Double Glazing Specification
A lot of people know they need a sealed unit, but they are not completely sure what specification they actually need. That is where expensive mistakes usually begin. The wrong thickness, the wrong pane make-up, or the wrong assumption about safety glass can leave you with a unit that does not suit the frame, does not meet the job, or needs remaking. The short answer: The right double glazing specification depends on where the unit is being fitted, the required thermal performance, whether safety glass is needed, and the overall thickness the frame can accept. The best choice is rarely the most expensive by default; it is the unit that matches the project’s actual performance and safety needs. The first thing we would check Before anything else, we would check what the unit is going into. Frame allowance matters. Safety requirements matter. Thermal performance matters. You cannot choose the right unit in isolation from the job. If you start with the opening, the frame limits, and the application, the rest of the spec becomes much easier to narrow down. What usually changes the specification The main things that affect the specification are whether safety glass is required, whether low E or better thermal performance is needed, and what overall thickness the frame can accept. That is why we would not automatically push the most expensive option. The right unit is the one that actually suits the application and performs as it needs to. Where people lose money One common mistake is assuming toughened glass is always required in a sealed unit. Another is getting the overall thickness wrong. Both can turn into a remake very quickly because sealed units are bespoke. If the project is at height or within a regulated application, we would always want that checked properly before the order is finalised. How to make the decision properly If you are not sure, work through it in this order: what the unit is for, whether safety glass is needed, what thermal performance matters, and what thickness the frame allows. Once that is clear, pricing the correct unit becomes much more straightforward.