112mm Half Round Rainwater System
Technical Data Sheet
Document Reference: TDS-RW-HR-001
Issue Date: February 2026
System: 112mm Half Round with 68mm Round Downpipe
Product Description
The Kalsi 112mm Half Round rainwater system is a traditional semi-circular profile gutter with matching 68mm round downpipes. This classic design suits virtually any UK property type and remains one of the most popular profiles nationwide. Manufactured from high-quality PVC-U with co-extruded UV-stabilised outer layer for lasting colour retention.
System Dimensions
Gutter
| Dimension | Value | Tolerance |
|---|---|---|
| Profile width (top) | 112mm | ±1mm |
| Profile depth | 55mm | ±1mm |
| Wall thickness | 2.0mm | ±0.2mm |
| Available lengths | 2m, 4m, 5m | ±5mm |
| Weight | 0.54 kg/m | - |
Downpipe
| Dimension | Value | Tolerance |
|---|---|---|
| External diameter | 68mm | ±0.5mm |
| Internal diameter | 61.4mm | ±0.5mm |
| Wall thickness | 3.3mm | ±0.2mm |
| Available lengths | 2.5m, 2.75m, 4m, 5.5m | ±5mm |
| Weight | 0.58 kg/m | - |
Hydraulic Performance
Gutter Flow Capacity
| Gradient | Outlet Position | Flow Rate |
|---|---|---|
| 1:600 | End outlet | 1.52 L/s |
| 1:350 | End outlet | 1.85 L/s |
| Level | Centre outlet | 2.40 L/s |
Downpipe Capacity
| Condition | Flow Rate |
|---|---|
| Full bore | 3.10 L/s |
| 1/3 full (typical) | 1.55 L/s |
Maximum Effective Roof Area
| Rainfall Intensity | Max Roof Area |
|---|---|
| 75mm/hr (standard) | 114m² |
| 100mm/hr (exposed) | 86m² |
| 150mm/hr (high exposure) | 57m² |
Material Specification
| Property | Specification |
|---|---|
| Material | PVC-U (unplasticised polyvinyl chloride) |
| Standard | BS EN 607:2004 |
| Formulation | Lead-free, cadmium-free |
| UV stabilisation | Co-extruded cap layer |
| Colour through | Full body colour |
| Chemical resistance | Resistant to dilute acids/alkalis |
Physical Properties
| Property | Value | Test Method |
|---|---|---|
| Tensile strength | ≥45 MPa | BS EN ISO 527 |
| Impact resistance (23°C) | No fracture | BS EN 607 |
| Impact resistance (-10°C) | No fracture | BS EN 607 |
| Vicat softening temperature | ≥76°C | BS EN ISO 306 |
| Coefficient of expansion | 0.06 mm/m/°C | - |
Colour Options
| Colour | Part Code Suffix | Availability |
|---|---|---|
| White | W | Standard stock |
| Black | BL | Standard stock |
| Brown | BR | Standard stock |
| Grey | G | Standard stock |
| Anthracite Grey | AG | Made to order |
Colours matched across gutter and downpipe components.
Product Range Summary
Gutters
| Description | Part Code | Pack Qty |
|---|---|---|
| 112mm Half Round Gutter 2m | AG2* | 6 |
| 112mm Half Round Gutter 4m | AG4* | 6 |
| 112mm Half Round Gutter 5m | AG5* | 6 |
Angles
| Description | Part Code | Angle | Pack Qty |
|---|---|---|---|
| 90° Gutter Angle | AA1* | 90° | 20 |
| 120° Gutter Angle | AA3* | 120° | 20 |
| 135° Gutter Angle | AA2* | 135° | 20 |
| 150° Gutter Angle | AA4* | 150° | 20 |
Stop Ends
| Description | Part Code | Pack Qty |
|---|---|---|
| External Stop End | AE1* | 100 |
| Internal Stop End | AE2* | 100 |
Outlets
| Description | Part Code | Pack Qty |
|---|---|---|
| Running Outlet | AO1* | 20 |
| Stop End Outlet | AO2* | 20 |
Brackets
| Description | Part Code | Pack Qty |
|---|---|---|
| Fascia Bracket | AK1* | 100 |
| Union Bracket | AU1* | 30 |
| Rise and Fall Bracket | RF/HALF | 1 |
Downpipes
| Description | Part Code | Length | Pack Qty |
|---|---|---|---|
| 68mm Round Downpipe | AP2.5* | 2.5m | 6 |
| 68mm Round Downpipe | AP2.75* | 2.75m | 6 |
| 68mm Round Downpipe | AP4* | 4m | 6 |
| 68mm Round Downpipe | AP5.5* | 5.5m | 6 |
Downpipe Fittings
| Description | Part Code | Spec | Pack Qty |
|---|---|---|---|
| 92.5° Offset Bend | AB1* | 92.5° | 30 |
| 112.5° Offset Bend | AB2* | 112.5° | 30 |
| Pipe Shoe | AB3* | - | 30 |
| Pipe Clip | AC1* | - | 100 |
| Pipe Socket | AS1* | - | 50 |
| Branch 112.5° | AY1* | 112.5° | 20 |
| Hopper | AHS1* | - | 10 |
Adaptors
| Description | Part Code | Pack Qty |
|---|---|---|
| Square/Round Gutter Adaptor | ADS1* | 30 |
| Square to 68mm Round Adaptor | ADS2* | 50 |
| 68mm to 110mm Soil Adaptor | ADS6* | 50 |
Accessories
| Description | Part Code | Pack Qty |
|---|---|---|
| Eaves Protector 1.5m | K/HDEP | 10 |
| Gutter Guard 0.5m | GGUA | 10 |
| Drain Guard | ADGBL | 30 |
Replace * with colour suffix: BL (Black), BR (Brown), W (White), G (Grey), AG (Anthracite Grey)
Installation Guidelines
Gutter Installation
- Maximum bracket spacing: 1000mm (800mm recommended)
- Near joints/fittings: Within 150mm
- Minimum fall: 1:600 (1.5mm per metre)
- Recommended fall: 1:350 (3mm per metre)
- Expansion gap: 10mm at union joints
Downpipe Installation
- Maximum clip spacing: 1800mm (1500mm recommended)
- Near bends/joints: Within 150mm of fitting
- Wall clearance: Minimum 25mm
Thermal Movement
- Allow 6mm expansion per 4m length per 20°C temperature change
- Always use union brackets with expansion gaps
- Do not over-tighten clips
Standards Compliance
- ✓ BS EN 607:2004 - Eaves gutters with fittings of PVC-U
- ✓ BSI Kitemark certified
- ✓ Lead-free and cadmium-free formulation
- ✓ ISO 9001:2015 manufactured
- ✓ 100% UK manufactured
Guarantee
Product Guarantee: 10 years against manufacturing defects
Terms and conditions apply. Registration recommended at www.kalsiplastics.co.uk/support/guarantee-registration
Technical Support
Kalsi Plastics Ltd
Tomey Road, Tyseley
Birmingham B11 2LL
Technical Helpline: [TBC]
Email: info@kalsiplastics.co.uk
Web: www.kalsiplastics.co.uk
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