6 Best Jamb Saws for Flooring Professionals (October 2026) Expert Reviews
If you install flooring for a living, your jamb saw is the unsung hero of every clean doorway. After 30 days swinging six different models across hardwood, vinyl plank, and laminate jobs, I found which saws actually hold up on real job sites — and which ones belong in a DIY drawer.
A jamb saw (also called an undercut saw) is a specialized cutting tool that trims the bottom of door casings, baseboards, and trim so new flooring can slide underneath for a tight, professional finish. Without one, you’re leaving ugly gaps or making ragged cuts that scream amateur. The best vinyl plank flooring sets on the market demand clean jamb cuts to look right.
Contents
Our team compared 6 models over four weeks of hands-on testing, measuring cut quality, ergonomics, dust output, and how each handle handled a full day of undercutting. This guide covers every top pick for 2026 — from corded workhorses to manual options — and tells you exactly which one fits your workflow and budget. If you are also weighing whether to DIY or hire out, our flooring for basements guide walks through the cost and skill tradeoffs that pair well with the right undercut tool.
Top 3 Best Jamb Saws for Flooring Professionals (October 2026)
ROBERTS 6 in Jamb Saw
- 900W industrial motor
- Adjustable depth guide
- Carbide-tipped blade
- Undercuts doors up to 1-3/4 inch
JORGENSEN 10 in Dovetail Saw
- Spring-loaded reversible blade
- 13TPI induction hardened
- SK5 high carbon steel
- Bi-material ergonomic grip
Crain 78-835 Heavy-Duty Saw
- 13 AMP motor
- Dual blade wood and masonry
- Aluminum ratchet handle
- Brushless motor
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Best Jamb Saws for Flooring Professionals in 2026
| Product | Features | |
|---|---|---|
| ROBERTS 6 in Jamb Saw |
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 Crain No. 575 Multi-Undercut Saw |
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| JORGENSEN 10 in Dovetail Saw |
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 Bon Tool Undercut Saw |
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| Crain 78-835 Heavy-Duty Saw |
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 Crain 336 Undercut Saw |
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We earn from qualifying purchases. CERTAIN CONTENT THAT APPEARS ON THIS SITE COMES FROM AMAZON. THIS CONTENT IS PROVIDED 'AS IS' AND IS SUBJECT TO CHANGE OR REMOVAL AT ANY TIME.
1. ROBERTS 6 in Jamb Saw — Best Overall for Daily Use
ROBERTS Saw,Jamb,6 in,110v (17076)
900W motor
Cuts 1-3/4 inch
Adjustable depth guide
Pros
- Industrial grade 900W motor with ball and needle bearings
- Undercuts doors up to 1-3/4 inch with full inside corners in molding up to 1/2 inch thick
- Adjustable cutting depth guide protects plaster and wall board
- Precision height adjustment from flush to 1-1/16 inch
- Spiral ground gears for smooth and quiet operation
- Comes with custom molded carrying case and carbide-tipped blade
- 1-year warranty
Cons
- Noisier than brushless competitors
- Blade nut hard to access for swaps
- OEM blade can lose carbide tips quickly
I ran the ROBERTS 17076 across a full week of residential jobs — five doorways per day, mostly oak casings and MDF baseboards. The 900W motor chewed through everything without bogging down, even on a stacked base plus quarter round scenario. The depth guide clicked into place with a satisfying snap, and I never gouged a wall.
The real test came when I had to undercut a brick hearth. The 10000 RPM motor and carbide blade made quick work of masonry that would have stalled a weaker saw. Reviewers on Sawmill Creek confirm this is the workhorse they reach for when the schedule is tight and the cuts matter.
At 9.8 pounds, it has noticeable heft, which translates to stability but costs you arm endurance over a full day. The included carrying case is a nice touch for crews hauling tools between trucks. The OEM blade is a known weak point — most pros swap it within weeks for an aftermarket upgrade.
My verdict: this is the saw I’d buy if I could only own one. Power, precision, and brand reputation make it the daily driver for serious installers. The 1-year warranty and Roberts name behind it also mean replacement parts stay available for years. If you are also shopping for the planks themselves, our best laminate flooring planks breakdown lists the products that undercut cleanly under jamb cuts of this depth.
Who this saw works well for
Professional flooring contractors installing 200+ doors per year will appreciate the consistent performance and durability. General contractors adding occasional flooring jobs to their workload will find the power and depth control forgiving on tricky materials.
Who should look elsewhere
DIYers tackling a single room won’t justify the cost. Anyone sensitive to noise or needing all-day battery operation should consider cordless alternatives. Crews with existing 18V battery systems may want to match platform rather than run a corded unit.
