Technical Specification

The Technical Information Explained. Noise reduction, thermal insulation and more.

InvisiTherm™ Polycarbonate

InvisiTherm™ bespoke magnetic secondary glazing system uses a robust intelligent transparent polycarbonate.  This top-grade polycarbonate has outstanding thermal properties which can reduce the heat loss through the glaze by as much as 63%. We are so confident our magnetic secondary glazing system will stay clear to the naked eye, that we give all our customers a 10 year guarantee. 

How thick is the polycarbonate sheet?   It is 4mm thick as our tests show that this is the optimum thickness.

Why don't we use acrylic or perspex?  Polycarbonate is much stronger and around 30 times the impact strength of acrylic or perspex. The unique polycarbonate that we use in our magnetic secondary glazing is also fire rated, ensuring no risk to customer safety and well-being.  We can also cut InvisiTherm™ into any angle required.
Email now to receive your free InvisiTherm technical brochure

     Glaze & Save system uses a robust intelligent transparent polycarbonate called InvisiTherm™. The properties of this are:
magnetic secondary glazing solutions,
  • We use the latest technology in magnet, foam and adhesive creating the perfect match for our innovative polycarbonate. 
Glazing solutions
Solar Heat Gain
•  Keep you warm in winter, slightly coolers in summer. The solar radiation reaching the sheet is reflected, absorbed and transmitted, as shown in Figure across. The greatest proportion is transmitted and the total solar transmission (ST) is the sum of the direct transmission (DT) and the inwardly released part of the absorbed energy (A).

•  An outstanding feature of Glaze & Save InvisiTherm™ solid sheet is the retention of mechanical properties over a wide range of temperatures. It is characterised by its excellent mechanical behaviour, maintaining high strength and stiffness when exposed to elevated temperatures over a long period of time. For example, it retains 85% of its room temperature flexural modulus at 82°C.
Thermal Insulation
Energy Loss Calculation
•  The need to reduce energy consumption, and therefore energy costs, is one of the highest priorities in any business or home today.

•  Substantial savings in excess of 22.5% are possible when installing Glaze & Save InvisiTherm™ solid sheet instead of mono-layer glass. When calculating according to the guidelines laid out in DIN Standard 4701, an average annual saving of between 0.9–1.3 litres of oil or 1.0–1.5 m3 of gas per m2 of glazing area will be obtained by decreasing the K-value by 0.1 W/m2K.

Single Glazing 

•  When using Glaze & Save InvisiTherm™ solid sheet, considerable energy cost savings can be achieved by preventing excessive heat loss in winter and heat entry in summer.

•  Heat loss is normally recorded as a K- value, which is the amount of energy transmitted through a material per square meter of glazing area and per degree of temperature difference.
•  Single glazing K-values W/m²K - Glaze & Save InvisiTherm™ 5.33 and Glass 5.82
Glaze and save solutions for sash and case windows
Light Transmission 

•  Glaze & Save InvisiTherm™ ensures long-term optical quality under intensive UV exposure, and maintains the superior toughness of the polycarbonate material in comparison with other thermoplastic glazing. Achieving a 87% light transmission.
bespoke shaped almost invisible secondary glaze and save system
Acoustic Insulation 

•  Installing Glaze & Save InvisiTherm™ solid sheet into single or double glazing systems, meets the acoustic requirements of today’s glazing, giving outstanding noise reduction. 

•  We can reduce the noise by an average of 48%󠄨², often achieving much more for single glazing. 

easily removed glaze and save system for cleaning and maintenance
Light Weight
•  Glaze & Save InvisiTherm™ polycarbonate sheet products are ideal replacements for more traditional glazing materials.

•  It is safe, lightweight at 4.8kg per m2 (half the weight of glass of same thickness) and easy to handle, shatterproof and virtually unbreakable. 
Glazing solutions
Fire Performance

•  Glaze & Save InvisiTherm™ solid sheet has good fire behaviour characteristics, and receives high ratings in several major European fire performance tests.  As a thermoplastic, it will melt under the intense heat of a fire, however, it will make almost no contribution to the growth of a fire through flame spread. 

• UK - performance of plastics is tested according to IY BS 476 part 7, giving this excellent high rating.
Glazing solutions
Blocks Ultraviolet

•  Glaze & Save’s InivisTherm™ block Ultraviolet light, eliminating fading on all your internal items. Your plants however will continue to flourish. 
Glazing solutions
Thermal Expansion Allowance

•  Since Glaze & Save InvisiTherm™ sheet has a larger coefficient of linear thermal expansion than that of the glazing profiles commonly used, we take care to allow free expansion of the sheet to avoid bowing and thermal stress. 
  • We make allowance for thermal expansion both for the length and the width of the G&SIT sheet.
U-value from 5.5/5.2 to 1.8/1.6    |   Fire proof Class YB54 76 Part 7    |   Blocks Ultraviolet light, eliminating fading
Glaze & Save has visibly reduced the amount of condensation that we used to face every winter. We have turned our night storage heaters down by two points [approximately 25% in winter] as our rooms were just too hot. We no longer hear the street noise at the annoying levels that we used to and last but by no means least, we sometimes even forget it is there.” 
Chris Steel, Abernethy, Perthshire, Scotland
Share by: