Black Knight Secondary Glazing
Black Knight Secondary Glazing

Secondary Glazing

What customers say about our secondary glazing

These are just a few recent secondary glazing reviews that our customers have given us after we have carried out work for them. 

 I was really impressed with the finished job.


Your staff arrived on time, completed the job quickly & efficiently, tidying up afterwards so you would not know they had even been there.


All this plus a cheery happy approach to their job. (Something that is so often missing these days)


SC Leeds - Dec 2019

Windows all done. Very happy with the results and the tenants even happier.


Very quiet in the house and they look great.


I will have no hesitation in recommending your firm to anyone. 


IH County Durham - Dec 2019

in the words of my son .....”its AMAZING!”


FG London - Dec 2019

Many thanks for completing the secondary glazing to my front bedroom.


The difference in sound reduction is better then I expected & the room is now warmer as well.


SC Leeds - Nov 2019

Just wanted to let you know how pleased we are with the double glazed units.


The black ones look so much better against the black beams & the whole room has been vastly improved.


Adam & Joe did a fantastic job, particularly bearing in mind fitting the units inside irregular beams can’t have been easy. 


JE Dunmow - Nov 2019

Thanks for a brilliant job, and a great team, we're very impressed.


SA Nottingham - Nov 2019

Thank you for a very efficient, professional and personal service. 


We would not hesitate to recommend your company to anyone we know who is looking at secondary glazing.


CC Brighton - Nov 2019

A pleasure to deal with a very friendly and knowledgeable man. 


Very refreshing to meet somebody who really understands the product he is selling and able to offer genuine advice.


IH County Durham - Nov 2019

I would like to say that we are extremly happy about the final result, excellent work! We will definitely order again in the future for the remaining windows, probably around January or February next year.
FB Leeds - Oct 2019
Thank you to your and your team - very happy with the service.
I may well be wanting some more secondary glazing for my living room at some point, and you'll be the first company I call if I do!
JE London - Oct 2019

The work done by your two employees today has been 100% quality from their arrival to finish.


I have never experienced such clean workmanship,  one would never had known I had any work done. The windows have been fitted to a very high standard and


I am more than pleased with them.


Extremely high standard from the beginning to the end.


GW Derby - Sep 2019

I am very pleased.


All your colleagues have been very helpful. And it has all been arranged and executed so promptly.  What a contrast to other secondary glazing suppliers I have come across! 


ME London - Aug 2019

Your guys have done a fabulous job. Please give them special pats on their backs once they are back at base.


They suggested that we don’t play with the windows until the morning, just to give things time to settle. We’re ok with that. In the meantime, we come into the room just to look at the installation. Amazing!


Sincere thanks to you for advising us on what to do. Perfect.


MC Liverpool - Aug 2019

May I say that since day one, from initial contact, to meeting your surveyor to dealing with yourself over operational timings, and finally to the actual fitting, every person I have spoken to or had to deal with, have been very polite & helpful.  It has been a pleasure dealing with your company. 


LM Hull - Jul 2019

I can't speak highly enough of this company. Fabulous noise reduction (including a bay window) on a busy road. Professional, knowledgeable service. Nothing too much trouble. 100% recommend. Thank you, so pleased.
CJ Telford - Jul 2019
Thanks for the quality products on a competitive price.
The service was excellent from initial enquiry to installation.
you helped us to take away one of the issue we had for long time by suggesting the right window.
LJ Orpington - Jul 2019

I am extremely happy with the window re the effectiveness in cutting down traffic noise


GW Doncaster - Jul 2019

Thanks very much for the good work being done, the products is making a huge difference to the property, and your teams were quick and efficient. Pleasure to work with you.
FS London - Jul 2019

Never said thanks for the lads on Friday and the great job you did been away for a couple of days and I was in holiday mode would definitely recommend you and your company again and hopefully have you some more work in the near future thanks again

JM Liverpool - Jul 2019

Very positive feedback from the Almshouse residents, both for the product and for the professional job done by your fitters, who were excellent.


Thanks for your service.


JC Heckington - Jul 2019

Your team did a good job and the noise reduction is significant, we are very pleased with the result.


