Energy certification is mandatory for commercial and services buildings, public buildings, among others. The optimization of energy use in companies plays an important role in their competitiveness and an important environmental gain. Through energy certification, we characterize the installation and the main energy consuming equipment. We identify opportunities to reduce consumption, either by replacing equipment or by changing processes. Still.One is a Consulting company that dedicates its activity to areas such as Property Valuation, Property Valuation, Economic Valuation, Intangible Valuation, Equipment Valuation, Technical Expertise, Project and Construction Management, Construction Inspection, Management, Coordination and Safety in project and work. It was within the scope of these activities that Still.One requested the support of DELAB – JesusFerreira Consultores for the energy certification of a 5 000 m2 warehouse, located in Alfragide.