Glass blowing
Stained Glass Windows: Managing Environmental Deterioration, published by Historic England in 2020, suggests that glass blowing is a: ‘Glass-forming technique, probably developed in Babylonia and the Middle East by the 1st century BC. Molten glass is gathered into a ball on the end of a hollow pipe, and rolled on an iron former to roughly shape it and to slightly cool the surface. Then the pipe is used to blow air into the glass and form it into a bubble. By repeated blowing, shaping and reheating, the glass can be formed in many ways.’
Archaeological Evidence for Glassworking, Guidelines for Recovering, Analysing and Interpreting Evidence, published by Historic England in 2018, defines a blowing iron as: ‘A long iron tube that was dipped into the molten glass to collect a gather for subsequent inflating and shaping.’
It defines optic blowing as a process in which: 'A gather of glass is blown into a mould with a pattern on the inner surface, which transfers to the glass. Continued free blowing results in movement and distortion of the pattern.'
And overblow as: 'A by-product of mould blowing, referring to the glass that remains outside the mould, which is removed and recycled.'
It defines paraison as: 'The partially inflated gather of glass at the end of the blowing iron.'
And paraison end as: 'A marble-shaped blob of glass pinched from the end of the gather during the blowing of particular forms, such as the bowls of goblets.'
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Future Homes Standard Essentials launched
Future Homes Hub launches new campaign to help the homebuilding sector prepare for the implementation of new building standards.
Building Safety recap February, 2026
Our regular run-down of key building safety related events of the month.
Planning reform: draft NPPF and industry responses.
Last chance to comment on proposed changes to the NPPF.
A Regency palace of colour and sensation. Book review.
Delayed, derailed and devalued
How the UK’s planning crisis is undermining British manufacturing.
How much does it cost to build a house?
A brief run down of key considerations from a London based practice.
The need for a National construction careers campaign
Highlighted by CIOB to cut unemployment, reduce skills gap and deliver on housing and infrastructure ambitions.
AI-Driven automation; reducing time, enhancing compliance
Sustainability; not just compliance but rethinking design, material selection, and the supply chains to support them.
Climate Resilience and Adaptation In the Built Environment
New CIOB Technical Information Sheet by Colin Booth, Professor of Smart and Sustainable Infrastructure.
Turning Enquiries into Profitable Construction Projects
Founder of Develop Coaching and author of Building Your Future; Greg Wilkes shares his insights.
IHBC Signpost: Poetry from concrete
Scotland’s fascinating historic concrete and brutalist architecture with the Engine Shed.
Demonstrating that apprenticeships work for business, people and Scotland’s economy.
Scottish parents prioritise construction and apprenticeships
CIOB data released for Scottish Apprenticeship Week shows construction as top potential career path.
From a Green to a White Paper and the proposal of a General Safety Requirement for construction products.
Creativity, conservation and craft at Barley Studio. Book review.
The challenge as PFI agreements come to an end
How construction deals with inherited assets built under long-term contracts.
Skills plan for engineering and building services
Comprehensive industry report highlights persistent skills challenges across the sector.
Choosing the right design team for a D&B Contract
An architect explains the nature and needs of working within this common procurement route.
Statement from the Interim Chief Construction Advisor
Thouria Istephan; Architect and inquiry panel member outlines ongoing work, priorities and next steps.