Everything You Need to Know to Lay a Beautiful Terrazzo Floor

Why Laying Terrazzo Tiles Requires Expertise

You want a beautiful terrazzo floor that stays looking great for years. But anyone who looks into laying terrazzo tiles quickly realises: this is not ordinary tiling work.

Why are some tiles dark upon delivery? When can you apply sealant? Which adhesive is suitable? And what happens if the grout is applied too early or the wrong cleaner is used?

These are not minor details. With terrazzo tiles, incorrect storage, moisture, unsuitable adhesive, or aggressive cleaning products can cause stains, discolouration, or permanent damage. Precisely because terrazzo is a high-quality and characterful floor covering, mistakes should be avoided from the outset.

At Tegel BV, we have worked with terrazzo, natural-stone-like materials, and specialist tiling solutions for many years. From practical experience, we know what works well, but also where problems can arise. Not because people work carelessly, but because terrazzo demands special attention during storage, preparation, laying, grouting, sealing, and maintenance.

In this article, you will find out what to look out for when laying terrazzo tiles yourself or having them laid. After reading, you will have a better understanding of which questions to ask your tiler, which products are suitable, and how to avoid common problems.

What Is Terrazzo?

Terrazzo is a composite material made from aggregates such as marble, basalt, granite, or other types of stone. These small stones are combined with cement, pigments, and binding agents. The result is a robust, vibrant tile with a natural appearance.

Terrazzo has its origins in the region around Venice, Italy. Leftover material from stone processing was initially used as a practical floor and foundation solution. Over time, terrazzo developed into a fully-fledged artisanal floor covering.

Our terrazzo is still produced in the Veneto region. We call the collection Sassi, the Italian word for pebbles. The terrazzo is hydraulically pressed into large blocks. Such a block is approximately 3.10 metres long, 1.20 metres wide, and 80 centimetres high. The blocks are then first sawn into slabs, which are subsequently cut into tiles.

Why Terrazzo Tiles Are Sometimes Dark on Delivery

A common question is:

“My terrazzo tiles are dark or have dark patches. Are they damaged?”

In most cases, the answer is: no.

Terrazzo tiles are wet-sawn. As a result, moisture may still be present in the tile upon delivery. This moisture can sometimes cause temporarily dark patches. Once the moisture evaporates, the tile returns to its normal colour.

This is therefore generally not a production defect, but a temporary appearance. It does, however, require patience.

Important: Never seal damp terrazzo tiles. Always wait until the tiles are completely dry. This can take several days, but sometimes longer. Especially if the underlying concrete floor or the storage area is damp, the drying process may take more time.

How to Store Terrazzo Tiles Before Laying

Good storage may seem like a detail, but it is one of the most common causes of stains and discolouration. In particular, moisture that cannot escape properly can cause problems.

Always store terrazzo tiles:

In a dry location
In a well-ventilated room
With sufficient spacing so that moisture can escape
Protected from construction dust and dirt
Not airtight under plastic sheeting or cardboard

Are the tiles already on the floor while work is still ongoing? Cover them with a cotton or linen cloth. Do not use plastic, cardboard, or painter's film. Non-breathable materials trap moisture and can, for that very reason, cause stains.

When to Use Primer with Terrazzo Tiles

A primer is used before laying a tiled floor when the substrate requires it. The primer improves adhesion, regulates absorbency, and ensures that the tile adhesive can cure more evenly.

When laying terrazzo tiles, this is especially important, as terrazzo is heavy and requires a stable, full-surface bond. The substrate must not draw moisture from the adhesive too quickly, but should also not be too smooth or too dense.

Primer on Highly Absorbent Substrates

Use primer on highly absorbent substrates such as:

Cement screeds
Sand-cement floors
Anhydrite screeds
Gypsum-bonded screeds
Aerated concrete
Old porous levelling layers

A highly absorbent substrate draws moisture from the tile adhesive too quickly. This can cause the adhesive to dry too fast and adhere poorly. A primer slows this absorption.

A simple test: apply some water to the floor. Does the water absorb immediately? If so, the substrate is likely highly absorbent and a primer is usually required.

Primer on Smooth or Dense Substrates

Use a bonding primer or contact primer on smooth or dense substrates such as:

Existing tiled floors
Concrete with a dense surface
Smoothed concrete floors
Firmly adhered old adhesive residue

Here the primer provides additional grip between the substrate and the tile adhesive.

Important: A primer does not resolve a poor substrate. The floor must always be clean, dry, dust-free, grease-free, and stable.

As a primer, we recommend: Kiesel Octamus UG30.

Step by Step: Laying Terrazzo Tiles

A good terrazzo floor begins with inspection and preparation. Allow sufficient time for this. Mistakes that are visible before laying are often difficult or impossible to rectify after installation.

Step 1: Inspect the Tiles Before Laying

Check every tile before installation for:

Damage
Colour differences
Dimensional deviations
Visible defects
Damp patches or dark discolouration

Always do this before the tiles are laid. Once tiles have been installed, visible defects can generally no longer be assessed as a complaint. A good tiler therefore always checks in advance.

Do tiles need to be cut? Use a water-cooled saw. Small holes or irregularities can be carefully filled with grout later.

Step 2: Prepare the Substrate Carefully

The substrate largely determines the end result. A poor substrate can lead to loose tiles, cracks, moisture problems, or unevenly laid tiles.

The substrate must be: level, smooth, dry, dust-free, grease-free, and stable.

