Projects / 8/26/2024

Waterproofing for the spa and thermal baths in the Grande Hotel Thermas

Complete systems supplied for installing ceramic and mosaic tiles along the wellbeing itinerary of a luxurious Portoguese hotel

Mapei provided complete systems for waterproofing substrates and installing ceramic tiles in several areas of the Grande Hotel Thermas in São Pedro do Sul, Portugal. This project enhanced the hotel's spa and thermal baths, ensuring durable and aesthetically pleasing surfaces.

The town of São Pedro do Sul is located in the central part of Portugal in the Montanhas Mágicas territory, an area much loved by the Portuguese and tourists alike for its natural landscapes, cultural heritage and, above all, its thermal water. This water, highly appreciated and used back in ancient Roman times because of its curative properties, flows naturally to the surface at a temperature of 68°C and is available for tourists and local residents at several establishments.

One of these is the Grande Hotel Thermas which, since 1919, offers its guests comfortable, elegant and relaxing surroundings, along with splendid views of the surrounding countryside.

In 2020 the hotel decided to extend its thermal baths services by creating a structure next to the existing one featuring a system of interconnecting caves, baths and indoor and outdoor swimming pools to create a wellbeing itinerary that also encompasses a spa area.

Mapei Portugal, the Portuguese subsidiary of the Group, also took part in the works by supplying complete systems to treat and waterproof substrates and to install ceramic and mosaic tiles in the swimming pools and on the floors and walls of the wellness and spa areas.

The substrates of the spas and swimming pools were waterproofed with MAPELASTIC SMART, before installing ceramic tiles or mosaic with KERAFLEX EXTRA S1. KERAPOXY DESIGN grout was chosen due to its aesthetic effect in many of the spa surfaces.

Safe installation for durable floor and wall coverings

In many of the swimming pools and in the baths and caves, the surfaces were waterproofed with a system that included MAPELASTIC SMART two-component cementitious mortar, which ensures a high level of flexibility and is particularly suitable for waterproofing hydraulic structures such as channels, swimming pools, baths and storage tanks.

In the case of the Grande Hotel Thermas, the first layer of mortar was reinforced with MAPENET P fibre glass mesh. The corners between adjacent walls and between walls and floors were waterproofed with MAPEBAND EASY rubber tape. Both MAPENET P and MAPEBAND EASY are manufactured and distributed on the Portuguese market by Mapei Portugal.

Ceramic and mosaic tiles were installed in the swimming pools and baths using KERAFLEX EXTRA S1 (now available as KERAFLEX EXTRA S1 ZERO*), a deformable cementitious adhesive with high wetting capacity, no vertical slip and extended open time.

The joints were grouted with ULTRACOLOR PLUS* cementitious mortar with fully offset residual CO₂ emissions or, where a more attractive aesthetic effect was required, with KERAPOXY EASY DESIGN acid-resistant, decorative epoxy mortar (available on the Portuguese market as KERAPOXY DESIGN). Thanks to innovative BioBlock technology, both types of grouts prevent the proliferation of bacteria and the formation of mould on the surface of joints, helping to keep surfaces more hygienic.

The adhesive used to install ceramic tiles on many of the walls of the wellbeing itinerary, on the other hand, was KERAFLEX, a cementitious adhesive with extended open time, which was chosen to install the wall tiles because of its high thixotropy.

The ceramic floors, on the other hand, were installed with KERABOND PLUS cementitious adhesive with extended open time, which was chosen for its good workability and because it adheres perfectly to all types of materials normally used in building work.

The expansion joints in all the ceramic and mosaic surfaces were sealed with MAPESIL AC pure acetic sealant characterised by high elasticity, durability and resistance to mould.

MAPETHERM SYSTEM was applied onto some of the façades of the news buildings, to ensure proper thermal insulation.

Ceramic and mosaic tiles were installed on many of the walls of the wellbeing itinerary, with KERAFLEX, a cementitious adhesive with extended open time, which was chosen due to its high thixotropy.

Project information

Grande Hotel Thermas, São Pedro do Sul (Portugal)

Owner: Geopor Lda

Period of construction: 2020 –2023

Period of Mapei intervention: 2020 – 2023

Design: Nuno Capela

Main contractor: JJ Construções, LDA

Installation company: JJ Construções, LDA

Intervention by Mapei: providing solutions for waterproofing substrates, installing ceramic and mosaic tiles on pools, floors and walls and installing a thermal insulation system

Mapei distributor: Revilaf 2

Mapei coordinator: Nuno Gomes, Mapei Portugal

Photos: Grande Hotel Thermas

*The products belonging to the ZERO line have their CO₂ emissions measured throughout their lie cycle in 2024 using Life Cycle Assessment (LCA) methodology, verified, certified with EPDs, and offset through the acquisition of certified carbon credits in support of forestry protection projects.