JC Billericay - Jun 2019

Just a quick thank you for the excellent glazing and fitting. It has made a big difference to the amount of sound escaping from the house.


JB Hednesford - June 2019

Everything installed. Tim did a great job and very quickly!


Now I am enjoying a transformed situation - the second time you guys have done this for me!


PA London - May 2019

Thank you so much for doing the windows, they are absolutely brilliant.


I have moved in and have hardly heard a thing through the windows!


BH Derby - May 2019

We are very pleased with the installation and quality of materials. the two chaps carrying out the work were exemplary. 


MG Northampton - Apr 2019

Just want to say thank you very much for my windows I absolutely love them, very quick service and very good price, it has been heaven with no noisy traffic any more.

Holiday makers hopefully will love them also.
JS Newcastle - Feb 2019
Just a short note to say thanks for the excellent service. Great communication from start to finish. Both the surveyor and the fitter were friendly and polite. The finished job looks great, there was no mess to clear up. 
SD Newcastle - Feb 2019 

I just wanted to let you know that the secondary glazing has made a massive difference at our property at E*** Road, the tenants are thrilled with the difference in noise levels.


JY Sheffield - Jan 2019

The guys were great nice and clean and tidy and did a great job looks realy good already feels warmer.

Thanks for your help and professionalism.

AD Coventry - Jan 2019

Just writing a short note to thank you and your company for the excellent service given to us in installing the phase one of our glazing at short  notice before Christmas.


The very competitive quote , swift and clean installation and competent site staff was a rare pleasure. The installers arrived on time, were cheerful and left no mess. The difference is amazing!


Please pass my thanks to all concerned.


MH Coventry - Jan 2019

It is excellent and such a massive impact!!!


The service was also impeccable and the fitters very efficient and discrete. Will def recommend your company!


SL London - Dec 2018

We would both like to thank everyone involved with the purchase and subsequent installation of our secondary glazing. We are both extremely happy with the product and its results (which exceeded both our hopes!).


One complaint, however, is that we both keep oversleeping!!!! Seriously, what a great result ?.


SS Chorley - Nov 2018

I moved into a cottage with old style windows the cold from the metal frames and the draft from the frames was costing me a fortune in heating bills plus made for a miserable winter last years.


Today I have just had secondary glazing fitted and I'm thrilled to bits with the result. Graeme was such a pleasure to deal with and obviously knew his stuff when he visited. Peter who fitted the units was polite, cleaned up after he had finished and was respectful of my home.


I would highly recommend Black Knight to anyone wanting quality and a competent, reliable service. 


TT Banbury - Nov 2018

Excellent team you have and nice to see your son following in your footsteps. The windows are great and perfect sound proofing. 


EC London - Nov 2018

Firstly, may I thank the team - Graeme, Peter and Joe.
They all did an excellent job and on this, the first day, we are very happy with the quality of workmanship and the service provided.
Anyone needing secondary double glazing will get sent in your direction.
KT Oakham - Nov 2018

I would like to thank yourself, Graeme and the fitters. We are extremely impressed with the whole process from start to finish.

The lads left no mess and were very professional and a real credit to your company.
Instantly I can tell a difference in the place and are very happy we went with you.
CT Retford - Nov 2018
Sincere thanks to Peter & Tim for their work on Monday, particularly for their efforts to save the blinds and adapt them to fit over the installed glazing.
The noise has significantly been reduced and we think that the current aesthetic is the most desirable option. 
We shall highly recommend you to others, the communication amd workmanship has been nothing less than impressive. Many thanks indeed.
AC London - Oct 2018

Thank you for your help with this it’s been a pleasure to deal with you and your company from the very beginning. The windows are amazing we couldn’t be happier.


DB Wolverton - Oct 2018

Thank you very much for arranging for the installation to be carried out so quickly. The chaps were very careful and efficient and we are very pleased with the unobtrusive design. It may be our imagination, but an hour after completion the room feels warmer already.


We have two neighbours who may contact you once they’ve been to see our panels.


