Laying stone carpet – instructions & FAQ

A stone carpet is a seamless floor covering made of real natural stone grains (marble gravel) that are bound together into a solid surface with a binding agent. It is suitable for indoor and outdoor areas and is a modern alternative to tiles or other types of flooring.

Our complete stone carpet set for 2 m² is available starting at €129 – for the smallest set size, this corresponds to approximately €64.50/m² in material costs. For larger areas, the material price per square meter decreases.

The exact costs depend on the area, application, marble gravel color, and system structure. Any potentially required sealing is not included in the complete set and must be considered separately depending on the substrate and area of application.

A stone carpet is durable, easy to maintain, and seamless. It is suitable for both indoor and outdoor use and offers many design possibilities through various colors and natural stone granules.

Further advantages include a pleasant barefoot feel, a modern look, and versatile application options for terraces, balconies, stairs, and living spaces. When professionally installed, a stone carpet is also weather- and frost-resistant in outdoor areas.

The most important difference: a stone carpet is seamless. This creates a uniform, modern appearance without tile joints.

The textured surface can—depending on the grain size and surface finish—provide good slip resistance, especially in outdoor areas. Furthermore, a stone carpet can be laid directly onto firmly bonded, prepared tiles, so the old flooring does not need to be removed.

A stone carpet can be laid almost anywhere – both indoors and outdoors.

• Indoors: Living areas, hallways, kitchens, bathrooms, stairs, commercial spaces, and showrooms
• Outdoors: Terraces, balconies, loggias, garden paths, pool surrounds, and exterior stairs

A prerequisite is a clean, load-bearing, and level substrate such as concrete, screed, or firmly adhered tiles.

Yes, a stone carpet is very well suited for balconies, terraces, and other outdoor areas.

Prerequisites include a stable, clean, and professionally prepared substrate, suitable waterproofing beneath the stone carpet, and a slope of at least 2% so that water drains reliably and no standing water occurs.

Fittingly: our complete set for outdoor use and our products for balcony & terrace.

We offer three coordinated complete sets:

• Complete set for outdoor use – for patios, balconies, and other outdoor surfaces
• Complete set for indoor use
• Complete set for pool surrounds

All project solutions at a glance: Ready-made solutions for your DIY project

Our complete sets contain the coordinated amount of primer, quartz sand, binding agent, marble gravel, and smoothing agent.

A sealant is not included, as the required structure varies depending on the substrate and area of application.

Our consumption calculator automatically calculates this for our complete sets. Simply select the desired marble gravel color and enter the area in m² – the required quantities will be calculated immediately.

To the consumption calculator: Complete set for outdoor use, Complete set for indoor use or Complete set for pool surrounds.

For a layer thickness of approx. 8 mm, you will need about 12.5 kg of marble gravel and 1 liter of TECHPUR Stone Binder per m². A 25 kg bag of marble gravel is therefore sufficient for approx. 2 m².

For a greater layer thickness, consumption increases accordingly. Our complete set consumption calculator calculates the quantity automatically.

Bauchemie.at currently offers 14 marble gravel colors – even more shades are available as sample tiles. You can find all colors in our marble gravel colors category.

Tip: With our sample tiles (12.5 × 12.5 × 2 cm, marble gravel 2–4 mm, unsealed), you can check the color and texture at home in advance. Since this is a natural stone product, slight color variations between individual batches are possible.

The marble gravel for our stone carpet has a grain size of 2–4 mm.

With professional application and regular maintenance, a stone carpet is very durable and can be used for many years.

The key factors are surface preparation, the system used, the application, and the subsequent load. Outdoors, suitable waterproofing and sufficient slope are also important to prevent damage from moisture and frost.

Due to its textured surface, a stone carpet provides good conditions for a slip-resistant effect. The actual slip resistance depends on the grain size, the binder, any potential sealant, and the surface finish.

Choosing a suitable system is particularly important for terraces, balconies, and stairs. A specific slip resistance class can only be guaranteed if the respective system structure has undergone appropriate testing and classification.

Yes, a professionally installed stone carpet is frost- and weather-resistant.

A prerequisite is that water can drain away unimpeded: in outdoor areas, this requires a suitable waterproof membrane beneath the stone carpet and a slope of at least 2%.

Suitable surfaces include concrete, cement and anhydrite screeds, as well as firmly adhering tiles.

• Concrete, e.g., floor slab, screed, or concrete patio
• Cement screed or anhydrite screed
• Tiles

Each substrate must be prepared in advance by sanding or abrasive blasting to ensure optimal adhesion of the primer.

