Having a specialized company with a minimum of 5 years of experience and approval from a consultant for thermal and moisture insulation works is important because it ensures that the insulation works will be implemented by a company with the necessary expertise and experience to carry out the task effectively. 

This will help to ensure that the insulation system is installed correctly and to the required professionalism and effectiveness, which is crucial for the long-term performance and durability of the system. 

Additionally, having approval from a consultant will provide an extra layer of quality control and assurance that the insulation works meet the required standards and specifications.