Are there glazing guidelines?

Yes, please see the Literature tab. Pilkington Spacia™ at 6.5 mm is slimmer than conventional units which means there are more glazing options and opportunities.


Can I see a sample?

Yes, samples are available however, since they are rather expensive, we ask for details about your project. The best way to obtain one is to email us via our Contact form


Can it be made to any size or shape?

Many shapes can be produced, but to do so two straight edges forming a right angle are required. Please see the examples below.

The size limits are: 

Maximum 1350 x 2400mm Clear
Maximum 1200 x 1800mm Sandblasted
Minimum 200 x 350mm


Can it be used to comply with building regulation document N - low level glazing?

Pilkington Spacia™ is not an impact-resistant glass classified to BS EN 12600. It can however have a film applied or be modified on site to achieve the required classification.


Can it be used to comply with current building regulations concerning energy efficiency?

Yes. As part of a SAP calculation for new buildings Pilkington Spacia™, in an appropriate frame, can meet or improve upon the limit window U-value or 2.0 W/m²K. Pilkington Spacia™ can also be used for replacement windows that require a WER (Window Energy Rating) of band C or above or a window U-value of, at worse, 1.6 W/m²K. Certain buildings that are restricted in their glazing options have special consideration for energy efficiency. They can benefit from using Pilkington Spacia™ where traditional glazing is inappropriate and single glazing does not provide the thermal comfort of a modern home.


Can Pilkington Spacia™ be putty glazed?

Yes. It is compatible with most glazing compounds with the exception of those containing acetic acid.


Can you see the spacer bar?

Pilkington Spacia™ vacuum glazing doesn’t use spacer bar technology, and therefore can be easily glazed into steel, wood and secondary glazing window systems, both new or old with the same visual appearance as single glazing.


Does the product come with a warranty?

Yes. The standard warranty is 10 years.


How do you stop the 2 panes of glass touching each other?

There is a grid of micro spacers within the unit keeping the glass surfaces apart. They are 0.5mm diameter and 20mm apart, and when viewed in transmission at a distance of 1-2 meters they become imperceptible.


How does the performance of the product compare with other Pilkington low-e products?

Pilkington Spacia™ is far from a compromise on performance. Just compare the figures in this table, which shows that it is four times more thermally efficient than single glazing. 

Product Nominal thickness (mm) Light Transmittance  Light Reflectance  Centre Pane Ug-value [W/m²K] Solar Total Solar Heat Transmittance (g-value)
Direct Transmittance  Reflectance 
Single Glazing
6 mm Pilkington Spacia™ 6.2 0.78 0.13 1.1 0.62 0.17 0.67
6 mm Pilkington Spacia™ Cool 6.2 0.70 0.23 0.9 0.48 0.34 0.53
Traditional Glazing options
4 mm Pilkington Optifloat™ Clear 4 0.90 0.08 5.8 0.85 0.08 0.87
4 mm Pilkington Optifloat™ Clear
/ 16 mm air /
4 mm Pilkington K Glass™
24 0.75 0.18 1.7 0.62 0.16 0.73

Max size: 2400 mm × 1500 mm. Min size: 335 mm × 120 mm. Pilkington Spacia™ Opaque max size: 1800 mm × 1200 mm.
The above table is determined in general accordance with EN 410 and EN 673 with the exception of the U value for Pilkington Spacia™ which has been measured in accordance with EN 674.


How long does it take from placing and order to delivery?

The standard lead time is 12-14 weeks; a 4-5 week delivery is available via air freight but this does obviously increase the cost considerably.


Is there an obscure version?

Yes there is a sandblasted version with the obscure facing into the cavity. The maximum size is 1800 x 1200 mm and the obscure version is currently the same price as the clear version.


Tell me about the air extraction point

Pilkington Spacia™ uses vacuum technology and the point at which air is removed is covered by a small cap on every unit. The black protection cap is 12mm in diameter and set 50mm in from two edges of the glass and should not be removed.  The cap is not intrusive and tends not to be noticed once glazed. Although the cap comes in black as standard, silver is also available on request.


What will it cost?

The price is available on application. There is a minimum area charge 0.3m² per pane. For orders above 4m², and as an approximate guide the cost will fall between £200 - £300m² depending upon volume, sizes and quantities, as packaging and delivery costs need to be included. Please contact the Pilkington Spacia™ dealerships with any enquiry as these costs can vary. Note - the smaller the order the more expensive the glass per m², as small orders attract a disproportionate level of transport costs


What acoustic performance does this product provide?

A comparison of the sound insulation data of Pilkington Spacia™ compared to that of single and double glazing is provided in the table below: 

Product Rw (C; Ctr) dB  Improvement due to Pilkington Spacia™ (dB) 
6.2 mm Pilkington Spacia™ 35 (-1; -3) N/A
Single glazing 
4 mm Float Glass 29 (-2; -3) +6
6 mm Float Glass 31 (-2; -3) +4
8 mm Float Glass 32 (-2; -3) +3
10 mm Float Glass 33 (-2; -3) +2
12 mm Float Glass 34 (0; -2) +1
Double glazing
4 mm Pilkington Optifloat™ - 16 mm argon - 4 mm Pilkington Optifloat™ 31 (-2; -5) +4
6 mm Pilkington Optifloat™ - 16 mm argon - 4 mm Pilkington Optifloat™ 34 (-2; -5) +1

Note: The values for single glazing are generally accepted values for generic products taken from EN 12758. They are conservative values that can be used in the absence of measured data. The values for Pilkington Spacia™ and insulating glass units have been measured in accordance with EN ISO 10140 and Rw (C; Ctr) determined in accordance with EN ISO 717-1.