If you’re narrowing your siding options for a St. Louis home, James Hardie and LP SmartSide are almost certainly on your shortlist. Both are premium alternatives to vinyl, both deliver excellent curb appeal, and both are built to outperform in demanding climates. But they’re fundamentally different materials — James Hardie is fiber cement, while LP SmartSide is engineered wood — and those differences matter when you’re making a 30-year decision for your home.
As a St. Louis contractor certified to install both products, here’s an honest comparison based on hundreds of installations across the metro area. The short version: James Hardie wins on longevity and fire resistance; LP SmartSide wins on impact resistance and installation efficiency. Both are excellent choices for St. Louis homes.
James Hardie vs LP SmartSide: Head-to-Head Comparison
| Factor | James Hardie (Fiber Cement) | LP SmartSide (Engineered Wood) |
|---|---|---|
| Cost (installed) | $9.00–$15.00/sq ft | $7.00–$12.00/sq ft |
| Lifespan | 30–50 years | 25–35 years |
| Warranty | 30-year non-prorated | 5/50-year limited |
| Hail resistance | Moderate — can chip | Excellent — flexes on impact |
| Fire resistance | Non-combustible (Class A) | Flame spread ≤25 (treated) |
| Weight | Heavy (~2.5 lbs/sq ft) | Light (~1.2 lbs/sq ft) |
| Moisture resistance | Excellent (HZ10 climate zone) | Good (SmartGuard treatment) |
| Paint adhesion | Good — ColorPlus pre-finish available | Excellent — natural wood texture grips paint |
| Installation time | 7–10 days (typical home) | 5–8 days (typical home) |
| Cutting/workability | Requires specialty tools, generates silica dust | Standard woodworking tools |
What Is James Hardie Fiber Cement Siding?
James Hardie is the dominant fiber cement siding brand in North America. The product is made from Portland cement, sand, and cellulose fibers — essentially a thin concrete board shaped to mimic wood grain, shingles, or smooth panels. Hardie’s HZ10 product line is specifically engineered for St. Louis’s climate zone, where high humidity, freeze-thaw cycling, and temperature swings from single digits to triple digits are all normal.
Key James Hardie products we install:
- HardiePlank lap siding — The most popular profile. Available in Select Cedarmill (wood grain) or Smooth finishes.
- HardieShingle — Staggered edge or straight edge panels for a shingle-style look without the maintenance of real cedar.
- HardiePanel — Large vertical panels for modern or farmhouse aesthetics, popular in St. Louis new construction.
- HardieTrim — Matching trim boards that complete the system. Critical for a clean, finished installation.
Meridian is a James Hardie Elite Preferred installer, one of a limited number of certified contractors in the St. Louis market. This certification means our crews are factory-trained on Hardie’s specific installation methods, and our work qualifies for Hardie’s full 30-year non-prorated warranty.
What Is LP SmartSide Engineered Wood Siding?
LP SmartSide is made from wood strands bonded with resin and wax, then treated with LP’s proprietary SmartGuard process — a zinc borate treatment that provides deep, lasting protection against fungal decay and termites. The result is an engineered wood product that looks and works like real wood but resists the problems that make natural wood siding a maintenance headache.
Key LP SmartSide products we install:
- Lap siding — Available in smooth, cedar texture, and brushed finishes. The cedar texture is the most popular in St. Louis.
- Panel siding — 4×8 and 4×9 panels for vertical or modern applications.
- Shakes — Cedar-texture shake panels that install faster than individual shakes while delivering the same aesthetic.
- Trim and fascia — Matching trim products for a complete system.
LP SmartSide’s biggest selling point for St. Louis homeowners is its impact resistance. In our hail-prone market — where damaging storms hit nearly every spring between March and June — this matters. LP SmartSide flexes on impact rather than cracking or chipping, and the 5/50-year warranty includes coverage for hail damage.
Which Siding Handles St. Louis Weather Better?
St. Louis throws everything at your siding: 90°F+ summer heat with high humidity, winter lows in the single digits, 40+ inches of annual rainfall, and regular hailstorms from March through September. Both products handle this climate well, but each has different strengths.
Humidity and Moisture
James Hardie’s HZ10 formula is specifically designed for humid climates. Fiber cement doesn’t absorb moisture the way traditional wood does, which means no warping, swelling, or rot. LP SmartSide’s SmartGuard treatment protects against moisture damage, but engineered wood is inherently more moisture-sensitive than fiber cement. Proper flashing, house wrap, and caulking are critical with LP SmartSide — though that’s true of any siding installation done right.
