Repair Systems — Roofing Defects — Gutter Replacement
Half-round gutter systems for residential and heritage roof replacement
Half-round gutters are widely used in heritage, Californian bungalow and Federation-style buildings as well as modern architectural applications due to their smooth internal profile and self-cleaning characteristics. Lysaght, Stramit and Stratco half-round gutters are available in Colorbond and Zincalume, with heritage copper options available for conservation-grade works.
What are half-round gutter systems?
Half-round gutters are widely used in heritage, Californian bungalow and Federation-style buildings as well as modern architectural applications due to their smooth internal profile and self-cleaning characteristics. Lysaght, Stramit and Stratco half-round gutters are available in Colorbond and Zincalume, with heritage copper options available for conservation-grade works.
Product Reference
3 products — Lysaght, Stramit, Stratco — half-round gutter systems — scroll to view all
Lysaght Half-Round Gutter
Colorbond/Zincalume half-round gutter — 100mm and 125mm — heritage compatible
System Description
Lysaght Half-Round Gutter is available in Colorbond and Zincalume steel in 100mm and 125mm sizes with 6m standard lengths. The half-round profile is characterised by its smooth semicircular internal surface, which provides self-cleaning flow characteristics and a traditional aesthetic suited to heritage, Californian bungalow and Federation-style buildings. Lysaght's heritage-compatible profiles are specifically relevant on older-style buildings where the half-round profile must match the existing gutter form for aesthetic or heritage council compliance reasons. The complete fittings range includes half-round outlets, end caps, and angle sections. Colorbond finishes are available in the current colour range — Zincalume provides additional corrosion resistance for coastal and marine environments. Confirm the current product range, heritage profile availability, and Colorbond colour options with Lysaght or your local roofing supplier before ordering. All replacement works must comply with AS/NZS 3500.3.
Technical Properties
- Half-round profile in Colorbond or Zincalume steel — 100mm and 125mm sizes — 6m lengths
- Smooth semicircular internal surface — self-cleaning flow characteristics — reduced debris accumulation
- Heritage-compatible profiles — suited to older-style, Californian bungalow and Federation buildings
Limitations
- Not suitable for box gutter applications — external eave gutter only
- Gutter sizing must be confirmed against rainfall intensity zones per AS/NZS 3500.3 — hydraulic capacity of half-round is different from quad of the same nominal size
- Heritage profile availability — confirm current stock and lead times with Lysaght before specifying on a heritage project with tight programme requirements
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Stramit Half-Round Gutter
Colorbond steel half-round gutter — 100mm, 125mm and 150mm
System Description
Stramit Half-Round Gutter is formed from BlueScope Colorbond steel and is available in 100mm, 125mm, and 150mm sizes — the largest standard size range offered by the major suppliers. The 150mm half-round size provides significant hydraulic capacity for larger catchment areas on residential and light commercial buildings. Stramit's full fittings range includes half-round angles, joiners, stop ends, and downpipe outlets for a complete installation without site fabrication. Available nationally through Stramit branches and trade roofing suppliers. Confirm the current product range, available Colorbond colours, and stock availability with your local Stramit branch before ordering. All replacement works must comply with AS/NZS 3500.3.
Technical Properties
- Half-round profile in BlueScope Colorbond steel — 100mm, 125mm, and 150mm sizes
- 150mm size provides extended hydraulic capacity for larger roof catchment areas
- Full fittings range: angles, joiners, stop ends, and half-round downpipe outlets
Limitations
- Not suitable for box gutter applications — external eave gutter only
- Gutter sizing must be confirmed against rainfall intensity zones per AS/NZS 3500.3
- Minimum fall of 1:500 must be verified in the existing fascia line before replacement
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Stratco Half-Round Gutter
Colorbond steel half-round gutter — 100mm to 150mm — full Colorbond colour range
System Description
Stratco Half-Round Gutter is available in Colorbond steel from 100mm to 150mm sizes with a complete range of bracket, outlet, and end cap fittings. The Stratco system is available in all current Colorbond colours through Stratco trade centres nationally. Stratco's comprehensive distribution network and in-store fittings range make it a practical choice for re-guttering works where colour matching to existing roofing and fascia is important. Confirm the current product range, available sizes at your local Stratco trade centre, and Colorbond colour availability before ordering. All replacement works must comply with AS/NZS 3500.3.
Technical Properties
- Half-round profile in Colorbond steel — 100mm to 150mm sizes — available nationally through Stratco trade centres
- Complete fittings range: brackets, outlets, end caps, angles, and joiners — co-ordinated fittings supply
- Available in all current Colorbond colours — practical for colour-matched re-guttering with existing roofing
Limitations
- Not suitable for box gutter applications — external eave gutter only
- Gutter sizing must be confirmed against rainfall intensity zones per AS/NZS 3500.3
- Minimum fall of 1:500 must be verified in the existing fascia line before replacement
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of half-round gutter systems. All three brands supply Colorbond half-round gutters in equivalent sizing — Lysaght offers heritage-specific profiles for older-style building applications.
| Brand | Sizes | Material | Heritage suitability |
|---|---|---|---|
| Lysaght | 100mm, 125mm | Colorbond / Zincalume steel | Yes — heritage-compatible profiles available |
| Stramit | 100mm, 125mm, 150mm | Colorbond steel (BlueScope) | Standard residential and light commercial — confirm heritage profile with supplier |
| Stratco | 100mm to 150mm | Colorbond steel | Full colour range — confirm heritage profile availability with Stratco |
Brand Equivalence Note
Lysaght ≈ Stramit ≈ Stratco— all offer Colorbond half-round gutters in equivalent sizing suitable for residential and strata re-guttering. Lysaght heritage profiles are specific to older-style building applications where profile geometry must match the original gutter form. Product selection is typically driven by the roofing contractor's supplier relationship and local stock availability.
Do not confuse half-round gutter replacement with:
- Quad (ogee) gutters — different profile shape — listed on the quad gutter systems page — fittings are not interchangeable between quad and half-round
- Box gutters — custom-fabricated internal gutters on multi-storey buildings — not the same as external eave gutters — listed on the box gutter systems page
- Copper half-round gutters — a separate product category requiring specialist heritage supply — must not be mixed with Colorbond or ferrous metal components due to galvanic corrosion risk
- Gutter lining systems — proprietary relining products applied inside existing gutters rather than replacing them
- Fascia replacement — gutter replacement does not automatically include fascia board repair or replacement — assess fascia condition separately before specifying
Disclaimer
This page provides general technical information only. Final product selection must be confirmed against the current manufacturer technical data sheet, project specification, existing fascia condition, required gutter fall, heritage council requirements where applicable, rainfall intensity zone per AS/NZS 3500.3, and contractor supply relationships. Do not rely on this reference as a substitute for professional engineering or building consultant advice.