Bonding of TPU Tactile Paving – Adhesive Requirements and Common Mistakes

This instruction is part of the SOZI EOOD expert system for tactile paving and examines adhesive requirements for installing TPU tactile paving under real operating conditions.

Incorrect adhesive selection is one of the most common causes of detachment, raised edges and compromised tactile performance. In many cases, the issue lies not in the tactile paving itself, but in the use of an adhesive that is incompatible with the material and application conditions.

Why bonding is a critical element of the tactile system

TPU tactile paving elements are functional components for orientation and safety, designed to operate under constant pedestrian traffic. Unlike conventional floor finishes, they are often installed on existing hard substrates such as porcelain tiles, concrete or stone.

In such installations, the adhesive does not merely provide fixation. It becomes an active part of the system, required to absorb mechanical, dynamic and thermal loads without loss of adhesion.

Adhesive requirements for TPU tactile paving

When installing tactile paving made of TPU (thermoplastic polyurethane), the adhesive must provide both high bond strength and elasticity. Rigid adhesives or standard cement-based tile adhesives often generate stresses between the tactile element and the substrate, leading to long-term performance issues.

In practice, specialised polymer-based adhesives (polymer) are used. These cure through ambient moisture and create a strong, elastic and durable bond.

Comparison of adhesive types for TPU tactile paving

TPU tactile paving requires adhesives that combine strength with controlled elasticity. The table below compares specialised polymer adhesives with other commonly used bonding systems that are not designed for tactile paving applications.

Criterion	Specialised polymer adhesive ( polymer)	Cement-based tile adhesive (C1 / C2)	Universal construction adhesive / silicone
Chemical base	polymer	Cement-based	Various (acrylic, silicone, hybrid)
Compatibility with TPU	Yes – designed for elastic materials	No – rigid structure causes stress	Unpredictable, product-dependent
Elasticity	High (approx. 270%)	Low	Medium / variable
Adhesion to dense substrates	Very high, often without primer	Often insufficient without special preparation	Inconsistent under load
Resistance to dynamic loads	Yes – suitable for continuous pedestrian traffic	Limited	Often unsuitable for permanent loads
Indoor / outdoor use	Yes – suitable for INT and EXT	Class-dependent, often limited	Not always suitable for outdoor use
Temperature resistance	-40°C to +100°C (short-term up to +120°C)	Limited under freeze–thaw cycles	Composition-dependent
UV and ageing resistance	UV-resistant, weather-stable	Not UV-resistant	Possible degradation over time
Risk of raised edges	Minimal when correctly installed	High on dense substrates	Medium to high

Note: The data above illustrates general material behaviour. Actual performance depends on substrate condition, installation quality and compliance with technical instructions.

Typical bonding mistakes with TPU tactile paving

using cement-based tile adhesive
selecting adhesives with insufficient elasticity
poor substrate cleaning and preparation
uneven adhesive application
failure to respect curing and fixation times

Practical conclusions

Correct bonding of TPU tactile paving requires polymer-based adhesives compatible with both the material and the operating environment. Adhesive selection is a critical component of a reliable and safe tactile system, not a secondary decision.

Materials from the SOZI EOOD Expert System on Tactile Paving

The following publications are part of a unified expert system developed by SOZI EOOD for the proper planning, selection and application of tactile paving and tactile walking surface indicators, in accordance with accessibility requirements and applicable standards across Europe and the United Kingdom.