For drilling studs and plates for supply pipe, the Bosch DSB5010 spade set covers the common 3/4 and 1-inch holes for 1/2 and 3/4-inch PEX or copper. For long runs of holes, an auger set like the Irwin Speedbor Max is easier, and the Klein 53722 extends a flex bit for drilling inside finished walls. Check your framing code before boring.
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This guide covers boring wood framing for water supply lines.
Bits for boring framing, compared
| Tool | Type | Choose it when |
|---|---|---|
| Bosch DSB5010 | 10 spade bits, 1/4 to 1-1/4 in. | Occasional holes through studs and plates for supply lines |
| Irwin Speedbor Max IWAX128PC | 8-piece auger bit set | Lots of holes in a run, where a cleaner, self-pulling bit saves effort |
| Klein 53722 | 54-inch flex bit extension | Drilling between walls or through several rafters with a flex bit |
Spade bits are cheap and fast for a few holes. Auger bits pull themselves through and clear chips better on long runs. For big holes for drains, plumbers usually step up to self-feed bits and a right-angle drill; our right-angle drill guide covers that setup.
What size hole for each pipe
Size the hole to the pipe’s outside diameter plus a little room. Half-inch PEX and copper have a 5/8-inch outside diameter, and 3/4-inch has a 7/8-inch outside diameter, so a 3/4-inch bit is a common choice for 1/2-inch lines and a 1-inch bit for 3/4-inch lines.
A little clearance lets PEX expand and contract without rubbing and makes pulling the pipe easier. Too big a hole wastes stud strength.
Framing codes limit how large a hole can be and how close to the edge it can sit, and those rules differ for studs, joists and engineered lumber. Check the framing code your area uses, or the lumber maker’s instructions for I-joists and LVL, before you drill. Where the pipe ends up close to the stud face, protect it with a nail plate; our nail plate guide explains where.
Bosch DSB5010: the everyday spade set
Choose the Bosch DSB5010 for a general spade bit set. Bosch lists the DSB5010 (maker page: www.boschtools.com/us/en/daredevil%C2%AE-spade-bit-sets-44100-ocs-ac/) with ten bits: 1/4, 3/8, 1/2, 9/16, 5/8, 3/4, 7/8, 1, 1-1/8 and 1-1/4 inch, which covers the common 3/4 and 1-inch holes for supply lines.
Bosch describes the Daredevil line with a full-thread tip that pulls the bit through 2×4s, a contoured paddle for chip removal and spur-and-reamer tips for cleaner holes, and claims up to 10 times faster drilling than conventional spade bits; that is the maker’s claim, not our test.
If you want more in-between sizes, Bosch’s same page lists the 12-piece DSB5012 with 11/16 and 13/16-inch bits added, and the 13-piece DSB5013P that runs up to 1-1/2 inch. For most supply-line work, the ten sizes in the DSB5010 are enough, and the 1-1/4-inch bit handles a 1-inch line.
On October 15, 2026, the standard new offer sold by Amazon.com showed stock with model DSB5010.
Check Bosch DSB5010 Daredevil spade bit set on Amazon →
Irwin Speedbor Max IWAX128PC: auger bits for long runs
Choose the Irwin Speedbor Max IWAX128PC when you are boring many holes in a row, like a PEX home run through a line of studs. The listing describes an 8-piece Speedbor Max drill bit set for wood. Irwin’s site was down for maintenance when we checked, so confirm the sizes in the set on the package.
On October 15, 2026, the standard new offer from a third-party seller showed limited stock with model and part IWAX128PC.
Check Irwin Speedbor Max IWAX128PC auger bit set on Amazon →
Klein 53722: flex bit extension for fishing walls
Choose the Klein 53722 when you are using a flex bit to drill down through a top plate or across several framing members you cannot reach. Klein says (kleintools.com) it connects to the end of a flex bit to extend its length, fits flex bits 3/4 inch and larger, has a 5/8-inch connection diameter, and suits drilling between walls or through several rafters. It is 54 inches long with a 1/4-inch shank.
A flex bit is a long, bendable bit for drilling through a top or bottom plate from inside a finished wall. Run it slowly, steer it with a bit holder or guide, and many flex bits let you hook a pull line on the tip so you can draw the line back through the hole as you withdraw.
On October 15, 2026, the standard new offer from a third-party seller showed stock with model and part 53722.
Check Klein 53722 54-inch flex bit extension on Amazon →
Spade, auger, self-feed or hole saw?
Each bit has a job. Spade bits are the cheapest way to make a few holes up to about 1-1/4 inch in studs. Auger bits have a screw tip and spiral flutes that pull the bit through and lift chips out, so they are steadier in deep holes and long runs.
Self-feed bits cut larger holes, such as those for 2-inch and bigger drains and vents, through plates and joists, and they need a strong drill, often a right-angle model. Hole saws cut clean holes in thin material such as subfloor or cabinet backs; our hole saw arbor guide covers the arbor side.
For a typical bathroom rough-in you may use all of them: a spade or auger bit for the supply lines, and a self-feed bit for the drain and vent.
Drill and bit care
Big spade and auger bits need torque more than speed. Run the drill at its low gear for bits over 3/4 inch, and keep a firm stance. Cordless drills with a side handle are common on the job.
A dull spade bit burns and wanders. You can touch up the cutting edges with a fine file, keeping the original angle; our file set guide covers files. Replace bits with bent spurs or a damaged tip rather than forcing them.
Watch for nails and screws in old framing. Hitting one ruins a spade edge instantly and can kick the drill.
Drilling safely and cleanly
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Check behind the surface first. A stud finder that shows wiring and pipes helps; our stud finder guide covers those. Shut off power to circuits in the wall if you are unsure.
Let the bit do the cutting with steady pressure. Spade and auger bits can bind and twist the drill when they break through; use the side handle and keep your wrists out of line with the drill.
Drill holes in a straight line, using a string or laser, so the pipe slides through without binding. Keep holes near the center of the stud where your code allows.
Frequently asked questions
What size spade bit for 1/2-inch PEX?
Half-inch PEX has a 5/8-inch outside diameter, so a 3/4-inch bit is a common choice. Check your framing code for hole limits.
What size hole for 3/4-inch PEX or copper?
Both have a 7/8-inch outside diameter, so plumbers often use a 1-inch bit.
Spade bit or auger bit for plumbing?
Spade bits are cheap and fine for a few holes. Auger bits clear chips better and are easier on long runs of holes.
What sizes are in the Bosch DSB5010?
Bosch lists 1/4, 3/8, 1/2, 9/16, 5/8, 3/4, 7/8, 1, 1-1/8 and 1-1/4 inch.
Can I bore any size hole in a stud?
No. Framing codes limit hole size and edge distance, and engineered lumber has its own maker rules. Check them before drilling.
How we chose
This document-based guide makes no hands-on testing claim. We read Bosch’s Daredevil spade bit set page and Klein’s 53722 page; Irwin’s site was down, so its set is described from the listing. On October 15, 2026, all three linked standard new offers showed stock. Read our selection method and about Plumbing Picks.
Primary sources
- Bosch Daredevil spade bit sets (maker page: www.boschtools.com/us/en/daredevil%C2%AE-spade-bit-sets-44100-ocs-ac/): DSB5010 sizes and features; speed claim is the maker’s.
- Klein Tools 53722 flex bit extension (kleintools.com): fits 3/4 in. and larger flex bits, 5/8 in. connection, 54 in., 1/4 in. shank.