Execution of all work and provision of all services, including consulting, troubleshooting, descaling and maintenance, in the fields of sanitary installations, water networks, heating and sheet metal work, as well as the execution of all renovation and construction work; import, export and trade of all products related to the aforementioned activities; all real estate transactions in Switzerland and all participations in real estate companies in Switzerland are excluded, except for operations and participations related to buildings with exclusively commercial use.