Kathleno Siding Installation Tools, Siding Mounting Kit for Use with 5/16-Inch Fiber Cement Sidings, Lap Tools Gauge with Adjustable Reveals, Polycarbonate Body, 2 Pack

Overview

I tried the Kathleno siding gauges on a recent Hardie plank job to see if a budget-friendly set of clamps could really turn a one-person siding day into a realistic, repeatable workflow. In short: they can. These are simple, polycarbonate lap-siding gauges designed for 5/16-inch fiber cement, sold as a pair, with adjustable reveals from 4 to 8 inches in 1/4-inch steps. They function as a second set of hands—supporting the next course, keeping reveals consistent, and freeing you to nail without juggling a level, tape, and helper.

They’re not flawless, and they won’t solve every layout challenge around windows, corners, or eaves. But for long, straight runs, they substantially reduce setup time and fatigue while improving uniformity.

Setup and Adjustability

Adjustment is tool-free and straightforward. A simple stepped mechanism lets you dial in reveals between 4 and 8 inches in 1/4-inch increments. The detents are positive enough that I never worried about bumping the setting by accident, yet quick enough to change when I needed to drop or raise a course for tricky transitions.

A small note on the hardware: the reveal adjustment fastener is serviceable, but I found it can back off if you handle the gauges roughly or toss them in a bucket with other tools. Treat it like a precision jig, not a demo bar. If you want to bulletproof it, consider swapping to a nyloc nut of the same thread or keep a spare in your pouch.

On-the-Wall Performance

With the reveal set, you clamp each gauge onto the previously installed course, then rest the next board on the supports. The grips have rubber pads that protect prefinished siding, and the clamping force is ample for typical 12-foot fiber cement boards, provided you place the panel with some care.

A few observations from use:

• Clamping force: You don’t need to crank these down. Moderate pressure holds securely without marring. Over-clamping can bruise the finish or compress grit into the paint.
• Board placement: With a straight board, you can lift a full 12-footer into place, seat it into the gauges, and it stays put while you nail off. On mildly crowned or twisted boards, I still got good results, but I had to hand-register the middle or tack one nail quickly to keep the panel from walking.
• Hands-free nailing: Once the board is seated, you can shoot or hand-nail comfortably along the studs. The gauges don’t block the nailing zone, and they’re quick to pop free and move.
• Edge conditions: Around windows, doors, and corners, these are a partial solution at best. You still need layout marks, a short offcut as a temporary spacer, or separate shims. The gauges shine on open, uninterrupted runs.

The bottom line: for standard courses, the workflow becomes repeatable and calm. I ran consistent reveals without reaching for the tape every board, and that speeds you up more than you’d think.

Build Quality and Durability

The body is polycarbonate, not aluminum. That has pros and cons:

• Pros: lightweight, gentle on finished surfaces, won’t dent easily, and comfortable to carry all day.
• Cons: less rigid than metal if dropped, and more susceptible to UV aging if left in the sun for months.

The rubber pad on the grip is well-chosen; it’s grippy enough to hold position but soft enough that it didn’t scratch my prepainted boards. Do keep the pads clean: cement dust builds up quickly and turns any rubber into sandpaper. A quick brush or wipe every few boards keeps your finish safe.

I wouldn’t store these long-term on a sunny shelf. Polycarbonate can haze or embrittle after prolonged UV exposure. Hang them inside the trailer or in a toolbox and they should hold up fine for homeowner projects and occasional pro use.

Ergonomics

Ergonomically, they’re straightforward. The grip levers are easy to operate even with gloves, and they don’t pinch fingers. The units are light and easy to set one-handed while supporting a board with the other. Because they’re not heavy, you’re less likely to fumble them when moving up the wall. After a day’s work, I appreciated not having another pair of heavy clamps tugging at my belt.

Accuracy and Repeatability

The value proposition here is consistent reveals. The stepped adjustment locks repeatably, and because you’re indexing each course from the one below, the entire elevation stays uniform—assuming your first course is true and your starter strip is set correctly. I checked progress with a laser and level periodically, and the courses stayed steady.

One technique note: always register the new board firmly against the sheathing or furring before you shoot. If you clamp in a way that pushes the previous course outward, you can introduce a slight gap that telegraphs up the wall. The fix is simple—seat the panel and check flush before nailing.

Where It Falls Short

• Warped or crowned boards: The gauges don’t overcome board defects. For stubborn stock, plan on a tack nail at center or a helper hand to hold true while you fasten.
• Trim transitions: Around openings and near corners, you’ll still rely on layout marks, spacers, or a different jig. The gauges reduce, but don’t eliminate, measuring.
• Over-clamping risk: Squeeze too hard or leave them clamped too long and you can imprint the finish. Light pressure works best, and don’t leave them hanging on a board during a lunch break.
• Hardware retention: The adjustment hardware can loosen if you knock them around. A periodic check or a nyloc swap helps.
• Material choice: Polycarbonate is tough, but not as rigid as pro-grade aluminum. If you’re a full-time installer, you may want more robust gauges for daily abuse.

Who They’re For

• Solo installers and DIYers tackling fiber cement lap siding who want consistent reveals and a calmer workflow on straight runs.
• Small crews that want to free a helper from holding duties and keep hands on layout, cutting, or trim while one person nails courses.

They’re purpose-built for 5/16-inch fiber cement. If you’re working with other thicknesses or materials, look elsewhere.

Tips for Best Results

• Set your first course perfectly level. Everything keys off it.
• Use light to moderate clamp pressure. Let the rubber pad grip; don’t crush the finish.
• Keep the pads clean. Dust is abrasive.
• Don’t leave the gauges clamped when not actively nailing.
• Confirm your studs and nail pattern ahead of time; this keeps the nailing cadence smooth while the board is supported.
• For wonky boards, seat the middle first, pop a tack nail at a stud, then work outward.
• Store the gauges out of direct sun when the job’s done.

Value

These gauges hit a useful middle ground: priced for homeowners, capable enough for serious weekend projects, and fast to set up. There are heavier-duty aluminum options on the market that feel more “pro,” but they cost more. For occasional fiber cement installs or a one-house project, these deliver most of the productivity benefits at a friendlier price.

Final Recommendation

I recommend the Kathleno siding gauges for anyone installing 5/16-inch fiber cement lap siding, especially if you’re working solo. They make straight-run courses faster, safer, and more uniform, and they reduce the juggling act that usually comes with reveal management. Treat them as precision helpers—apply light clamping pressure, keep the pads clean, and stow them out of the sun—and they’ll turn a big siding day into something much more manageable. If you’re a full-time installer or routinely work in complex trim conditions, you may eventually want a more robust set or supplement these with additional layout jigs, but for most users and most runs, these are a smart, time-saving addition to the kit.