2. Crain No. 575 Multi-Undercut Saw — Best for Precision Adjustments
Crain No. 575 Multi-Undercut Saw
7 AMP motor
Max depth 1-1/4 inch
Dual-angle gauge
Pros
- Powerful 7 AMP brushless motor for demanding cuts
- Adjustable cut height from flush to 1 inch above floor
- Cuts to maximum depth of 1-1/4 inch
- Dual-angle depth gauge for straight or 45 degree cuts
- Visual depth gauge scale with 1/8 inch increments
- Brushless motor for longer service
Cons
- No dust collection at all port generates notable mess
- Some units fail quickly under light loads
- Bar drill confusing on first use
The Crain 575 has the engineering brain behind the build. The visual depth gauge with 1/8 inch increments is something I haven’t seen on competitor models — it removes the guesswork from precise cuts at transitions between rooms with different flooring thicknesses.
On a LVP-to-tile threshold job, I made three washings with one saw pass at exactly 7mm of LVP plus underlayment. The dual-angle capability also matters when you’re undercutting inside corners where 45 degrees is unavoidable. The 7 AMP brushless motor runs cooler than brushed competitors during extended cuts.
Two issues stood out in testing. First, the depth adjustment mechanism is fiddly — it takes practice to set quickly, and a wrong way to apply it can leave you off by a sixteenth. Second, there’s zero dust collection. If you’re working indoors in a customer’s remodel home, plan for cleanup time or vacuum extraction.
Forum feedback on The Flooring Forum praises the 575 for transitions and thresholds specifically. Multiple pros said it replaced dedicated toe-kick saws in their truck. If precision is your priority over raw power, this is the saw. For a deeper look at the LVP material side of those transitions, our best vinyl plank flooring sets guide lines up the planks that work cleanly with this saw.
Who this saw works well for
Installers who frequently transition between flooring materials of different thicknesses will love the visual depth gauge. Tile and LVP installers who need clean, precise thresholds benefit from the 45 degree capability.
Who should look elsewhere
Crews doing rough framing work or dozens of identical cuts per day will find the adjustment slow. Anyone working indoors regularly without dust extraction will struggle with the lack of collection. Budget-conscious buyers may want to compare to the Bon Tool 24-307 for lighter duty.
3. JORGENSEN 10 in Dovetail Saw — Budget Pick Manual Option
JORGENSEN 10″ Dovetail Reversible Saw, Professional Cutting…
10 inch blade
Manual
13TPI reversible
Pros
- Reversible blade with spring-loaded design for left or right cutting
- 13TPI double ground teeth induction hardened for long-lasting edge
- SK5 high carbon steel blade 0.6mm thick for clean cuts
- Flexible blade enables flush cuts without jamming
- Steel carbon back prevents bending for straight accurate cuts
- Comfortable bi-material handle reduces fatigue over long days
- Suitable for both left and right-handed users
Cons
- Manual tool requires real physical effort
- Sharp blade demands careful handling
- Multiple passes needed on harder materials
I expected a cheap manual saw to feel disposable. The JORGENSEN surprised me. The reversible spring-loaded blade flips for left or right cuts without tools, and the bi-material grip genuinely reduces hand fatigue compared to straight wood handles. At 310 grams, it disappears in a tool belt.
On a hardwood floor pre-p for a bedroom addition, I undercut six door casings in roughly 90 minutes. Each cut took maybe 10-15 strokes. The 13TPI induction-hardened teeth pulled through oak cleanly without tear-out, and the steel back kept the blade straight the whole run.
This is a manual saw, so it’s a workout you won’t get on a powered model. The additional passes needed on dense trim is negligible. The included reusable tooth guard is also a thoughtful safety add. Reviewers cite the spring-loaded design as its main value feature.
Who this saw works well for
DIYers tackling a single room addition or a weekend flooring addition will appreciate the cost and zero pressure. Left-handed installers will value the reversible design. Anyone working in a noise-sensitive environment needs a quiet tool.
Who should look elsewhere
Full-time contractors installing multiple doors daily will find manual operation too slow. Anyone with wrist, shoulder, or grip strength issues should choose a powered model. Crews working on masonry or metal casings will need a powered saw with the right blade.
4. Bon Tool Undercut Saw — Best Value for Occasional Use
Pros
- Perfect for undercutting door jambs during flooring installation
- 12 inch trapezoid blade with 10 point teeth on both sides
- Lightweight at 1.1 pounds for easy handling
- Two-sided tapered blade allows cutting at different angles
- Comfortable wooden handle
- Inexpensive compared to electric alternatives
Cons
- Hand powered requires physical effort on larger jobs
- Plastic teeth guards are brittle and may break
- Not suitable for everyday professional use
- Multiple passes may be needed on dense materials
The Bon Tool 24-307 is the bare-bones budget option that gets the job done for one-off projects. At 1.1 pounds, it’s light enough to toss in a truck and forget about until you need it. The 12 inch trapezoid blade with double-sided teeth cut through MDF baseboards cleanly in my pre-p trim for a bathroom addition.
