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Overhead Glazing Systems
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A range of overhead glazing bars and roof windows cater for a variety of commercial and residential applications. Bars with a drainage system and condensation collection system are available.

A structurally glazed ThermalHEART roof window for maximum thermal efficiency is available in both opening and fixed options. This is supplied with a 24mm IGU, Argon gas fill and low-e inner pane. A large range of sizes is available, including large expanses for the fixed ThermalHEART window through the use of an added mullion.

Key Features
  • For commercial and residential applications
  • Glazing bars retain glass in sloping positions
  • A range of overhead glazing configurations is possible including lean-to, ridge line, double pitch and pyramid structures
  • Bars with a drainage system and a condensation drainage system are available
  • A glazing cap system for timber rafters is available
  • A non-thermally broken opening roof window can be set within surrounding glazing bars 
  • A thermally broken, ThermalHEART opening roof windows is available
  • Hinged on the lower side the ThermalHEART roof window allows secure opening when required
  • Fixed window option available
  • Structural glazed design means flush edges — no ponding of water allows windows to be installed to low pitches (minimum 5°)
  • Manual or electric opening options
  • ThermalHEART window is capable of dual colour — one colour to match interior schemes and one to match the roof colour;
Scope of Use
  • Suitable for residential and commercial environments
  • Need to be used in defined maximum sizes
Limitations on Use
  • For glazing bar use, sizing will depend on glazing bar choice, wind loadings, span limitations, bar spacing and glass thickness — an engineer’s report may be required 
  • To minimise condensation double glazing is recommended in most applications
  • Minimum pitches apply e.g. ThermalHEART roof window requires minimum 5° pitch
Statement of Building Code Compliance
  • Designed, tested and manufactured to meet NZS 4211: Performance of Windows, and NZS 4233:  Glazing in Buildings, Parts 1-4
  • Designed and tested to conform to NZ Building Code, including Clause E2
In-Service History
  • The glazing bar range was launched in 1997; ThermalHEART roof window in 2008
  • Some design upgrades have taken place
  • Widely used by builders and specifiers
Other Performance Attributes
  • Window and door warranty provided under normal conditions of use against failure of materials and workmanship for a period of five years
  • Surface finish is covered by a separate performance warranty dependent on the actual finish selected
  • A hardware/componentry warranty is offered against defects in manufacturing, functionality and surface finish for a period of five years, provided care and maintenance guidelines have been followed
E2 External Moisture compliant
External Moisture
Data Sheet
Altherm on Masterspec
Specifier Guide: Over Head Glazing
Specifier Guide: Roof Window
WGANZ Guide to E2/AS1
Altherm Care, Maintenance & Warranty Brochure (with AGP)


Altherm Design Brochure


AGP Cleaning & Maintenance
AGP Condensation Guide
AGP Visual Quality of Glass
APL and Sustainability


Manufacturer Contact List
CAD/PDF Details
Full Set of Drawings
Altherm Overhead Glazing Systems A100GB Glazing Bars Fixed Skylight, Small Fin Rafter


Altherm Overhead Glazing Systems A100GB Glazing Bars Fixed Skylight, Small Fin Rafter


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Altherm Overhead Glazing Systems Glazing Bars Double Pitch Roof


Altherm Overhead Glazing Systems Glazing Bars Pyramid Roof


Altherm Overhead Glazing Systems Glazing Bars, Timber Single Glazed


Altherm Roof Window With Thermal Heart


Altherm Fixed Skylight With Thermal Heart


Stylish contemporary lines, effective thermal technology and unwavering attention to detail have made Altherm a favourite with architects, designers and homeowners across New Zealand.

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