Abstract : The optimization of the use of materials and energy, as well as the search for comfort and quality of life, are indispensable characteristics in the design of new projects. In this view, geopolymeric cements are an important alternative to high performance cement, which are produced from low cost raw materials, including agricultural and industrial waste. Among these materials are the geopolymers, which when reacted with an alkaline solution, react and harden due to their geopolymerization. The raw material (precursor material) for the production of geopolymers is silica and alumina rich materials, where the activation efficiency depends on the chemical and mineralogical composition of the raw material, as well as the proportion of the molar ratios of the components and the curing conditions. The most commonly used raw materials for this purpose are natural pozzolana and industrial waste. In this context, this dissertation approaches the development of a geopolymer mortar by means of the activation of metacaulim as the main source of aluminosilicate, sodium hydroxide as alkaline activating solution, sodium silicate as an inhibitor of efflorescence and aluminum powder of different sizes acting as a pore-generating agent. The results showed that the addition of aluminum powder as a pore generating agent has a direct influence on the porosity, density, consistency, mechanical strength and thermal conductivity of the obtained mortar. The use of the aluminum powder resulted in an apparent density reduction of 34%. The results of the mechanical properties tests indicate a resistance result of 88% on average in the first 24 hours, compared to the results of the tests obtained after 28 days of cure. And the results of thermal conductivity show significant gains with a variation of approximately 42% between the highest value and the lowest value found among the different formulations studied. Therefore, the use of aluminum powder to act as a pore-generating agent can be used in applications that require lighter materials and environments that require different values of thermal conductivity.