Plumbing means making holes for pipe to travel through a building, and often big holes, in awkward places, through framing you can barely reach. The best drill bits for plumbers combine holesaws for sized pipe openings with extra-length and auger bits that push through joists and studs in a single clean pass.
What to Look For
Two things drive your bit choice: the diameter of the pipe and the depth of material you must cross. Supply and drain lines need openings large enough to pass the pipe plus any insulation or room for expansion and movement, so hole size ranges widely from small copper runs to large drain stacks. Reach matters just as much. Drilling through a stack of joists or a deep stud bay demands a bit long enough to finish the hole without stopping to reposition, because a hole started from two sides rarely lines up. A durable edge that shrugs off the occasional nail or screw saves you a ruined bit mid-job.
The Best Type of Bit
Holesaws own the large-diameter openings, while wood auger and extra-length bits handle the long, straight bores that carry pipe through framing. Keep both formats on the truck so you are ready for either job the moment you open a wall.
- Holesaws: clean, sized holes for passing pipe through plates, blocking and subfloor.
- Extra-length bits: reach across multiple joists or deep cavities in one uninterrupted pass.
- Wood augers: a screw tip pulls the bit through thick framing with far less effort and push.
- Material: bi-metal and hardened edges survive the occasional hidden nail strike.
Protecting the Structure
Boring through joists and studs is governed by where and how large your holes can be, so plan runs that keep the framing sound and stay clear of edges and load paths. A sharp bit that cuts cleanly, rather than tearing and splintering, leaves stronger holes and a tidier job that will pass inspection. Centre your holes and keep them consistent so pipe runs stay straight, fully supported, and free of stress points that could work loose over time.
Drilling Deep and Straight
Long bits wander if you rush them, so start square to the surface, let the auger tip pull the bit in, and clear chips on long bores to keep the flutes from binding. For very deep runs, an extra-length bit finishes what a standard jobber bit cannot even reach, and a slow, steady speed keeps the hole true rather than letting the bit skate off line. A little wax or lubricant on the shank eases a long bit through dense old-growth framing and reduces the heat that dulls an edge. When a run has to cross an obstruction you cannot reach with a standard bit, an extra-length auger reaches where a jobber bit gives up. Our American-made bits are built to bore straight through framing job after job, which is exactly what a reliable, leak-free pipe run depends on.