Friday, 21 June 2013


Double-glazing for heritage, period & traditional windows

What is an historic or traditional building? English Heritage gives the following definitions: 

Solid wall construction
Bay windows 
Sash windows 
Single glazing 
Built without a damp-proof course
Probably built before 1919

In other words, the earlier traditional homes that form so much of our heritage - many of which are now Listed Buildings &/or in Conservation Areas - with original period single glazing of all types, including: 

Georgian casement & sash windows
Victorian casement & sash windows 
Edwardian windows & doors
Cristal-type steel windows & doors

The installation of discreet secondary double glazing for Listed Buildings, Conservation Areas & all types of heritage & historic windows is considered the best, and in fact usually the only, acceptable treatment: for: 

Creating comfortable living conditions
Reducing energy usage 
Cutting CO2 emissions
Conserving period properties

Apart from the strict regulatory controls on upgrading & improving Conservation Area & Listed Building windows, practical common sense also makes secondary double-glazing the product of choice.

Why Use Secondary Glazing in Period Properties?
During the last few decades of the 20th century, modern replacement windows spoiled the appearance of thousands of old Georgian, Victorian, between & post war houses, flats and apartment blocks.

Additionally, poorly designed replacement windows have actually damaged many older properties, which were not designed to be completely sealed up, by: 

Reducing ventilation
Trapping humidity
Creating condensation traps

To add insult to injury, many fine plaster & timber moulding details around the window reveals were needlessly destroyed.

All buildings need regular changes of the internal air to avoid: 

Damp & mold infestation 
Condensation on windows & other surfaces

This is particularly relevant for our Georgian & Victorian housing stock as these older properties need more frequent air changes than modern ones.

Modern double glazed windows do not enable an old property to “breathe” sufficiently in order to avoid problems and continue in a good, sound condition.

As a rule of thumb, a traditional building needs to be ventilated at a rate of:

0.8 to 1.0 complete air changes per hour
Which is twice that for a modern building

Since natural ventilation rates in many older buildings actually exceed this value, secondary glazing is normally very beneficial in reducing the rate & improving the thermal insulation.

Why Secondary Windows - Why Not Replace Them?
The reasons for using a secondary window rather than a complete new window in traditional properties can be summarized as follows: 

Regulatory control – generally specified by Planning & Conservation Officers 
Aesthetics – secondary glazing does not spoil the appearance of an older property
Protection of the fabric of the building
Protection of the value of the property
Costs of secondary glazing will be considerably less than replacements
Environmental costs of secondary glazing are far lower than replacements, in terms of the manufacturing energy usage and the disposal of the original windows
Most old windows can actually be repaired when necessary, frequently they have been needlessly replaced
Good quality secondary double glazing will be virtually invisible externally and extremely discrete internally
Conservation - to survive both structurally and financially, old buildings need to remain in use but with improved thermal and noise insulation and better security
The value for money will be greatly increased by installing secondary glazing due to the reduced costs of upgrading
Well maintained and insulated period properties are increasingly sought after
Reduced energy costs will quickly return the investment

Granada Secondary Glazing for Listed, Historic & Conservation Properties
In addition to our standard range of discreet secondary double-glazing, we also have a complete suite of secondary windows especially designed for period buildings:

The Granada Heritage Range of Secondary Glazing for Conservation
We have designed our Heritage Range specifically for older, traditional properties - it is unobtrusive but very effective, providing: 

Exceptional heat insulation 
Maximum noise reduction 
Concealed mufti-point locking
Clean, minimal site lines

Fixing methods are also concealed and a sympathetic range of finishing trims and mouldings assists in blending the secondary glazing into traditional surroundings.

Frames can be manufactured out of square, arched, radiuses or curved to achieve the best possible end result.

The full RAL colour range is available for colour matching as well as a wood grain effect - & decorative paint finishes can also be applied, so that each secondary window can be matched to either the existing or proposed decor.

Our secondary windows are installed in all types of period buildings for: 

Heat insulation - can comply with Document “L” requirements 
Sound Insulation - the most effective product for eliminating outside noise
The control of condensation
Improved security

Granada Secondary Glazing Installations
Our secondary glazing has been installed in houses, apartments and flats across the country - everything from country cottages, manor houses, barn conversions, mansion blocks, Art Nouveau buildings and thousands of other charming period properties.

Secondary Glazing Services for Listed Buildings (Grade l & ll) and Conservation Areas
We have worked in Listed Buildings and Conservation Areas for over 20 years and we can therefore give an expert service from initial contact and advice - through to the finished job - all supported by our unique knowledge base, depth of experience and most of all - by our expert personnel: 

Please call us for advice on any aspect of secondary double glazing for traditional properties 
We can provide specifications for your planning application
Request a site visit either for an initial consultation & advice or for a detailed specification & quotation 
Bespoke secondary glazing windows developed for larger individual projects
Complete after sales service – including comprehensive guarantees 
Everything that you need to know about listed buildings & conservation area regulations, including applying for Planning Permission or Consent, can be found here - England & Wales - Peak District - Scotland - NI - Eire - Jersey - Guernsey

1 comment:

  1. Great Information about heritage glazing buildings first time I read this article. Really nice work.
    Secondary Glazing | Secondary Glazing London


Blogger Template by Clairvo