What is the impact of using a plumb-bob in a building project?

Using a plumb-bob in a building project plays a crucial role in ensuring straight and vertical walls. It consists of a weight suspended from a string, which indicates the direction of true vertical. By using a plumb-bob, construction workers can ascertain that their vertical lines are perfectly aligned, which is essential during the framing phase of construction. This alignment helps in maintaining structural integrity and prevents future issues such as leaning walls or misaligned frames, which could compromise the entire building's stability.

While the other options might relate to construction in different ways, they do not correctly reflect the primary function of a plumb-bob. For instance, insulation pertains to thermal properties, reducing construction time involves planning and efficiency beyond just tool usage, and leveling floors is addressed through different methods like levels or laser tools. Thus, the use of a plumb-bob specifically and effectively ensures that walls remain straight and vertical throughout the building process.