MH London - Oct 2018

The job is excellent really well fitted and we noticed the difference in the acoustics straight away, and based on how well its fitted we should notice the performance in thermal as well. The looks are great really does look like its one unit with the existing windows. Very very pleased


Adam and Tim were brilliant very helpful very clean and proud of their work. Adam helped me out with drilling a hole to relocate the telephone line. Top job by them.


BC Bebington - Oct 2018

I just wanted to take this opportunity to express my heart felt thanks for an outstanding service, as well as for such a superb product.  Combined with such professional installation.
Rarely does the purchase of a single product have such an extra ordinary effect on the quality of daily life & well being to such a degree.  However, in this instance the secondary glazing has provided near perfect 100% sound proofing. It has utterly transformed my office bedroom into a sanctuary of calm, of deep peace & quiet. The difference is incredible & the effects beyond my expectations & hopes. 
Since installation of the secondary glazing I now no-longer hear any of the following since installation.
• No traffic noise from Kirkstall road.
• No Ambulances or Police sirens (which were especially intrusive)
• No House alarms (which can ring for hours)
• No Low flying Aircraft or jets
• No car alarms
• No music from rental tenants in the street
• No loud talking & conversations in the street at night
• No disturbance from the neighbour directly over the street at No.28 (late night parties).
Note: Have now stopped having to use ear plugs just to get a normal nights sleep.
My room has become a space in which its now a great pleasure to spend time in.   I have needed this deep tranquillity ever since being bereaved & having moved back to Leeds. About three years ago. The stress & anxiety I used to suffer from in the past few years, due to noise nuisance has literally gone.  Knowing that the secondary glazing is a permanent fix is also very re-assuring.  Having broken sleep is awful but these concerns are all ancient history now.
My only regret is that I didn't have secondary glazing fitted two or three years before when noise was causing me even more distress & annoyance. 


IR Leeds - Sep 2018

Matt visited Carlton yesterday to meet the client. They are very impressed with all of your works they love the doors especially.


Thank you for your efforts on this project Graeme it’s very much appreciated, and we understand it wasn’t easy at all.


SJ London - Sep 2018

The product is excellent and the installation was carried out in the most professional manner. Unfortunately, we are not good on names but please thank the installers for their quality installation with absolutely no mess- some of the single glass replacements were to say the least challenging.


AC Telford - Sep 2018

I would like to thank you and your company for all your help and service . We are very pleased with the quality of the windows and high standards of workmanship . 


TI Spilsby - Jun 2018

Thanks again to you, Graeme and the team for providing such a helpful and professional service - I will certainly be recommending you to anyone I know who is interested in secondary glazing.
TE Oxford - May 2018

If you are reading this review with the intention of deciding whether or not to contact Black Knight Secondary Glazing - hesitate no longer. You too will be impressed by the professionalism of the customer service not to mention the quality of the product both in terms of survey, fitting and result. 


We are nothing short of delighted that we were recommended to Black Knight. Our issue was traffic noise in the front bedroom which caused severe sleep disruption. The window is a Victorian sash wooden window which we didn't want replacing by plastic.We can honestly say that our noise problem no longer exists and despite Black Knight not over-promising, this is the true result and we are thrilled.


Thank you to all the team. You have changed our lives.


JR Adlington - Apr 2018

The guys have finished the job and I'm very pleased with the work. The product is amazing and it meets my expectations. I can sleep well in the night now. Please send me the quotation of other two windows. I'm happy to place the order again. 


YS Liverpool  - Apr 2018

Thank you for the great service your company provided. We are so pleased with the secondary glazing that was installed so professionally by your fitters. 
Our initial worry was that the windows would be obtrusive and wouldn’t blend in well with our house. We needn’t have worried, they are really good.
JC Leicester - Apr 2018

Just had my secondary glazing installed in my bedroom and delighted with the results. Black Knight have been a great company to deal with and everyone has been very friendly and helpful. The work was carried out quickly and to a high standard. The result is very neat and flush and almost invisible. I had initially contacted the big glazing companies ans was told by ******* they would not work above second floor and ******** said no company would privide secondary glazing for French Doors. So glad I found Black Knight.


JA Glasgow - Mar 2018

just a quick if belated word of thanks to you and your team for a great product, very professionally installed and thanks too for helping Matt & Cora out in their hour of need.