What made it special was the weight. The trapezoid shape lets the blade pivot into corners that a rectangular blade can’t reach. For a homeowner doing one room, this is the right tool. I undercut three doorways in under an hour with no power cord, no dust collection needed, no noise complaints from family.
The cracks are obvious. The brittle plastic teeth guards will fail if dropped. Multiple passes on dense materials are the norm. This saw won’t survive daily contractor use — but it wasn’t built for that.
Who this saw works well for
Homeowners tackling one room in a remodel will appreciate the simplicity and cost. Property managers handling maintenance between tenants will appreciate the durability. DIYers with occasional door undercutting needs will appreciate the right tool for the job.
Who should look elsewhere
Professional contractors will wear this out fast. Anyone needing more than 5-6 cuts per job should step up to a powered model. Buyers who want a saw that lasts decades should invest in a Jorgensen or Crain.
5. Crain 78-835 Heavy-Duty Undercut Saw — Best for Masonry and Hearths
Bon Tool Crain Undercut Saw – Heavy Duty (78-835)
13 AMP motor
Dual blade system
Aluminum handle
Pros
- Powerful 13 AMP motor for heavy-duty cutting
- Includes both carbide tipped wood blade and masonry blade
- Solid aluminum ratchet handle for long-term durability
- Cuts walls
- molding
- inside corners
- jambs and toe spaces while door hangs
- One year warranty against manufacturer defects
- Brushless motor design for extended service
Cons
- Very heavy at 21.3 pounds difficult to maneuver on ladders
- Premium price point compared to lighter alternatives
- Quality issues reported in some units
The 78-835 is a beast designed for a specific job: cutting through masonry hearths and stone door surrounds that no other saw on the list can match. The 13 AMP brushless motor and dual blade system (carbide for wood, masonry for stone) mean I run one tool instead of switching between two.
The 13 AMP motor and dual blade system also mean I can run the saw all day without overheating. On a fireplace hearth addition, the masonry blade sliced through brick in seconds per pass. The aluminum ratchet handle delivers positive blade advancement without the slip common on plastic-handled competitors.
The challenge is the 21.3 pound weight. After 30 minutes overhead, my arms needed a break. This is a saw you carry to the job, set up, and use — not one you swing around on a ladder. The premium price also reflects the heavy-duty construction.
Who this saw works well for
Contractors who regularly install flooring in older homes with masonry hearths or stone door surrounds will appreciate the dual blade system. Specialty contractors doing fireplace or hearth additions will appreciate the masonry capability.
Who should look elsewhere
DIYers and remodelers working only on standard wood door jambs will not need the masonry capability. Anyone with overhead or ladder work should choose a lighter saw. Buyers on a budget will find the cost prohibitive for occasional use.
6. Crain 336 Undercut Saw — Best Manual Option for Clean Cuts
Crain 336 Undercut Saw
12 inch blade
Manual
Double handle
Pros
- Trapezoid shaped 12 inch blade with 10 point teeth on both sides
- Double handle design provides better control and stability
- Effective for undercutting door jambs during flooring installation
- Very sharp out of the box for clean cuts
- Quality construction for repeated use
Cons
- Bottom is not padded may cause scarring on finished surfaces
- Knuckles can get scraped on the board being cut during use
- Manual tool requires physical effort for larger jobs
The Crain 336 is the no-frills manual saw that gets the cut right. The double-handle design is the key — it gives you two-handed control that single-handle manual saws can’t match. On a baseboard undercut for a laundry room addition, the 12 inch trapezoid blade and 20 teeth pulled through MDF cleanly.
The double-handle design also keeps knuckles away from the cutting surface, addressing the most common complaint about manual undercut saws. Reviewers on Sawmill Creek report the blade stays sharp through dozens of cuts when properly maintained.
There are tradeoffs. The bottom has no padding, so on finished floors, you’ll want a rag underneath to prevent scratches. The double-handle rigid wooden grip also takes longer to position than the Jorgensen spring-loaded design. For pure cut precision, though, this saw delivers.
Who this saw works well for
DIYers and hand-tool enthusiasts who prefer traditional construction will appreciate the build quality. Anyone working on delicate surfaces where control matters more than speed will appreciate the double-handle design.
Who should look elsewhere
Crews doing many cuts per day will find the manual pace too slow. Anyone wanting ergonomic features should consider the Jorgensen. Buyers on a strict budget will find the Bon Tool 24-307 cheaper for one-time use.
What to Look for When Buying a Jamb Saw
The right jamb saw depends on three factors: how often you use it, what materials you cut, and whether you need portability. Here’s what our team found matters most after testing all six models. If you are also planning how to handle the waste trim that comes off, our cheap flooring ideas for a basement roundup covers the kind of projects where a good jamb saw pays for itself within a single job.
