1. PVC Foam Board vs Solid Board Basics
In engineering plastics procurement, PVC foam board and solid PVC board (rigid PVC board) look similar but differ greatly in internal structure and performance. Many buyers, unfamiliar with the differences, encounter issues like "bought foam when solid was needed—strength insufficient" or "bought solid when foam was needed—weight exceeded and cost overran." This article systematically compares the two for correct selection.
1.1 What Is PVC Foam Board
PVC foam board is made primarily from PVC resin with foaming agents, stabilizers, and modifiers, formed by free-foaming or Celuka process into a micro-cellular structure. It contains many closed-cell bubbles, with density only 1/3 to 1/2 that of solid board, combining light weight, water resistance, sound insulation, and easy processing. It is widely used in advertising, furniture, and building formwork.
1.2 What Is Solid PVC Board
Solid PVC board is the traditional rigid PVC board (UPVC), produced by extrusion or calendering into a dense solid structure with density 1.38-1.45 g/cm³. It features high strength, corrosion resistance, flame retardancy, and excellent electrical insulation, mainly used in chemical corrosion protection, electroplating tanks, ducts, and electrical insulating parts.
2. Five Performance Differences
2.1 Density and Weight
| Property | PVC Foam | Solid PVC |
|---|---|---|
| Density (g/cm³) | 0.5-0.7 (Celuka) / 0.3-0.5 (free foam) | 1.38-1.45 |
| Same-area weight | 1/2 to 1/3 | 1 (baseline) |
| Internal structure | Closed-cell micro-foam | Dense solid |
PVC foam board is only 1/3-1/2 the density of solid, weighing 50%-65% less at equal thickness—a major advantage for weight-sensitive scenarios (marine interiors, prefab houses).
2.2 Mechanical Strength and Impact
| Property | PVC Foam | Solid PVC |
|---|---|---|
| Tensile strength | 15-25MPa | 50-60MPa |
| Flexural strength | 20-30MPa | 80-100MPa |
| Notched impact | 8-15kJ/m² | 5-8kJ/m² |
| Shore hardness | D50-D70 | D85-D90 |
Solid board has 3x the tensile and flexural strength, better for load-bearing; foam has slightly higher impact strength, less brittle, but lower surface hardness and easier to scratch.
2.3 Water Absorption and Weathering
| Property | PVC Foam | Solid PVC |
|---|---|---|
| Water absorption (24h) | ≤1.0% | ≤0.05% |
| Moisture resistance | Good (better for Celuka) | Excellent |
| Outdoor life | 3-5 years (UV-modified) | 5-10 years |
Both resist moisture, but solid is almost non-absorbent, better for long-term immersion. Foam surfaces with skin are good; free-foam cross-sections absorb moisture and require UV treatment outdoors.
2.4 Processability
| Property | PVC Foam | Solid PVC |
|---|---|---|
| Cutting | Wood saw, laser, CNC all OK | Requires special blades; high tool wear |
| Drilling/nailing | Easy; self-tapping OK | Cracks easily; pre-drill needed |
| Surface | Paint, silk screen, laminate possible | Hard to paint; special ink required |
| Hot bending | Possible, controlled temp | Possible, higher temp, narrow window |
PVC foam board processes like wood—an ideal wood substitute; solid is harder and demanding on tools.
2.5 Price and Value
| Thickness | PVC Foam (RMB/m²) | Solid PVC (RMB/m²) |
|---|---|---|
| 3mm | 35-55 | 40-60 |
| 5mm | 60-90 | 80-120 |
| 10mm | 100-160 | 160-220 |
| 15mm | 160-240 | 240-320 |
| 20mm | 220-320 | 320-420 |
At equal thickness PVC foam is 20%-30% cheaper. But solid is much stronger, allowing thinner specs at equal load—total cost may be lower.
3. Application Comparison
3.1 Advertising Signage
- PVC foam: outdoor signage, displays, 3D letters, light box panels (light, easy, printable)
- Solid PVC: chemical light boxes, corrosion signs
3.2 Furniture, Cabinetry, Bath
- PVC foam: cabinet doors, bathroom cabinets, wardrobe partitions (waterproof, wood-like)
- Solid PVC: lab benches, chemical storage cabinets (corrosion-resistant, strong)
3.3 Chemical and Electroplating
- PVC foam: not suitable
- Solid PVC: electroplating tank lining, acid tanks, ducts, chemical lining (preferred)
3.4 Building Formwork and Decoration
- PVC foam: concrete formwork, partitions, decorative moldings (nailable, planable, wood-like)
- Solid PVC: waterproof membranes, anti-corrosion flooring, electrical raceways
3.5 Marine and Rail Transit
- PVC foam: cabin interiors, partition panels (weight saving)
- Solid PVC: chemical tanker cargo lining, duct systems
4. Five-Step Selection Decision
- Load requirement: high load → solid; low load → foam
- Corrosion environment: strong corrosion → solid; moisture only → foam
- Weight requirement: weight saving → foam; rigidity → solid
- Processing: paint/print/nail → foam; weld → solid
- Budget: equal thickness foam cheaper; equal strength recalculate
As a professional engineering plastics supplier, huagong offers PVC foam and solid PVC in multiple specs and brands with cutting, hot bending, and welding services. Contact us for quotes.
5. FAQ
Q1: Which is more expensive, PVC foam or solid?
At equal thickness PVC foam is 20%-30% cheaper. But solid is 3x stronger; at equal load, solid can use thinner specs, so total cost may be lower.
Q2: Can PVC foam be used outdoors?
Yes, but only UV-modified grades; otherwise yellows and embrittles within 1-2 years. Outdoor life 3-5 years; long-term outdoor prefers solid or PC.
Q3: What temperature can PVC foam withstand?
Long-term ≤60°C, same as solid; instantaneous ≤80°C; deforms above Vicat. High-temperature scenarios use CPVC or PC.
Q4: Can PVC foam and solid be welded?
Solid can be hot-air and hot-plate welded with strong seams; PVC foam has cellular structure, weak welds—use adhesive or mechanical joints.
Q5: Does PVC foam have environmental requirements?
EU exports require RoHS and REACH; interior decoration requires GB 18586. Quality PVC foam uses lead-free stabilizers.
6. Summary and Action
Although both belong to the PVC family, foam and solid boards differ significantly in density, strength, water absorption, processability, and price due to structural differences. Before purchase, clarify load, corrosion, weight, processing, and budget, then match against foam vs solid characteristics to select technically compliant and cost-effective material.
For detailed spec sheets, comparison reports, or the latest quotes on PVC foam or solid PVC, contact huagong—our engineering plastics team provides professional selection support.
Related:
- Browse the Engineering Plastics Center for PVC foam, solid, and PVDF specs
- Read PVC Board Specifications and Prices for PVC sheet specs
- Contact huagong for cutting, welding, and hot bending services