If I can make one request, could you send me another pair of keys as you will remember one new window is at one end of the apartment and the other three at the other end and as you might imagine, the keys are always at the wrong end.


Many thanks and as they work so well we are now considering doing the study and second bedroom!


RC London - Dec 2017


I am really pleased with the windows and the service that I  received from Black Knight. We had a challenging fitting next to a very noisy road in an old house with sash windows, so it wasn’t straightforward. The windows have made such a difference and your fitters went above and beyond, they couldn’t have been more helpful. We’re saving up to get the rest of the windows done now! Thank you


CP Hebden Bridge - Dec 2017


The windows are amazing! Like absolutely amazing. The sound quality is just fantastic.


Thank you so much for helping me through the whole thing.


AC London - Oct 2017

Tim and Adam did a marvellous job and I'm delighted with the windows!
AR London - Oct 2017

We are impressed by how nice the result is. It looks aesthetically perfect and we can open each window without problem.  Thank you so much!


ON London - Oct 2017

Many thanks all went well Windows look great. The fitter were nice guys good clean working and very courteous. Excellent service.
CH Ely Aug 2017
... love my new window!!!!!!!!  Thank you
JP Northampton - Jul 2017

Thanks for the professional service. 


There is definitely a noticeable sound reduction in my sons room. Hopefully We will now get a full nights sleep without him coming into our room.


AA Darlington - May 2017

Your guys were excellent: punctual, really friendly and efficient. Very happy with the finished article, so all in all, well pleased!


PC Coventry - Apr 2017

The window looks absolutely wonderful, thank you so much! You really have been a lovely company from start to finish, we will absolutely call you again if/ when we would like other Windows doing.


LS Northampton - Apr 2017

I am very pleased with my windows and with Tim and Adam.They were so careful and courteous and a pleasure to have in the house. My Father came from Nottingham and it was a bonus to hear the Midland accent again.
I am thinking about having the front bedroom windows done if you can fit me in at some time.
CP Nottingham - Apr 2017

Thanks for the great job of the windows they look great and the sound is massively reduced


RL Chester - Mar 2017

Super impressed – already made a huge difference and installers were very quick and professional.


KB Stockport - Mar 2017

They did a great job of the windows. The sound is much better and they look lovely too, thank you!


CB London - Feb 2017

Thank you David the window has really helped the problem !! And the young man who fitted it is a credit to your company very efficient and hard working done a lovely job ! Thank you...

ND Leicester - Jan 2017

I was really happy with the efficiency of the guys that did the fitting - you wouldn't know they'd been here, so clean & tidy!


The windows seem great and I had a solid nights sleep. The traffic noise is just a hum now so that's perfect. I'm pleased with the look too. And they managed to move the blinds to the outside so many thanks for arranging that.


GS Manchester - Jan 2017

Delightfully discreet very pleased!


CC London - Jan 2017

Just a quick note to pass on that the secondary glazing has worked a treat. Our first floor has not been cold in winter for the first time in 20 years!
ND Cambridge - Dec 2016

Your Tim and Joe did a first class job of installing our secondary glazing this morning and we are delighted with the final effect.


TH Letchworth - Dec 2016

Both Adam and Joe have done a brilliant job and they are a credit to your company.


I am delighted with how the windows look.  The workmanship is fantastic and the difference it has made is unbelievable - please pass on my sincere thanks to them both.


I have also passed your details to my neighbours


It's  been a pleasure.


ZC Manchester - Dec 2016

As you know your boys installed out replacement secondary glazing in rear kitchen and they look brilliant!


Without a doubt improvement on what was there before - so very many thanks - it was definitely worth doing 100%

CH London - Oct 2016

Great job thanks.


They fitted an extra piece of batten in order to get the blinds back up without interfering with the new curtain track.


Looks the business, improved warmth and reduced road noise


PC Sheffield - Oct 2016

I am very pleased that we have asked your firm to make and fit the secondary glazing units.


From the one completed window already fitted yesterday may I say how clean, clear and elegant the glazing appears. Furthermore is does what you said it would do - that is, significantly cut down the level of noise.


So thank you very much for your care and attention to our needs. It has been a delight working with you and your professional and helpful team.


