The most important factor for the protection of steel reinforcement in cementitious materials such as concrete is the alkalinity. As well as slowing down the penetration of atmospheric carbon dioxide, it delays to a certain extent the action of chloride ions. Both act at the molecular level in the form of discrete, individually mobile objects that can trigger steel corrosion. Therefore, maintenance materials designed to address these problems at the molecular level benefit from their own high pH value. To accomplish this an alkaline hydrogel based on diallyldimethylammonium hydroxide was developed which proved to be a multitool for modern building maintenance. The gel structure can be modified in order to tune macroscopic properties such as viscosity and stickiness relevant for applications. These are e. g. the restoration of the alkaline buffer of carbonated concrete, coupling material for the electrochemical chloride extraction, and crack injection, where the gel performs three functions simultaneously.