The aim of this study was to develop a sustainable electromagnetic prototype to detect the interior deterioration of walls in buildings in order to mitigate uncertainty as it is a challenge to observe the interior state of walls without utilising destructive procedures. The method used was experimental, developmental and quantitative in its approach. The inductance, electric current, modulated frequency and power of the electromagnetic field were used to penetrate the constructed specimens, which were built of materials such as concrete, brick, adobe, plaster and fine sand and had walls with a thickness of less than 300 millimetres. The results show that the optimum value of the magnetic field was 0.18 µT, which was sufficient to penetrate 150 mm with densities between 1.0 and 2.4 g/cm3 and porosities between 11 and 60%. The current and wave each had a coefficient of determination R2 = 0.8914, and the average inductance value was 184 µH, which was established with an air core of radius 9.75 cm and with 19 turns with AWG-25 wire. The frequency-modulated signal ranged in the audible zone between 10 and 22 kHz. The presented prototype detects the interior deterioration of the walls of the building, and the signal is reflected on a metallic guide on the opposite side of the wall with a reading error of 5%. The use of this prototype does not represent a risk to the operator or the environment.