SB Birmingham - Oct 2016

Hi Graeme, just a quick thank you for the windows - happy client that is more than happy to be used a a reference or supply feedback for you. The fitters were excellent in doing their job.


MC Bracknell - Sep 2016

Black Knight carried out quite a large project at my house, secondary glazing several large stained glass windows in my house. The experience from start to finish was great, the whole process was smooth and very professional and the results were fantastic. I would highly recommend them and would have them back tomorrow if I had any further work for them.


The company is small and with that comes a very personal service which you simply do not get with the larger companies. Black Knight care about every single aspect of the customer experience, from listening to what the customer wants and discussing how to achieve it, to getting the job completed and ensuring they do a good job. The whole team from the office staff to the Graeme the director who comes and consults with you to the team of fitters, they all work to a very high standard and have an excellent level of professionalism, they take incredible pride in their work. I honestly cannot sing there praises enough. Graeme and the team are super and we have recommended them to others.


The work was done quickly and now we have a much warmer and quieter house thanks to the team. They went to the trouble of replacing some old plain window panes for us as well as resolving an issue with rotten timber frame, taking all the worry and stress away from us as clients.


If you do not use Black Knight for your windows you have seriously made the wrong decision. We personally found the larger, more well known companies to be pushy, very expensive and we just did not get the same level of customer service and consideration. I loved everything I saw on the website and then once we spoke in person with Graeme we knew we wanted to work with them and my word we have not been disappointed at all. So many people comment on how lovely our windows look and how we have managed to keep the character of the original windows even though they are secondary glazed, they are very discreet and do not interrupt the view of the original window.


10 out of 10



KL Birmingham - Sep 2016

Outstanding  windows, service, advice and, price.

I am really pleased with the way Black Knight team has worked in every step of the installation of my secondary glazing units.


RC - London Aug 2016

Everything appeared to go well with the installation of the three units, and the results are very pleasing.  The difference in just the sound insulation alone is most noticeable..
It has been a pleasure to do business with you and you will certainly be well recommended by us.
VH - York June 2016

The windows are great! My ear plugs are gone & it's made a huge difference.


JL Oxford - June 2016

I just wanted to say that the Windows have been completed and we are very pleased with the installation.


The fitters have been excellent in their efficiency and workmanship. I would also like to thank you for your understanding and flexibility during the process.


All issues and delays, none of which were caused by your company, have been dealt with with patience and calm consideration which we appreciate.


I am very pleased that I chose Black Knight and would have no hesitation in recommending them to anyone. You have acted like an advisor throughout and if we decide to have further secondary glazing in the house we will return to you without hesitation.


PO Lichfield - May 2016

The joiners did a wonderful job and the noise levels are so much better.
I so wish we'd done this years ago so that we could have benefitted from this vast improvement but you live and learn.
All in all a brilliant job all round and the colour of the paint finish is spot on.


DH Esher - May 2016

Having had the secondary double glazing in place for just under a year now and with winter finally over I am very pleased to be able at last to send you the promised feedback and to once again thank you for your excellent service.


Firstly the whole process from first contacting your company, to fitting the secondary double glazing panes has been fantastic. Highly professional, efficient and a high standard throughout.

Secondly, although it was not the primary aim of having the secondary glazing fitted nonetheless the outside noise reduction is is very significant. I live in a busy part of the city with its fair share of typical and expected noise. But I must say that once the panes where in place all that noise has almost completely disappeared.

And finally, the main reason I had the secondary glazing installed is that I live in an old Victorian building with very thick walls and original wooden sash windows, who look beautiful but are really not very useful when it comes to keeping the drafts and cold out.

Having the secondary double glazing on all 10 windows has kept the average temperature inside my flat (which has a large open-plan lounge/kitchen with a high vaulted ceiling) by at least 2 degrees higher than last winter, before the secondary glazing installation. And also it doesn't sound like much, nonetheless it meant I didn't have to heat the place up as much as I did last winter and the place stayed draft-free all winter. An all that at a very reasonable price too!


JM Southsea - Apr 2016

We are delighted with the new secondary glazing in our lounge. It has been beautifully made and fitted.


