Which Steel Grating Should You Choose for Singapore Drainage Projects? Our Drainage Gratings Have Been Used in 10+ HDB Projects
Introduction: Every Heavy Rain Is a "Stress Test" for HDB Drainage Systems
Singapore receives nearly 3,000 mm of rainfall annually, with approximately 171 rainy days per year. For HDB (Housing & Development Board) public housing projects, the reliability of drainage systems directly affects the daily safety of millions of residents – ponding on footpaths, flooding in car parks, and difficulties commuting during heavy rain all ultimately come down to the “grating beneath your feet.”
SS 363:2014 is the basic market access requirement for steel grating products in Singapore. For HDB projects, steel grating that does not comply with SS 363:2014 will be directly rejected. HDB certification requires steel grating to pass rigorous verification across three dimensions: material properties, structural design, and safety testing.
Bangtu’s drainage gratings have been successfully used in over 10 HDB projects – from pedestrian footpath drains to multi-storey car park rainwater channels, from tree grates in HDB estates to ventilation covers in public areas. This article systematically analyses which steel grating to choose for HDB drainage projects, based on SS 363:2014 and PUB’s Code of Practice on Surface Water Drainage.
Chapter 1: Three Core Requirements for HDB Drainage Projects
1.1 Load Class – From Footpaths to Carriageways, "Grade by Grade"
HDB projects cover a wide range of scenarios from pedestrian footpaths to multi-storey car parks, and different scenarios require significantly different load ratings for steel grating.
SS 363:2014 adopts the load class classification system consistent with the international standard EN 124:
| Load Class | Test Load | Applicable HDB Scenario | Recommended Type |
|---|---|---|---|
| B125 | 125 kN (12.5 tonnes) | HDB footpaths, green areas, cycle tracks | G325/30/100 |
| C250 | 250 kN (25 tonnes) | Private driveways, light-load areas | G325/30/100S |
| D400 | 400 kN (40 tonnes) | Car park entrances, fire access roads, carriageways | G405/40/150S |
For vehicle traffic areas in HDB multi-storey car parks, D400 class is mandatory, with a test load of 400 kN. For HDB pedestrian footpaths, B125 class is sufficient for daily use.
Selection principle: D400 for carriageways, B125 for footpaths. Do not use B125 on carriageways to save costs – insufficient load capacity will cause grating to deform or even fracture under heavy vehicle loads, creating serious safety hazards.
1.2 Hot‑Dip Galvanized Coating Thickness – 85μm Is the Baseline, 100μm Is the Standard
Singapore’s tropical maritime climate, with high salt spray and high humidity, imposes extremely demanding corrosion resistance requirements on steel grating. HDB requires hot‑dip galvanizing to meet ASTM A123 standards – average coating thickness 85μm, local minimum 70μm. Products that fail to meet these standards are directly rejected at acceptance inspection.
For HDB projects, product thickness typically exceeds 6mm, and the galvanized coating must reach 85μm. Given Singapore’s high salt spray environment, it is recommended to increase the average coating thickness to ≥100μm.
Bangtu’s standard: All HDB-specific drainage gratings have coating thickness ≥100μm, far exceeding the 85μm minimum requirement.
1.3 Slip Resistance Level – The First Line of Defence for Rainy Day Safety
Gratings on HDB footpaths and car parks are directly exposed to the public, making slip resistance a hard requirement for safety acceptance. SS 363:2014 requires slip resistance level ≥ R11 (tested to EN 1090-2).
Serrated steel grating can raise the slip resistance level to R12, maintaining friction resistance above 0.7 even in rainy and wet conditions. For HDB projects with ramps, entrance steps, and wet areas, Type S serrated anti‑slip grating must be used.
Chapter 2: Why Do HDB Projects Choose Our Drainage Gratings?
2.1 Proven Performance Across 10+ HDB Projects
Bangtu’s drainage gratings have been successfully used in over 10 HDB projects, covering the following scenarios:
| HDB Project Type | Application Scenario | Product Used | Number of Projects |
|---|---|---|---|
| HDB pedestrian footpaths | Footpath drainage covers | G325/30/100S | 5+ |
| HDB multi-storey car parks | Rainwater channel covers, carriageway gratings | G405/40/150S | 3+ |
| Community public areas | Tree grates, ventilation covers | G325/30/100S | 2+ |
| HDB ramps | Anti-slip access gratings | G325/30/100S | 2+ |
2.2 Technical Confidence for HDB Certification
Our drainage gratings meet the three core requirements for HDB acceptance:
Load compliance: Full coverage from B125 to D400, meeting different HDB scenario requirements
Coating compliance: Hot‑dip galvanized coating thickness ≥100μm, far exceeding the SS 363:2014 minimum of 85μm, passing 2,000-hour salt spray test with no red rust
Slip resistance compliance: Type S serrated surface, slip resistance level ≥R11, meeting rainy day safety requirements
Chapter 3: Quick Selection Table for Different HDB Scenarios
| HDB Scenario | Load Class | Recommended Type | Slip Resistance Requirement | Coating Thickness |
|---|---|---|---|---|
| HDB footpaths | B125 | G325/30/100S | Type S standard | ≥100μm |
| Community park paths | B125 | G325/30/100S | Type S standard | ≥100μm |
| Private driveways / light-load roads | C250 | G325/30/100S | Type S standard | ≥100μm |
| Car park entrances (vehicular) | D400 | G405/40/150S | Type S standard | ≥100μm |
| Fire access roads | D400 | G405/40/150S | Type S standard | ≥100μm |
| Ramps / steps | Per scenario | G325/30/100S | Type S mandatory | ≥100μm |
| Tree grates / landscape | — | G325/30/100S | — | ≥100μm |
Selection tip: For vehicular traffic areas, D400 is mandatory – do not downgrade to B125 or C250.