Yes, concrete is a very suitable substrate for stone carpets – provided it is load-bearing, sufficiently dry, and professionally prepared.

The substrate must be free of dust, oil, grease, loose particles, and other substances that could impair adhesion. We recommend mechanical preparation, e.g., through diamond grinding, followed by thorough vacuuming of the grinding dust. This is then followed by the primer.

Yes, a stone carpet can be laid over existing tiles, provided they are firmly bonded to the substrate and structurally sound.

Loose or damaged tiles must be removed or repaired beforehand. Then, thoroughly clean and mechanically prepare (sand) the surface so that the subsequent layers will adhere. This is followed by a suitable primer. For balconies, terraces, and other exposed areas, we additionally recommend a waterproofing layer beneath the stone carpet.

The substrate is mechanically sanded—ideally using a diamond cup wheel—or blasted, and then thoroughly vacuumed.

It must be firm, load-bearing, clean, dry, and free of loose particles, oil, and grease. Remove or repair loose or damaged tiles beforehand.

Yes. If the underfloor heating is located in the screed, the stone carpet can be laid over it quite normally.

The screed is prepared like any other substrate: sanded, vacuumed, and primed.

Yes, for outdoor areas: For balconies, terraces, and other surfaces exposed to the elements, we generally recommend waterproofing under the stone carpet. It protects the substrate from penetrating moisture and frost damage.

The waterproofing is applied after the primer and before the stone carpet. The exact system structure must always be tailored to the substrate and structural conditions.

Important: Waterproofing is not included in our complete stone carpet sets and can be ordered separately – see products for balcony & terrace.

The primer is applied and distributed evenly over the prepared surface using a paint roller.

If working without waterproofing, sprinkle the quartz sand directly into the fresh primer.

Quartz sand creates a non-slip surface and improves the adhesion of the stone carpet.

• Without waterproofing: Scatter quartz sand into the still-fresh primer.
• With waterproofing: Scatter quartz sand into the final, still-fresh layer of the waterproofing.

After it has dried completely, thoroughly vacuum up any excess, unbound quartz sand. The stone carpet can then be laid.

Edge profiles provide a clean, stable edge finish and prevent stones at the edge from breaking off.

They simplify installation by defining the layer height, protect heavily used edges on stairs or terraces, and create a clean transition to walls or other floor coverings. You can find matching profiles under Edge profiles.

Cut the profiles to size so that they are flush everywhere, then fasten them at specific points with PU adhesive.

The spot fastening allows for optimal drainage of the stone carpet downwards. Finally, level and remove any excess adhesive with a knife or a trowel.

You can lay a stone carpet in six steps: prepare the substrate, apply primer, seal for outdoor areas, mix marble gravel with binding agent, lay and smooth, and allow to cure. Our complete sets contain all the coordinated materials. A professionally prepared substrate, the correct system structure, and careful application are essential.

1. Prepare the substrate: The substrate must be firm, load-bearing, clean, dry, and free of loose particles. Depending on the substrate, sand it down and then vacuum thoroughly.
2. Apply primer: Apply the appropriate primer evenly. If no additional sealing is required, scatter the quartz sand directly into the fresh primer.
3. Create sealing for outdoor areas: For balconies, terraces, and other outdoor surfaces, sealing is required depending on the substrate. The quartz sand is then scattered into the final, fresh layer of the sealing – not into the primer. Outdoors, a sufficient slope is important.
4. Mix marble gravel and binding agent: Mix the marble gravel with the specified amount of binding agent until all stones are evenly coated. Since marble gravel is a natural product, we recommend mixing material from several bags to even out color differences.
5. Lay and smooth the stone carpet: Apply the mixture evenly to the required layer thickness, then compact and smooth it using a smoothing trowel. The smoothing agent prevents the mixture from sticking to the trowel.
6. Allow to dry and cure: Do not walk on the surface for about 24 hours; furniture can be placed after approx. 3 days, and the material is fully chemically cured after approx. 7 days. Do not cover the surface with tarpaulins or other air-impermeable coverings during the curing process.

Detailed step-by-step instructions (PDF):

• Stone carpet installation guide for outdoor areas
• Stone carpet installation guide for indoor areas
• Stone carpet installation guide for pool surrounds

Video guide: Easily install a stone carpet – step-by-step guide | Bauchemie.at (YouTube)

For our marble gravel with a grain size of 2–4 mm, we recommend a layer thickness of approx. 8–10 mm.

At approx. 8 mm, about 25 kg of marble gravel and 2 liters of TECHPUR Stone Binder are required for 2 m². A uniform layer thickness is important for a homogeneous surface and sufficient stability.

