Largo Siding Two Fiber Cement Products, One Big Difference in the Details
If you've been researching siding for a home in Largo, you've probably noticed that "fiber cement" isn't a single product — it's a category. Cemplank and James Hardie both make fiber cement lap siding, panels, and trim, and at a glance in a showroom or on a spec sheet, they can look similar. Both are cement-based composite products designed to outperform wood and vinyl. But once you get past the surface, there are real differences in how these two companies engineer, finish, and warranty their products — differences that matter a lot on the Pinellas County coast, where hurricane-force winds, intense year-round UV, wind-driven rain, and salt air all take their toll on a home's exterior every single year.
We install exclusively James Hardie siding on the homes we work on, and we get asked "why not Cemplank?" often enough that it's worth laying out honestly. This isn't about telling you Cemplank is a bad product — it's a legitimate fiber cement siding made by a legitimate manufacturer (owned by Boral, now part of the Westlake building products group). But there are specific, practical reasons we've standardized on Hardie for homes in this climate, and you deserve to understand them before you sign a contract with any contractor, us included.
What Cemplank Gets Right
Give credit where it's due. Cemplank is genuine fiber cement — a mix of Portland cement, sand, and cellulose fiber, autoclave-cured for stability. That puts it in the same fundamental category as Hardie, and worlds ahead of vinyl or untreated wood siding in terms of durability basics:
- It's non-combustible, which matters for insurance considerations and fire safety alike.
- It resists rot, termites, and woodpeckers in a way that wood-based products can't.
- It holds paint and factory finishes better than wood siding over the long run.
- It's priced competitively, often coming in a bit below Hardie on material cost.
For a homeowner on a tight budget who wants to move up from vinyl or aging wood siding, Cemplank isn't a reckless choice on paper. The issue for us isn't the base material — it's what happens after that material leaves the factory and goes on a house that has to survive a Gulf Coast summer.
Where the Real Differences Show Up
Regional Engineering
James Hardie manufactures different formulations of its siding for different climate zones — its HZ5 product line, for example, is engineered specifically for hot, humid, storm-prone regions like the Gulf Coast and includes moisture-management features baked into the product itself. Hardie has invested heavily in publishing region-specific installation guidance and building code documentation, including ASTM and Miami-Dade/Florida Product Approval listings that installers and inspectors in Pinellas County rely on directly. Cemplank sells a general fiber cement product line without that same depth of climate-specific engineering and regional code documentation, which puts more of the burden on generic installation practice to make up the difference in a hurricane-prone market.
Factory Finish
This is the biggest practical difference for most homeowners. Hardie's ColorPlus Technology is a factory-applied, baked-on finish system with a documented multi-coat process and a specific finish warranty backing it. Cemplank siding is typically sold primed, meaning the final paint job depends on your contractor's crew and the paint product they choose — not a factory-controlled process. In a climate with year-round UV exposure and salt-laden air rolling in off Tampa Bay and the Gulf, the quality and consistency of that finish is what determines whether your siding still looks sharp in year eight or is already chalking, fading unevenly, and needing a repaint.
Warranty Structure
Hardie backs its siding with a non-prorated limited warranty (typically 30 years on siding products) that is transferable to a subsequent homeowner if you sell — a detail that matters for resale value. ColorPlus finishes carry their own separate finish warranty. Cemplank's warranty coverage exists but is generally less robust in both duration and structure, and the company's market presence and long-term support infrastructure are smaller than Hardie's, which is a real consideration if you ever need to file a claim ten or fifteen years down the road.
Installer Network and Availability
Hardie has built a large certified-contractor network (Hardie Preferred/Elite Preferred programs) with training standards, which makes it easier to find installers who genuinely know the product's fastening, clearance, and caulking requirements. Cemplank has a smaller footprint in Florida, which in practice means fewer local crews with deep, repeated experience installing it correctly under Florida's building code and wind-load requirements.
Side-by-Side: Cemplank vs. James Hardie HZ5
| Factor | Cemplank | James Hardie HZ5 |
|---|---|---|
| Base material | Fiber cement | Fiber cement |
| Climate-specific formulation | General product line | Engineered for hot/humid/high-wind regions |
| Factory finish option | Typically shipped primed | ColorPlus factory-baked finish available |
| Finish warranty | Limited, product-dependent | Separate finish warranty on ColorPlus |
| Siding warranty | Limited, shorter/prorated in some cases | 30-year non-prorated, transferable |
| Florida wind/impact documentation | Less extensive | Extensive FL Product Approval and code data |
| Local certified installer network | Smaller in this market | Larger, with formal training programs |
Why Installation Quality Matters as Much as the Product
Fiber cement siding, whether it's Cemplank or Hardie, is only as good as the installation. Both products need proper clearance from grade and roofing, correctly sealed joints, the right fastener pattern for Pinellas County's wind-load requirements, and careful attention to the areas most exposed to wind-driven rain — around windows, doors, and roof-to-wall transitions. A poor installation of top-tier Hardie siding will fail faster than a good installation of a lesser-known product. That said, when a manufacturer publishes more detailed, climate-specific installation standards and maintains a larger trained installer base, it's easier for a contractor to install it correctly and for an inspector to verify it against code — which is a meaningful practical advantage in a county where every roof and wall assembly gets scrutinized for hurricane resistance.
What This Costs You Over Time, Not Just Upfront
Cemplank's modest upfront savings can get erased by long-term maintenance costs if the product isn't factory-finished. A primed fiber cement product needs a quality paint job at installation and repainting on a cycle that's shorter than a ColorPlus factory finish typically requires — and in this climate, that cycle tends to run shorter than in milder regions. When you're budgeting siding, it helps to think in terms of:
- Material and installation cost — the number on the initial quote.
- Finish maintenance cost — repainting cycles, caulking touch-ups, and the labor that comes with both.
- Warranty value — what's actually covered, for how long, and whether it transfers if you sell.
- Resale perception — buyers and their inspectors increasingly recognize the Hardie name and ask about it directly.
When you run those four factors out over a 20-30 year ownership horizon, the gap between Cemplank and Hardie narrows a lot less than the initial quote difference suggests.
A Practical Checklist If You're Comparing Fiber Cement Bids
- Ask whether the product comes with a factory finish or will need field-painting after installation.
- Get the specific warranty document, not just a verbal summary — read the transferability and prorating terms.
- Confirm the product has current Florida Product Approval documentation for your wind zone.
- Ask how many jobs of that specific product your installer has completed in Pinellas County in the last two years.
- Compare clearance and fastening specs the contractor plans to use against the manufacturer's published installation guide.
- Ask what happens if you need a warranty claim in year 12 — who do you call, and does the manufacturer still support that product line?
Why We Only Install James Hardie
We made the decision to standardize on James Hardie because, after installing and maintaining siding on homes across this area, we wanted one product we could stand behind completely — climate-engineered for Gulf Coast conditions, backed by a factory finish system we don't have to gamble on, supported by a warranty that actually holds up and follows the house if it sells, and documented thoroughly enough that we can install it to code with confidence every time. Standardizing on one system also means our crews get deep, repeated experience with its specific installation requirements rather than switching between products and relearning quirks on every job. That's not a knock on every other fiber cement product on the market — it's just where our professional judgment landed after weighing upfront cost against 20-plus years of Florida weather.
If you're weighing Cemplank, Hardie, or another siding option for a home in Largo, we're happy to walk through your specific house, your budget, and what each option would actually mean for your maintenance schedule and long-term costs. Reach out for a free, no-pressure estimate — there's no obligation, and we'll give you a straight answer even if it's not the one you expected.