What is the primary use of soft solder in plumbing construction?

The primary use of soft solder in plumbing construction is for joining copper pipes and fittings. Soft solder is an alloy that typically contains tin and lead (or just tin in lead-free alternatives) and has a relatively low melting point, making it suitable for plumbing tasks.

When plumbing projects involve the installation or repair of copper piping, soft solder is applied to create a strong and watertight seal between the pipes and fittings. This process involves heating the joint area, allowing the melted solder to flow into the space between the metal surfaces, which then solidifies to form a reliable bond.

The selection of soft solder for this application is due to its effectiveness in providing a durable connection while successfully resisting corrosion that could stem from water flow. In contrast, other options, such as joining plastic pipes or connecting aluminum fixtures, utilize different methods, such as solvent welding or specialized adhesives, and thus are not suited for soft solder use.