Construction industry is a human activities that most contributes to the world pollution. Recent studies conducted by the EU Commission in 2019 highlighted that buildings and construction materials are responsible for 39% of the global emissions of carbon dioxide and 50% of the raw materials extraction, as well as one-third of the world’s drinking water consumption. Analyzing the world of recycling mineral fibers, authors found that glass and basalt fibers from recycled waste, among other things, request less energy to obtain new filaments when compared to virgin fibers production. In this way, one can obtain a consistent reduction of energy consumption for building or retrofitting structures. In particular, authors explore in this study the benefits of using mineral fibers from recycled sources for strengthening brick masonry walls, carrying out diagonal compressive tests of one-head brick panels retrofiited with chopped fibers reinforced mortar. The aim of this study is twofold: understanding which type of chopped fibers is the most effective when dispersed in the mortar mix, i.e. basalt or glass fibers, and recognize the optimal location of the fiber reinforcement mortar with respect to the masonry panels. Under this perspective, three different set of panels are tested: (i) the reinforcing mortar is placed within the mortar joints of masonry panel; (ii) the reinforcing mortar is disposed as a double reinforcing layer on both the surfaces of the masonry panel, but the mortar joints are made out of plain mortar; (iii) the reinforcing mortar is placed both within the mortar joints of masonry bricks and as a double reinforcing layer on the surfaces of the masonry panel. Results are compared with reference panel made out of plain mortar and show that the most effective strengthening system is the one enriched by chopped basalt fibers. Generally, fiber reinforced mortar effectively strengthens both the loading and the post-peak capacity of the masonry panels, above all when used as coating layer on the external surfaces.