Twin-wall polycarbonate greenhouses retain 30-40% more heat than single-glazed glass models, making them better for overwintering and early propagation. Horticultural glass (3mm) transmits 90% of light but shatters on impact. Toughened glass (4mm) is five times stronger and breaks into safe granules. Polycarbonate diffuses light evenly, reducing leaf scorch. Budget models start from around 435 pounds for polycarbonate and 549 pounds for toughened glass.
Key takeaways
- Twin-wall polycarbonate retains 30-40% more heat than single-glazed glass
- Horticultural glass transmits 90% of light but breaks into dangerous shards
- Toughened glass is five times stronger than horticultural and shatters safely
- Polycarbonate diffuses light, reducing leaf scorch on tender seedlings
- Polycarbonate greenhouses start from around 435 pounds, toughened glass from 549 pounds
- Glass gives sharper light for fruiting crops; polycarbonate suits propagation and overwintering
greenhouse polycarbonate glass glazing greenhouse buying guide grow your own
Our team produces practical UK gardening guidance from source research, contributor records and established horticultural practice. Editorial standards are overseen by Matt W.