Mix the marble gravel with the binder to create a homogeneous mass (binder content approx. 8% of the stone weight) and apply it evenly with a trowel to the height of the edge trim (approx. 8–10 mm).

If vertical surfaces are also being covered, always work on these first – this way, no stone carpet mixture will fall onto horizontal surfaces that are already finished.

For vertical surfaces, mix the marble gravel with TECHPUR Stone Binder Vertical – typically about 2 liters of binder per 25 kg of marble gravel.

1. Prime the vertical surface with the binder first (approx. 300 g/m²).
2. Apply the stone carpet mixture evenly with a trowel and level it with the height of the edge profile – a maximum of 8 mm to ensure the material holds securely.

Yield: A 4-liter container of Stone Binder Vertical is sufficient for approx. 2 m² of vertical surface area.

Stone Binder Vertical is specially developed for vertical outdoor surfaces (walls, plinths, steps) and prevents the material from sagging.

Yes, installation on stairs is possible. For vertical surfaces (risers), the specially developed TECHPUR Stone Binder Vertical is required. For clean, protected stair edges, our edge profiles are suitable.

First, distribute the stone carpet evenly (approx. 10 mm), then compact it with the trowel using light pressure, and only then smooth it finally.

After compacting, clean the tool, spray it lightly with smoothing agent, and smooth the surface finally – this prevents the stone carpet from sticking to the trowel.

In short: Always use the solvent-free binder for indoor areas – both versions are possible for outdoor areas. Both TECHPUR Stone Binders are single-component, transparent, and fully aliphatic.

• solvent-based binder (outdoor): Contains volatile organic compounds (VOCs) that evaporate during curing. It has a stronger odor and is more harmful to health if ventilation is inadequate – therefore not suitable for indoor areas. Consumption: approx. 1 liter per m².
• solvent-free binder (indoor & outdoor): Solvent-free with 100% solids content, low odor, more environmentally friendly, and resistant to plasticizers from car tires. Consumption: approx. 1 liter per m².

After about 24 hours the stone carpet is walkable, after 3 days furniture can be placed on it, and after 7 days it is fully chemically cured and can withstand full loads.

Do not cover the surface with tarpaulins or other airtight materials during the curing process.

A stone carpet should be installed at a minimum temperature of 5–10 °C so that the binder can cure optimally.

At lower temperatures, the material cures more slowly and not optimally. Therefore, plan the installation for outdoor areas for a sufficiently warm day.

Thanks to its open pores, a stone carpet in outdoor areas can be easily rinsed off with clear water.

For a more thorough cleaning, spray the surface with TECHPUR Stone Carpet Cleaner, work it in with a brush, and then rinse thoroughly with water.

For standard indoor areas, TECHPUR Porenfüller AC is suitable, while for outdoor surfaces, pool surrounds, and permanently wet areas such as showers, use TECHPUR Porenfüller Innen & Außen – Dauernassbereich.

• TECHPUR Porenfüller AC – solvent-free and fully aliphatic, for indoor surfaces without constant moisture exposure (living spaces, hallways, offices, stairs).
• TECHPUR Porenfüller Innen & Außen – Dauernassbereich – weather and UV-resistant, for bathrooms, showers, balconies, terraces, and pool surrounds.

Both are applied to the fully cured, clean, and dry stone carpet and worked evenly into the pores. Approximate consumption: approx. 1.0–1.2 kg/m².

No, a sealant is not mandatory – however, it makes cleaning easier, and in areas constantly exposed to moisture, such as showers, it is necessary.

A pore filler closes the open pores so that dirt does not settle as easily. For outdoor use, the following applies: if the surface is sealed, water can no longer drain downward through the stone carpet. In that case, a professional, well-draining sub-base with a slope is particularly important, and standing water must be avoided at all costs.

Our TECHPUR Stone Binders are fully aliphatic – aliphatic binders are considered light-fast and, unlike aromatic binders, practically do not yellow under UV light.

This makes the stone carpet suitable for sunny terraces, balconies, and pool surrounds as well. The pore fillers are also aliphatic; the Indoor & Outdoor pore filler is additionally explicitly weather- and UV-resistant.

Yes – however, in the bathroom and in the shower, the stone carpet must be sealed with a pore filler suitable for permanently wet areas. The TECHPUR Pore Filler Interior & Exterior – Permanently Wet Areas is suitable for this purpose.

As with any flooring in showers, a professional waterproofing layer must also be present underneath. The AC pore filler for interior use is not suitable for permanently wet areas.