We recommend as a primer: Kiesel Octamus UG30. Apply it to a clean substrate and allow the primer to dry completely before continuing.

On average, allow approximately 150 grams of primer per square metre. This may vary depending on the substrate. When using the primer undiluted, one litre covers approximately 6 to 7 m². When in doubt, always consult your tiler.

Important: Never lay terrazzo tiles in a wet mortar or screed bed. Always use a tile adhesive suitable for natural-stone-like materials.

Step 3: Use the Correct Adhesive Technique

Prepare a good layout and setting-out plan in advance. This prevents narrow or illogical cut pieces at the end of the room.

Then work carefully:

Remove dust from the back of the tile with a damp cloth or sponge
Use Kiesel Servolight S1 Supertec as tile adhesive
Apply the adhesive on both sides — to the substrate and to the tile
Use a notched trowel with 10 to 12 mm notching
Allow approximately 5.5 to 7.5 kg of adhesive per m²
Remove adhesive and cement residue immediately with clean water
If needed, use Lithofin MN Fleckstop or Lithofin MN Stain Remover, depending on the application and manufacturer's recommendation

Also bear in mind the weight. A terrazzo tile in the 60 × 60 × 2 cm format weighs approximately 20 kg per piece. This makes installation physically demanding and technically less forgiving.

Step 4: Seal Before Grouting

This is one of the most important steps when laying terrazzo tiles.

Many people think that sealing should only be done after grouting. With terrazzo, this is risky. Because terrazzo is porous, cement and grout residue can penetrate the tile. This can cause permanent grey stains.

Therefore, apply a first coat of sealant before grouting. Use: Lithofin Fleckstop W.

Pay attention to the following:

The floor must be completely clean
The tiles must be completely dry
Dried adhesive or cement residue must first be carefully removed
Never use chlorine, vinegar-based cleaners, or acidic products
Apply the sealant with a paint roller or soft cloth
Allow the coat to dry for 12 to 24 hours

Acidic products can permanently damage the surface of terrazzo. Therefore only use products suitable for natural-stone-like materials.

Step 5: Grout the Terrazzo Tiles Carefully

For grouting, we recommend a joint width of 2 to 3 mm. Preferably use a mid-grey or silver-grey grout:

Application	Recommended Product
Mid-grey grout	Kiesel Servoperl Royal mid-grey
Silver-grey grout	Kiesel Servoperl Royal silver-grey

For tiles in the 60 × 60 × 2 cm format and a joint width of 2 to 3 mm, allow approximately 350 to 450 grams of grout material per m².

Remove excess grout immediately with a sponge and clean water. Then rinse the entire floor again. Once dry, any cement haze can be removed with Lithofin MN Cement Haze Remover.

Once the floor is completely clean and dry, apply a second coat of sealant. Remove any residue that is no longer absorbed immediately.

Wait at least two weeks before carrying out the first thorough cleaning.

Are Terrazzo Tiles Worth the Investment?

Terrazzo tiles often require a higher initial investment than many other floor coverings. However, a well-laid and well-maintained terrazzo floor is exceptionally long-lasting.

Many floor coverings need to be replaced after 10 to 15 years. A terrazzo floor, when professionally laid and maintained, can last significantly longer. This makes terrazzo an interesting choice for homes, shops, hospitality venues, hotels, and projects where appearance and longevity matter.

This is also why architects and designers are increasingly choosing terrazzo — not only for the look, but also for the combination of character, wear resistance, and long service life.

Recommended Products for Laying Terrazzo Tiles

Application	Recommended Product
Primer	Kiesel Octamus UG30
Tile adhesive	Kiesel Servolight S1 Supertec
Stain remover during installation	Lithofin MN Stain Remover
First and second sealing coat	Lithofin Fleckstop W
Grout	Kiesel Servoperl Royal silver-grey or mid-grey
Cement haze remover	Lithofin MN Cement Haze Remover

These products match the technical requirements of terrazzo tiles and help to prevent stains, adhesion problems, and damage.

Key Points When Laying Terrazzo Tiles

Dark tiles are often temporarily damp, not damaged
Never seal damp tiles
Do not use plastic, cardboard, or painter's film as a cover
Never lay terrazzo in wet mortar or screed
Use adhesives and cleaners suitable for natural stone
Always seal before and after grouting
Never use acidic cleaning products
Allow the floor to dry sufficiently before intensive cleaning

Anyone who takes these steps seriously greatly increases the chance of a floor that not only looks beautiful at handover, but remains beautiful for many years to come.

Conclusion: Laying Terrazzo Tiles Requires Preparation

A terrazzo floor can remain beautiful for many years, but only when storage, substrate, adhesive, grout, and sealant are well coordinated. The most important insight is simple: do not rush, allow moisture to evaporate sufficiently, and use products suitable for terrazzo.

Terrazzo is not a floor for hasty work. Calmness, control, and expertise determine the end result.

At Tegel BV, we help customers every day with the selection, installation, and maintenance of special tiles. From handmade tiles to terrazzo: we are convinced that good information in advance leads to better results later on.

Are you unsure whether your substrate is suitable, which adhesive to use, which grout is appropriate, or when to seal? Get in touch with us before you begin. A brief check beforehand can prevent a great deal of remedial work afterwards.

Would you like to buy terrazzo tiles or have an assessment of which products you need? Contact Tegel BV for personal advice or simply order samples online.

Tegel BV Website: www.tegelbv.com