for 24 hours to cure.

Grouting your patio – Flow-Grout

For the flow grout, the joints will need to clean and dust free and your tiles kept wet throughout the grouting process.

Add 1L of clean water per 5KG sachet into the bucket, slowly adding the powder to the water and then mechanically mix it for 3-5 minutes. It needs to be smooth and lump-free but ensure not to overmix it as it will allow too much air into the formula.

This formula only has a working time of 10 minutes so ensure you don’t mix too much in one go to avoid product wastage.

When the product is mixed and your tiles are wet, pour and spread the flow grout into the tiles using a rubber squeegee or grout float. Continue to move the excess around, topping it up as needed until every joint is filled.

Depending on site conditions, it will take 1-2 hours to reach an initial set. This means it have hardened enough for the tiled surface to be cleaned, you’ll need to use a wet brush or sponge, taking care on the freshly applied joints. Cleaning of the tiles must be done thoroughly to ensure no mortar is left on the tile surface.

You can then walk on the finished patio after 3 hours.