The right glazing choice depends on your property type, planning status, thermal goals, and budget. We advise at survey - the answer isn't always the most expensive option.
Single glazing
The period-appropriate option. Required for most Grade I and II listed buildings and many stringent conservation areas. The slimmest profile - critical where glazing bar proportions must match originals exactly.
Heritage
Laminated glazing
Safety glass for positions where Building Regulations require it - ground-floor accessible windows, low-level glazing within 800mm of floor level, and certain door applications. Available as single or double laminated units.
Safety
Double glazing
Standard insulated glass unit. The best price-to-performance ratio where planning permits. Not suitable for most listed buildings or stringent conservation areas - unit thickness alters the sightlines of glazing bars and is often refused.
Performance
Slimline double
A narrower IGU that reduces the visual difference between single and double glazed units. Accepted in many conservation areas where standard double would not be. The default recommendation for most Kensington and Chelsea applications where double glazing is wanted.
Conservation-friendly
Vacuum glazing ✦
Two sheets of glass with a vacuum layer between them - achieving thermal performance comparable to standard double glazing in a unit the same thickness as a single pane. Increasingly accepted by Local Authorities and Historic England for listed buildings and conservation areas where other double glazing options are refused. The highest-cost option, but often the only meaningful thermal upgrade available in planning-sensitive locations.
Premium
