Blog6 min read
Glass railings for accessible roofs: what matters
SP 31-110 public-space calc, wind loads at 20+ m, real cases of business centres and penthouses.
An accessible roof on a business centre or penthouse is a public space under SP 31-110 (1 kN/m line load) or a high-wind residential zone. Standard balcony specs don't apply here.
01Design loads
| Param | Residential (balcony) | BC roof |
|---|---|---|
| Horizontal line load | 0.36 kN/m | 1.0 kN/m |
| Point load | 0.5 kN | 1.5 kN |
| Wind at 20+ m | 0.6 kN/m² | 1.2 kN/m² |
| Min height | 900 mm | 1100 mm |
Practically: 8+8 PVB or 10+10 instead of residential 6+6.
022026 prices for typical BC roof
| Length | Spider 8+8 PVB | + wood handrail |
|---|---|---|
| 20 lin.m | from 488 000 ₽ | from 624 000 ₽ |
| 50 lin.m | from 1.22M ₽ | from 1.56M ₽ |
| 100 lin.m | from 2.44M ₽ | from 3.12M ₽ |
| + A4 marine stainless | +22% | +22% |
A BC roof isn't a balcony. Manifold higher cost, different engineering, stricter codes. Clients try to save with "residential" specs — but inspection requires SP 31-110 calc. Budget from 25 000 ₽/lin.m.
03This service at REAL GLASS
If you've read this far, the topic is probably relevant to a real project. We make glass railings in-house in St. Petersburg, with a measure within 1–3 days, 1-year warranty and a fixed contract price. All numbers in this article come from our actual 2026 quotes.
For a project-specific estimate — see the service page or request a free on-site measure.
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