Heat Insulation - Standard Secondary Glazing greatly increases the Thermal Rating of the Window - Low "E" Glass can be used to equal or better the Thermal Performance achieved by Replacement Sealed Unit Double Glazing - Saves Energy - Reduces Heating Bills - can meet the Requirements of Building Regulations Document "L" for the Thermal Standard of New & Replacement Windows - Improved Energy Rating for the new Energy Performance Certificate for the Home Buyers Pack.

Sound Insulation - Standard Secondary Glazing achieves a significant reduction in Noise entering from Outside - Specialist Glasses, such as Stadip ® Silence Laminated Acoustic Glass, are especially effective against Road, Aircraft, Rail & in fact any type of Noise.

Security - Standard Secondary Glazing adds considerably to Security - it can only be Opened from Inside - the addition of Toughened or Laminated Glass & additional Locks will Further Increase Window & Door Security.

Dust & Rattles - Because the Internal Secondary Glazing is Fully Sealed there is very little Air Movement within the Cavity, thereby virtually eliminating the ingress of Dust & Cutting Out any Rattling of the Primary Window.

Protect Carpets & Soft Furnishings - Where Secondary Glazing with Laminated Glass is Specified it Protects Carpets & Soft Furnishings by Filtering Out the Colour Fading effects of UV Light.

Character - Secondary Glazing can Provide all of the Heat & Noise Insulation that Modern Living Demands whilst Protecting the Character of Your Home by Retaining the Original Timber or Metal Windows.

Historic Buildings, Conservation Areas & Listed Buildings - Other than in very exceptional circumstances Secondary Glazing is Accepted & indeed Welcomed by Planning Officers as a Much Better Alternative to Replacing Windows & Doors in Conservation Areas & Listed Buildings.

Sealing the existing Windows & Doors will not Significantly or Noticeably Improve either Thermal or Noise Insulation.

Your existing Windows & Doors have been doing their job Satisfactorily for Many Years, in some cases for as Long As 100 Years or More - they were Not Designed to be Fitted with Draught Excluders, Brush Seals or in fact any type of Window Seal - doing so is likely to Stress & Weaken a perfectly good Window or Door & Shorten its' Life Considerably.

Similarly, fitting Sealed Units to existing Casements & Fanlights will Critically Reduce the depth of the Original Frames & severely Weaken the Joints - a Sealed Glass Unit will typically be between 2 & 3 Times the Weight of the original Single Glass and this will Critically Strain the Joints, Hinges, Handles & Locks of old Casement Windows.

For Traditional Sash Windows the problems are more acute, the actual Sashes are far too thin for a Modern Specification Sealed Unit so generally a unit with a 6mm Cavity will be fitted, which will not add much to the Insulation - additionally Staff & Parting Beads will need to be Removed & Refitted or Replaced to Re-cord the Sashes and the Boxes will need to be Opened to Hang Heavier Weights - this is all Costly, Messy Work, for Little or No Benefit & the Window will Require Complete Redecoration upon Completion.

The very Minimal Air Movement within the Cavity between the Secondary Glazing and the Primary Window or Door Prevents Condensation from forming in the gap between them - this protects the Primary Window from Condensation Forming, Condensation laying on Glazing Bars and Heavy Condensation running on the Vertical Surfaces & gathering on the Joints with Horizontal Surfaces, which if left unattended will probably cause mould & rot.

This is particularly important if the Primary Window or Door contains any Traditional Stained Glass - if this is the case then consideration should be given to Fitting a Trickle Vent to the Secondary Glazing in order to Further Ventilate the Cavity - Condensation can be Very Damaging to Both the Stained or Painted Glass & also to the Lead, Copper or Zinc Foil Cames & Securing Wires and also to the Cement (Sealing Compound) used to Glaze the Coloured Glass into the Metal Cames & Surrounding Frame.