Patent Glazing & Roof Lights Quotes
Quick Guide to Products
Which system to use?

Unheated Spaces, canopies, station and platform glazing SkyGard should be your first choice if using 6 to 7mm thick glass. If considering different glass thickness, then PlasGard would be your next choice

Heated Spaces
ThermGard is our thermally broken system providing excellent Uvalues and air-tightness when combined with insulating double glazed units for compliance with Building Regulations Part L.

Self-supporting Lanterns or SkyLights
SpanGard self-supporting rooflights feature extruded cill, ridge & hip members to provide you with a complete kit pre-fabricated upto 6m wide by infinite length without the need for additional support, other than a load-bearing curb.

If using Polycarbonate
PlasGard offers a range of glazing bars & accessories for use with ‘plastic’ glazing materials for unheated spaces. If you require a thermally broken system, then please see our ThermGard ALM500 Series

Rafter Glazing
If fitting glazing bars on top of continuous timber rafters, then section reference ALM100/WF suitable for single or double glazing from our ThermGard range, provides neat, low-profile appearance combined with excellent weather tightness and low-maintenance.

Need ventilation?
GlazaTherm roof vents can be incorporated in sloped glazing and fitted with manual, electric or smoke actuators. Alternatively we can provide casement vents in the upstands of lantern lights when required.
Consult the experts
Tel: +44(0)208 801 4221
Bomb-blast Mitigation
Safety Condensation
Glass Types Fire
Glazing Bar Centres Cleaning & Maintenance
Glazing Bar Spans CDM Non-Fragility
Structural Considerations Energy & Environment
Structural Tolerances Design Life Durability
Marine Environment  

Glazing Bar Centres

Traditionally patent glazing was always installed at 241/2” centre bar to centre bar spacings as a 24” wide pane of glass was easy to handle and can fit under-arm enabling relatively long pieces of glass to be man-handled into position by one fixer. Another reason was that there was not the great variety of glass types as there are today and simple wired glass was manufactured in stock sheets 48” wide – cut one in half and you had no waste! Today patent glazing bars tend to be installed at ‘nominal 600mm centres’. At this width handling remains relatively simple and hence the cost of installation remains as low as possible. Wider spacings can be achieved, although at Lonsdale we tend not to recommend the use of two-edge support systems beyond 750mm as a rule of thumb. In some circumstances, spacings can be increased upto 900-1200mm, but this requires special consideration of all the site conditions. Wider glass, particularly double glazed units are more difficult to handle and it is important installation aspects be considered as due to weight and size, additional labour and equipment may be required thus adding to the cost. Please speak with Technical Support for advice.