Chapter 4: Q&A – Common Questions on HDB Drainage Grating Selection
Q1: What are the specific load class requirements for drainage gratings in HDB projects?
A: According to SS 363:2014 and EN 124, load class requirements for HDB projects depend on the application scenario:
Footpaths, green areas, cycle tracks: B125 class (test load 125 kN)
Private driveways, light-load areas: C250 class (test load 250 kN)
Car park entrances, carriageways, fire access roads: D400 class (test load 400 kN)
For vehicle traffic areas in HDB multi-storey car parks, D400 is mandatory.
Q2: What is HDB's standard for galvanized coating thickness?
A: HDB requires hot‑dip galvanizing to meet ASTM A123 standards – average coating thickness 85μm, local minimum 70μm. For HDB project products with thickness greater than 6mm, the galvanized coating must reach 85μm. Given Singapore’s high salt spray environment, it is recommended to increase the average coating thickness to ≥100μm.
Q3: What tests are conducted on drainage gratings during HDB acceptance?
A: HDB acceptance typically includes verification across three dimensions:
Material properties: Material Test Certificate (MTC), coating thickness testing
Structural design: Load class verification, dimensional tolerance checks
Safety testing: Slip resistance level testing (≥R11), salt spray testing (2,000 hours with no red rust)
Q4: Can we use Chinese standard steel for HDB projects?
A: Yes, but it must pass BC1:2023 certification. Because Chinese GB standard steel is classified as “non‑European standard steel” (alternative structural steel), it must pass BC1 certification to prove equivalency with European standard steel.
Q5: Is there an open area requirement for HDB drainage gratings? How does it affect drainage efficiency?
A: HDB requires steel grating open area ≥40%. Open area directly affects drainage speed – taking G325/30/100 (open area approx. 37%) and G405/40/150 (open area approx. 42%) as examples, the latter has an open area about 13% higher, allowing rainwater to pass through the grating faster during heavy rain, with lower surface runoff and flood risk. For HDB car parks and other areas with high stormwater drainage requirements, it is recommended to prioritise 40mm pitch high‑open‑area products.
Chapter 5: Conclusion and bangtu Company's Technical Commitment
HDB drainage grating selection is never about “which supplier is cheaper” – mismatched load class, inadequate coating thickness, or substandard slip resistance at any point can cause an entire batch of products to be rejected at acceptance inspection, leading to project delays and cost overruns.
Bangtu’s drainage gratings have been successfully used in over 10 HDB projects – from HDB footpaths to multi-storey car parks. Our track record proves:
Load compliance: Full coverage from B125 to D400
Coating compliance: ≥100μm, 2,000‑hour salt spray test with no red rust
Slip resistance compliance: Type S serrated surface, ≥R11 slip resistance level
Dimensional accuracy: Compliant with SS 363:2014 dimensional tolerance requirements
About bangtu Company
Bangtu Company has specialised in the steel grating field for over two decades. Our products are widely used in HDB projects, industrial platforms, petrochemical facilities, marine engineering, and municipal infrastructure in Singapore and globally. For HDB drainage projects, we provide:
Full range of SS 363:2014 compliant drainage gratings: Load classes covering B125 to D400, meeting different HDB scenario requirements
Hot‑dip galvanized coating ≥100μm: Far exceeding the SS 363:2014 minimum of 85μm, passing 2,000‑hour salt spray testing
Type S serrated steel grating: Slip resistance level ≥R11, friction coefficient ≥0.7, meeting rainy day safety requirements
D400 class carriageway gratings: G405/40/150S type, 40×5mm bearing bars, 42% open area – balancing load and drainage efficiency
Matching stainless steel fixing components: Supply stainless steel grating clips, grating clamps, saddle clips for grating, grating fasteners – eliminating galvanic corrosion
Bilingual (Chinese/English) technical documentation: Meeting all documentation requirements for HDB acceptance and BCA certification
View our drainage grating product page for complete specifications and project case studies.
Tel/Whatsapp: +8613363180165
Email: james@bangtuwiremesh.com
Website: www.bangtusteelgrating.com | www.chinawiremesh.ru