Hail and Impact
This is where LP SmartSide has a clear advantage. Fiber cement is rigid — hailstones can chip the surface, especially on older paint. LP SmartSide’s wood-strand construction absorbs and distributes impact energy, so hailstones bounce off rather than leaving marks. For homes in high-exposure areas (no tree cover, south/west facing walls), this is a real consideration.
Freeze-Thaw Cycling
Both products handle St. Louis’s 50+ annual freeze-thaw cycles well. James Hardie’s HZ10 uses a proprietary moisture-management technology that reduces water absorption before freezing — the main cause of cracking in fiber cement. LP SmartSide’s flexibility gives it a natural advantage against thermal expansion and contraction stress.
Cost Comparison: James Hardie vs LP SmartSide in St. Louis
LP SmartSide typically costs 15–25% less than James Hardie for a comparable installation. On a typical 1,800-square-foot St. Louis home, that translates to a $3,000–$6,000 difference.
| Project Size | James Hardie (Installed) | LP SmartSide (Installed) | Savings with LP |
|---|---|---|---|
| Small home (1,200 sq ft) | $10,800–$18,000 | $8,400–$14,400 | $2,400–$3,600 |
| Average home (1,800 sq ft) | $16,200–$27,000 | $12,600–$21,600 | $3,600–$5,400 |
| Large home (2,500 sq ft) | $22,500–$37,500 | $17,500–$30,000 | $5,000–$7,500 |
The cost difference comes from two sources: LP SmartSide materials are less expensive per square foot, and the lighter weight/easier workability means faster installation — which reduces labor hours. For a detailed breakdown of all siding material costs in St. Louis, see our 2026 siding replacement cost guide.
Which Should You Choose?
There’s no universal winner. The right choice depends on your specific situation:
Choose James Hardie if:
- You want maximum lifespan (30–50 years)
- Fire resistance is a priority (attached garage, close-neighbor lots)
- You prefer the ColorPlus factory-finish option (15-year paint warranty)
- You’re planning to stay in the home long-term and want the lowest lifetime cost
Choose LP SmartSide if:
- Hail resistance matters (exposed walls, no tree cover)
- Budget is a primary factor (15–25% lower installed cost)
- You want a natural wood-grain texture that holds paint exceptionally well
- Your home has complex geometry where lighter, more workable material reduces labor cost
Both products are dramatically better than vinyl siding in terms of durability, appearance, and long-term value. If you’re upgrading from vinyl, either choice is a significant improvement.
Get a Free Siding Consultation
Meridian installs both James Hardie and LP SmartSide — we’re not locked into one brand, so our recommendation is based on what’s right for your home, not what’s in our warehouse. We’ll inspect your home, assess your exposure to hail and moisture, and give you an honest comparison with itemized pricing for both options.
Call us at 314-952-4158 or request your free siding consultation online.
James Hardie vs LP SmartSide FAQs
Which siding is better for hail-prone areas like St. Louis?
LP SmartSide is better for hail resistance. Its engineered wood construction flexes on impact, while James Hardie fiber cement can chip from hailstones. LP SmartSide’s warranty also includes hail damage coverage. For homes with high exposure to storms, LP SmartSide has a clear edge.
Does James Hardie or LP SmartSide last longer?
James Hardie typically lasts longer — 30 to 50 years compared to LP SmartSide’s 25 to 35 years. Fiber cement is inherently more durable against moisture and UV exposure over decades. However, both products far outlast vinyl siding’s 20 to 30 year lifespan.
Is LP SmartSide cheaper than James Hardie?
Yes. LP SmartSide costs 15–25% less than James Hardie installed. On a typical 1,800-square-foot St. Louis home, that’s $3,000–$6,000 in savings. The difference comes from lower material costs and faster installation due to LP SmartSide’s lighter weight.
Can you mix James Hardie and LP SmartSide on the same house?
Yes, and some homeowners do. A common approach is using James Hardie on the main body and LP SmartSide shakes or panels as accents. Both products accept paint equally well, so color matching is straightforward. However, mixing materials adds complexity to the installation and may affect warranty coverage, so discuss this with your contractor first.
Which siding has a better warranty?
James Hardie offers a 30-year non-prorated warranty, meaning the full replacement cost is covered for the entire term. LP SmartSide has a 5/50-year limited warranty — 5 years on defects and 50 years prorated on substrate failure. For raw warranty strength, James Hardie’s non-prorated coverage is stronger.