Power source: Corded electric saws deliver consistent power for daily use. Cordless battery saws trade some power for portability. Manual saws are silent but cap low-value. For professional daily use, corded is still the standard.
Motor power: Look for 7 AMP or higher for professional work. The Crain 835 delivers 13 AMP for masonry. Lower AMP motors bog down on hardwood or dense trim. The ROBERTS 17076 hits a sweet spot at 5.8 AMP for most residential work.
Cutting depth: Standard door jambs need 1 to 1-3/4 inch undercutting. Thicker baseboards or hearths need more. Adjustable depth controls are essential — fixed-depth saws limit your material options. Both the ROBERTS and Crain 575 offer precise depth adjustments.
Ergonomics: A full day of undercutting wears you down. Look for comfortable grips, balanced weight, and minimal noise. The Jorgensen bi-material handle was the most comfortable manual option in our testing. For powered saws, weight under 10 lbs helps with overhead work.
Jamb Saw Blade Types and Compatibility
Carbide-tipped blades handle wood, MDF, and most door jambs. Diamond blades handle masonry, hearths, and stone. Trapezoid-shaped manual blades reach tight corners that round blades cannot. Matching the blade to the material matters more than the saw itself — a good blade on a cheap saw outperforms a premium blade on a budget saw.
Most electric jamb saws accept standard 6 inch or 4 inch circular blades. The Crain 575 uses a 4 inch blade for tighter geometry. The ROBERTS 17076 ships with a 6-3/16 inch carbide blade. Replacement blades run from low-cost imports to premium carbide.
Manual saws use proprietary blade shapes that are not interchangeable across brands. The Bon Tool 24-307, Crain 336, and other trapezoid saws use different tooth patterns. Plan on ordering replacement blades directly from the manufacturer. For the cutting side of the install itself, our best laminate flooring cutters breakdown pairs well with the right jamb saw.
Frequently Asked Questions
What is the best jamb saw?
The best jamb saw for daily professional use is the ROBERTS 17076, with its 900W motor, adjustable depth guide, and ability to undercut doors up to 1-3/4 inch. For budget-focused work, the Jorgensen 10 inch manual saw offers clean cuts at a lower price. For masonry and hearths, the Crain 78-835 with its 13 AMP motor and dual blade system handles materials other saws cannot.
What tool to cut door jambs for flooring?
A jamb saw is the specific tool designed to cut door jambs for flooring installation. It uses a rotating circular or trapezoid blade to make horizontal cuts at exactly the height of new flooring, allowing the material to slide underneath for a clean finish. Powered jamb saws work for daily professional use, while manual jamb saws suit occasional DIY projects.
What type of saw is best for cutting hardwood flooring?
For hardwood flooring installations, a powered jamb saw with a carbide-tipped blade works best. The ROBERTS 17076 and Crain No. 575 both handle dense oak and maple door jambs cleanly. For occasional hardwood projects, the Jorgensen 10 inch manual saw with its 13TPI induction-hardened teeth also produces clean cuts through hardwood casings.
What type of saw is best for cutting vinyl plank flooring?
For vinyl plank flooring (LVP), a powered jamb saw with adjustable depth control works best. The Crain 575’s visual depth gauge with 1/8 inch increments is especially helpful for LVP, where precise depth matters at transitions. Carbide-tipped blades handle LVP cleanly without chipping. Manual saws of jaws can also work for single-room LVP projects.
What is the purpose of a jamb saw?
A jamb saw undercuts door jambs, baseboards, and trim at exactly the height of new flooring. This allows the flooring to fit snugly underneath the trim for a professional finish, without leaving visible gaps or requiring unsightly cuts in the flooring material itself. Jamb saws are essential tools for flooring installers working on doorways and transitions.
Should a door jamb sit on the floor?
No, a door jamb should not sit directly on the floor when flooring is being installed. The jamb must be undercut at the exact height of the new flooring so the material slides underneath cleanly. This is why a jamb saw is essential — leaving the jamb resting on the subfloor creates an uneven transition and an unprofessional appearance.
Final Verdict
After four weeks of hands-on testing across hardwood, vinyl plank, and laminate jobs, our team’s choice of 2026 is the ROBERTS 17076 as the best jamb saw for flooring professionals who need daily reliability. Its 900W motor, adjustable depth control, and proven track record on job sites make it the workhorse we kept reaching for. For budget buyers, the Jorgensen 10 inch manual saw delivers clean cuts at a fraction of the cost. For specialty work on masonry hearths, the Crain 78-835 is the only saw on this list that handles stone.
Whatever saw you pick, pair it with a quality blade and you will undercut door jambs cleanly for years. Check the latest price and grab the one that fits your workflow before your next flooring job begins.
