Secondary Double Glazing


Secondary Double Glazing Installers Teford Shrewsbury and Shropshire

 If you would like to see a c thru shropshire secondary double glazing installation please visit Cromwells wine bar in Shrewsbury town centre were we have fit sliding secondary in the bar also virtical Balanced Sliders to all bedrooms


Secondary Double Glazing Telford Shrewsbury Shropshire

Secondary Double Glazing Telford Shrewsbury Shropshire

C Thru Shropshire are the leading installers of Secondary Double Glazing Telford Shrewsbury Shropshire

The term refers to a second single glazed glass ‘window’ being fitted inside the room up to the main (prime) window. These days secondary glazing is used mainly to achieve sound insulation although originally secondary glazing was fitted up to original prime single glazed windows to insulate for heat savings.

For secondary glazing to be at it’s most effective the gap between it and the prime window needs to be somewhere in the order of 50mm-100mm or so. It is very important that the prime window is a draught proof as possible or the effectiveness of having secondary glazing will be reduced.

To further cut down noise fitting acoustic tiles around the perimeter of the reveal, that is around the top bottom and sides between the prime and secondary. These are easily and cheaply obtained from suspended ceiling firms, and if you are lucky you may be able to pick up some damaged tiles cheap that you can cut to size. Leave a small say 5mm gap between the tiles and the window frames.

Good quality secondary glazing does not come cheap, after all it is almost like having a new window. I prefer Aluminium secondary frames because for really effective noise reduction it is desirable to have as much rigidity in the frame as possible. Aluminium frames are available in at least silver, dark brown and white, and as far as I am aware, in several colours.

More on noise reduction:

If you are not interested in fitting secondary glazing but want to reduce noise more than the average double glazing window normal will, then the best way is to have the double glazed sealed unit make up changed from a  4mm – the air gap – 4mm set up, to a 4mm – the air gap- 6mm. Notice I do not mention the air gap thickness, this is because it is of little importance when it comes to noise reduction as a gap as mentioned above is really needed and the small differences in available gaps in double glazed sealed units is almost insignificant.

If you have old single glazed windows and wonder just how well normal new sealed unit double glazed windows will work, then you are probably in for quite a surprise. If you have only ever had single glazing and can’t understand what all the fuss is about with ‘double glazing’ and why it is a must have, I can tell you now that the likelihood is that the noise and heat reduction properties gained will probably far exceed any modest expectations and preconceived ideas you may have.

A lot of secondary glazing is fitted when properties are suffering excessive noise pollution due to their being close to aero planes taking off and landing and also to properties who suffer when a new road goes through.

Typically there are two ways to install the secondary frame, either fixing to the existing framework (face fix), and remember to leave sufficient gap for the handles, or reveal fix where the fixings will go into the wall. The latter method will more likely provide for the wider gaps.

The nuisance with secondary is that because the air space is not hermetically sealed the panes need to be removed periodically for cleaning. Also of course there is ventilation, secondary glazing is no good when you have it slid open and your main window open for some air.


Sound insulation

Sound is produced by vibrations. It is a physical phenomenon that stimulates our hearing senses. In humans, hearing takes place whenever vibrations of frequencies from 15 hertz to about 20,000 hertz reach the inner ear.

Today people are more aware of their environment, the need to increase comfort, safety and other workplace and residential characteristics. The need to restrict sound arriving from the external environment means that glass should be able to shield and insulate while satisfying more sophisticated design standards. The so-called Mass Law is the fundamental principle behind the acoustic insulation properties of glass and windows. The Mass Law demonstrates that, with each doubling of glass thickness, the corresponding acoustic insulation is increased by 4 decibels. As this Law does not take into consideration several other phenomena, such as resonances that affect glass at certain frequencies, it cannot be utilized for precise calculations. There are several factors that influence the passage of sound through glass.

Glass Types:
Glass type is the major factor influencing the passage of sound. The most common types of glass used are laminated and insulating glass (Double glazed). Laminated glass incorporates a special acoustic PVB interlayer, which absorbs some of the incident sound energy, reducing the its passage. This acoustic PVB interlayer can be also utilized to reduce the noise level experienced in cars. Better sound insulation can also be achieved with double-glazed glass. Vacuum-sealed inner spaces, special selection of glass types, and some gases affect sound insulation and provide acoustic stability. All other types of glass such as toughened, coated, wired or patterned glass behave acoustically in the same way as with comparable standard float glass.

Effect of Area:
The larger the glazing area, the greater the amount of acoustic energy able to pass through it.

Effect of Distance:
The more distant the noise source, the greater the decrease in noise level.

Effect of Height:
With a taller building the street noise level is expected to decrease.

Aggregate Review : All Reviews 5 out of 5 , 36 votes , 36 reviews

Work completed and to a high standard

French Doors Stirchley Telford Shropshire

Workmen very good
Double Glazed window Donnington Telford Shropshire.

