Hardwood orangery in Berkhamsted


Timber Roof Lantern Drawings and Details


Download PDFs here:

Full Drawing Set set

Standard Cross Section

45 x 95 rafter with 24mm double-glazing

45 x 95 rafter with 36mm triple-glazing

Lantern on windows

Stepped Glass Cross Section



Timber Lantern

This is our standard section, non-stepped double-glazed units.

A typical upstand is around 85mm wide, but we can accommodate any thickness if we know in advance. Building Regulations stipulate that the upstand should be 150mm high.

In situations where the available height is limited due to planning restrictions, we can design a lantern where the flat roof covering can be run up the outside of the lantern.



Hardwood orangery in Berkhamsted

The rafters are typically 45mm x 95mm with 24mm double-glazed units.

Depending on the span and design, hip rafters may be slightly deeper than this. A concealed cable groove can be factory-fitted into a specified rafter to hid the. cables for any electrical roof vents or central lighting.






timber lantern

Cross Section of Lantern on Windows

The side windows are made to measure, however a height of less than 300mm is generally not recommended. Whilst it is feasible to fit opening vertical windows, an opening roof window is a more effective and aesthetically pleasing option.




Hardwood orangery in Berkhamsted


36mm triple-glazed option

The difference between double and triple glazing in terms of thermal performance isn’t as great as many people expect,  but in some situations it’s important to gain every possible advantage.






timber lantern

Glass units with a 70mm step to top sheet for a more traditional look

Some clients prefer the look of stepped glass units.