Secondary Glazing

What is Secondary Glazing?

Secondary Glazing is the installation of a second pane of glazing inside an already existing pane. It is a cost effective solution to double glazing as the existing window is preserved and the secondary glazing provides many of the same benefits.


At Windowseal we can provide custom built and fitted secondary glazing to suit any of your needs.

Benefits of Secondary Glazing

Secondary Glazing
Secondary Glazing

Windowseal Secondary Glazing Systems are the best solution to:


  • Getting rid of draughts and cold-zones around existing windows
  • Increasing insulation levels in the building and also retaining expensively generated heat thereby maintaining comfort levels
  • Providing extra security to primary windows (units come with additional finger locking devices)
  • Dramatically reducing noise levels (up to 70%)
  • It costs only a fraction of cost of replacement windows 


Installation normally takes only one day with minimal disruption – there is no mess and windows resume normal duty on same day.

Secondary Glazing

Our Secondary Glazing Technology


We use Add-A-Pane Secondary Glazing to negate draughts (100%) and get rid of cold zones around your existing windows, increase comfort levels, improve security levels, reduce energy bills, dramatically reduce noise levels - up to 70% reduction is noticed in reduction of outside noise transmitted indoors when Add-A-Pane Secondary Glazing is fitted and also add value to your property. 


Add-A-Pane Secondary Glazing is stylishly designed to blend in unobtrusively to most windows, with alternative types of tracks to suit different styles of windows. Efficient double-sealing panels are easily removed for painting and decorating etc.


More images available in our gallery


Secondary Glazing - General Information

Secondary Glazing is an independent internally fitted window, usually fitted on room side of any existing primary window, thereby not having to remove good quality windows, which may be too good to replace. It can also provide up to 70% reduction in noise permeating through the windows as result of road traffic, human traffic, animal and other noise issues. 


It also improves thermal insulation, can reduce the ‘U value’ in single glazed windows from an average of 5-7 ‘U’ value - down to less than 2 (if using ‘Planibel G’ Low-E Glazing). In the process it prevents heat loss (by up to 67%), eliminates draughts and gets rid of those cold-zones around window frames.  


Using ‘Planibel G’ Low-E Glazing is the best option to provide additional comforts and maximum Energy Conservation.    


On Sound Proofing applications - the use of the most modern glazing techniques assist with acoustic values. Using a 6.4mm laminated glazing, maximum sound proofing can be achieved.  


The Secondary Window is discreetly installed by our trained craftsmen to match existing décor and comes in white or brown colours as standard. All other RAL colours can be matched. 


Available in a horizontal sliding / vertical sliding, ‘In-Frame’ hinged, fixed or lift-out panels, matching all requirements and designs. 


Secondary Glazing has been the choice of professionals worldwide for many years and has been fabricated here in Ireland since 1985 by Wind-Do Seal Ltd with total success. 


Wind-Do Seal Ltd has been working closely with the accommodation sector for many years to assist in making bedrooms in many of Irelands leading Hotels, Guest Houses and BnB’s, more comfortable to stay in - by having our Secondary Glazing fitted to their windows.  


Since 1985, Secondary Glazing has been the choice of professionals as a Thermal and Sound Proofing option in the accommodation sector in leading hotels, Guest Houses, Government Buildings, Offices, apartment dwellings in busy thoroughfares as well as for thousands of homeowners nationwide. It is an ideal solution on listed buildings, preservation structures and conservation projects to help maintain existing facades, aesthetic appearance, character and value. 


On Sound Proofing projects, Secondary Glazing frames are made from tough, robust, yet aesthetically appreciative, slim-line powder-coated aluminium and are securely fitted using a packer-frame to resist force and also create an ‘air gap’ of (150mm – 200mm) between the primary window and the Secondary Window. This ‘air gap’ is necessary to create maximum Sound Proofing effect. 


On Energy Saving projects we attempt to fit the glazing onto the outer frames of the primary window as ‘air gaps’ are not necessary.  


Secondary Glazing helps deter would-be intruders, helping to reduce force impact by the use of packer-framing, resins and toughened glazing. Commercial buildings can be prime clients for Secondary Glazing as they can be targets for commercial vandalism or theft of goods.


Secondary Glazing can exceed building regulations, provide ultra-quiet living conditions, provide significant energy and financial savings and enhance living conditions.  


Technical Info for our Secondary Glazing Products

File Download
Specification leaflet for our secondary glazing and sound proofing system
Adobe Acrobat Document 35.5 KB
Technical specifications & drawings of profiles
Secondarys Drawings all Sheets V1.2.pdf
Adobe Acrobat Document 1.5 MB
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T: 087-2693329




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