Windows: your glazing options

Whether you go with double or triple glazing will have an impact on costs, and even on your house construction. Another reason why you need to choose your windows early. 

Double and triple glazing 

In a new build, you will need double or triple glazing.  

Double or IGU – insulated glazing unit. Two sheets of glass separated by a 12mm to 16mm space and hermetically (heat fusion) sealed, is standard. The space may be filled with air or a gas (the most common being argon). The glass can be coated to improve insulation and control solar gain. Wider gaps improve thermal insulation and units are more difficult to break, though they must be pre ordered and can be difficult to fit into existing frames used for double glazing. Having said that, in some cases you can use a thinner edge beading and accommodate a wider double (or even triple) glazed unit into a standard profile. 


Written by Astrid Madsen

Astrid Madsen is the editor of the SelfBuild magazine. She previously held the same role in an Irish trade publication, before that she worked at the National Standards Authority of Ireland. She graduated with a BA in Urban Studies from Columbia University in New York and holds an MBA from the Instituto de Estudios Bursatiles in Madrid. France of origin, she now lives in Portarlington, County Laois, where she's taken on the task of renovating a listed building! Email

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