Short definition
A jackhammer is a heavy demolition tool that breaks concrete with a chisel- or point-tipped striker driven by an electric motor or compressed air. In plumbing, it breaks out a slab section to access underground drain lines for repair, replacement, or new branches — a basement bathroom add, an under-slab leak, a side-sewer access dig.
What it is
Electric residential-class jackhammers deliver 35 to 65 joules of impact — an order of magnitude more than a rotary hammer. Pneumatic versions (60+ CFM compressor, pro-only) push more. Bits are spade (general break-out), point or moil (concentrated breaking), and wide chisel (cutting trenches). Same SDS-Max or 1-inch hex shank as larger rotary hammers.
Rental rates run $60–$120/day for a 35-pound electric jackhammer (Home Depot, United Rentals). Pneumatic with compressor runs $150–$300/day combined. Buy is $400–$1,500 — only worth it for repeat work.
Why it matters to a homeowner
Slab work is common on basement-bathroom adds, under-slab drain repairs, and side-sewer access digs. Three rules are non-negotiable, and they apply to homeowner DIY just as much as to contractors:
- Silica dust. Concrete generates substantial respirable crystalline silica. OSHA’s PEL is 50 µg/m³ as an 8-hour TWA (29 CFR 1910.1053). Wet methods (water suppression) plus N95 minimum (P100 preferred) plus eye protection are the floor.
- Noise. Jackhammers run 100–115 dB. NIOSH’s REL is 85 dB TWA. Earmuffs (NRR 25+) plus foam plugs for full-shift work.
- Hand-arm vibration. Prolonged use causes nerve damage in fingers and hands. Anti-vibration gloves help; rotate operators on long jobs.
When a contractor says “we’ll need to jackhammer the slab,” that’s a normal step — ask for an estimate of how many square feet are coming out and how the slab will be patched.
Washington note
When slab work transitions to trench work below the slab, WA L&I trench safety rules (WAC 296-155 Part N) apply. Anything deeper than 4 feet (1.2 m) requires a competent person on site and a protective system per WAC 296-155-655. A homeowner DIY job that goes deeper triggers professional requirements — that’s the threshold where you stop and hire a contractor with the right registration and the right equipment.
Common variants and not the same as
- Jackhammer vs. rotary hammer. Jackhammer is for breaking out; rotary hammer is for drilling through. Different bits, different scales.
- Jackhammer vs. sledgehammer. Sledge is manual. For a small slab patch, sledge plus a cold chisel works at one-tenth the cost.
Common failure modes
- Hitting an unmarked pipe, cable, or rebar. Slab-locator inspection before breaking. WA’s call-before-you-dig (811) covers outdoor work; indoor slab work is on the homeowner.
- Skipping silica protection. No immediate symptoms; long-term lung disease.
- Vibration injury on long jobs. Rotate operators; use anti-vibration gloves.