I am delighted with the French Window and the excellent way the work was carried out, Thank you for sending such skilled and thoughtful fitters. (Rick and Warren)

Shrewsbury Shropshire French Doors in PVCu with Astrigal Georgian bar

Very good clean and tidy work,acted like gentlemen.Well impressed.
Double Glazing Telford Shropshire

Brilliant thank you, Excellent fitters and brilliant service from your rep.

Rosewood Double glazed windows and doors The Rock Telford Shropshire

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We are very pleased with the guardian roof you fitted for us in February, the conservatory can be used all year round Thank you

Guardian roof Muxton Telford Shropshire

Proficient, clean and tidy

Replacement windows Sutton Hill Telford Shropshire

Just a quick E Mail to say thank you for all the hard work and effort you and your team put into my Lean to/conservatory.
I greatly appreciated your help and advise regarding style and design-invaluable.
It was such a tight schedule to have ready for my daughters wedding but you did it and everybody has said what a great addition to the house. I cant praise your work team enough-all of them were so hardworking and efficient and cheerful and helpful. I cant remember all their names but Jason the electrician, Dave the plasterer/Plumber, Ian the builder and those whose names I cant recall-a great team of people.
I hope you can use this as a testimonial because I would happily recommend C-Thru to friends and family and will do so
With all best wishes
Mrs McG

Excellent workers nothing too much trouble, very good relationship with customers created.
Composite Door and replacement windows Wellington Telford Shropshire
Mr Mrs J

Excellent Work Thank You
Double Glazing Muxton Telford Shropshire
Mr Mrs Hardy

Double Glazing Leegomery Telford Shropshire
Good Job,Hard working guys
Mr Nielson

Many thanks for sending our 12 year guarantee for the new door which you recently fitted. We would like to take this opportunity to thank all concerned for their helpfulness, politeness and the professional service we received from the time of ordering the door to the fitting.

Double glazed entrance door Wem Shrewsbury Shropshire

Excellent service from start to finish (initial contact to completion) the installers are a great asset to the company. Excellent service

Replacement Cladding Bridgnorth Shropshire

Would Recommend to a friend

Glass Roof Conservatory Pontesbury
Shrewsbury Shropshire

Very Good

Replacement Window Telford Shropshire

Great Guys Great Job.
Double glazing Wellington Telford Shropshire
Mr Mrs Y

Thank You
White Lean Too Conservatory Wrockwardine Wood Telford Shropshire
Mr Mrs E

Pleasant helpful fitters, very pleased

Shifnal Telford Shropshire glass roof Pvcu conservatory

we would have no hesitation in recommending C Thru

Double Gazing Telford Shropshire

To supply and fit 3 Double Glazed windows
Very Careful and very polite pleasure having them here to do the work
Mrs Dodd

Excellent company from start to finish, first class goods and fitting, Fitters were excellent, polite, obliging and hard working.

Conservatory Shrewsbury Shropshire

Excellent Job
Windows Telford Shrewsbury Shropshire

Wow, what a fantastic conservatory installation. Everything went so smoothly from the initial design stage through to completion. Every one involved was extremely attentive to our needs. It was a real pleasure to deal with a company who focused on a solution rather than hard selling. I would recommend C-Thru every time.

Edwardian Glass roof Conservatory Newport Telford Shropshire

A Lovely job done, more than satisfied, Excellent Windows

Trench Telford Shropshire Pvcu Georgian Windows

Dave and Mark are first class fitters a credit to your company, they are courteous, polite and hard working(as long as you keep up ample supply of tea and coffee!) In general my wife and I were very impressed at the profesionalism of all your staff and would certainly come back again and recommend you to others. Many Thanks

Telford Shropshire A rated PVCu Double Glazed windows

This is the second time I have used C Thru service and product second to none
Windows Telford Shrewsbury Shropshire

Aluminium bifold doors Wellington Shropshire
The guys were excellent in all of the above cant praise them highly enough.
Mr Mrs Campbell

Replacement Windows with square Lead Chartwell green front door
Very nice and polite
Mr Mrs E

Very polite and good workers
Pvcu Door and side panel with window Telford Shropshire

Would recommend you in the future.

Wellington Telford Shropshire Composite Door and Double Glazed windows

Excellent job done
Composite door Telford Shrewsbury Shropshire

Great service really friendly tradesmen, great quality definitely recommend
French Doors Telford Shropshire

Would recommend you to a friend

Warm roof Conservatory Albrighton West Midlands

Pleased with all workers from start to finish.
Conservatory Dawely Telford Shropshire

We are so pleased with the products and the excellent work carried out by the fitters. A job done so well. Thanks a lot.

Randley Telford Shropshire Pvcu Bay Window and Composite Front Door

Having being in the same industry I was very impressed with all standards taken out by C Thru

Conservatory Shifnal Telford Shropshire