It looks really good, but it is early days for saying what difference it has made to the warmth of the room - we'll have to let you know!


For now, we want to thank you for visiting, explaining, demonstrating and quoting and for the professional job done by your joiner. He also  was punctual, pleasant and efficient. The window was fitted quickly but with great care and my husband was given clear cleaning instructions.


Many thanks to you all for a really lovely job.


TW Bolton - Mar 2016

I am delighted with the windows first class job.


I have done the bank transfer for the full amount you should receive the money by end of business tomorrow.


BG Southampton - Mar 2016

Delighted with the windows which have been beautifully installed.


GT-S London - Mar 2016

Just wanted to say thanks for the excellent glazing your team installed. We are very pleased and will not hesitate to recommend you.

CC Croydon - Feb 2016

Your team were pleasant, affable and hard-working and we are delighted with the result. Nice design, conscientious workmanship -- very good value.


The house is noticeably warmer and at last we can go into the bathroom without screaming!


JB London - Feb 2016

Job has been completed to my entire satisfaction. Fit is better than ******* in the sense that the panels are much easier to remove. Noise reduction is better as well. Thanks for the great service. It is refreshing to deal with a company that still provides such a high level of service at a reasonable cost.


IC Birmingham - Jan 2016

Thanks for your exceptional service from the initial sales call, through to the informative and professional visit from both your representative when measuring the windows and the two gentlemen who came to install the windows.


The windows are fantastic and deliver on all the promises made, with the level of sound reduction achieved being beyond my expectations.


Please thank your team for all their efforts.


PD Bath - Jan 2016

I thoroughly enjoyed fitting the windows, especially working with professional individuals who know their trade. Tim who was most helpful.


A pleasure doing business with you.


AR Redhill - Dec 2015

I have a tricky arched window that several companies refused to take on. However, David at Black Knight quickly replied to my email to explain they could solve the issue. This was followed by a phone call from Graeme who explained different options to me and possible solutions.


I was deeply impressed with both the quick response and their determination to see the job through. Graeme arrived to take measurements the following week, and I trusted him immediately with the task at hand. His colleagues arrived just a few weeks later to fit the window; the job was not easy, but finished to the highest specification.


I am absolutely thrilled with the product - I never thought Secondary Glazing could look so stunning. It does not detract from the Victorian arched windows and the quality of the product is remarkable.


Most importantly, the room is now soundproofed to an extent that I never expected. I would thoroughly recommend Black Knight to anyone seeking secondary glazing.


EC London - Dec 2015

Just a quick email to say thanks. We are so impressed with the quality of the secondary glazing we had the best sleep since moving in last night. It's absolutely brilliant.

The guys have done an outstanding job, they were unable to block up the vents with the acoustic wool in the living room because the blinds were fitted to close but did do the vents in the study. Because it has made such a difference in the study would you be able to let me have some of the wool so I can get the blinds taken down and I'll put the wool in myself because that on its own makes a vast difference and I forgot to ask them to leave me some out.


LC Milton Keynes - Dec 2015

We are very happy, Boys were a pleasure to have in my home. So tidy and now sitting in the lounge with no car noise and no draft, and a large glass of red wine to celebrate. Our next door neighbour has already been in to see what we had done and was very impressed with the finish.

I can only thank you for a job well done.


JC Ilminster - Nov 2015

We have just had two units fitted and I can highly recommend them for looks and efficiency.

The technicians who did the fitting were very professional in their work, and there was not even a speck of dust around when they had finished the installation.   They even removed their boots when they entered the premises.   Something that some workmen forget to do!!

All in all a most satisfactory transaction.


VH York - Oct 2015

Just wanted to say thank you to you and your team.  My bay window looks great.


CB Nottingham – Oct 2015

We have just made the payment to you by BACS We are very pleased with the job. The fitters did an excellent job. Very neat and tidy


GC Lincoln - Oct 2015

Honestly, the job was above expectation. The guys were hard working and explained very clearly how it all worked. The product is first class and looks great. You can hardly notice they are there. I slept wonderfully last night and I think we could not have asked for a better result. The sound reduction is very substantial. I am most impressed by the elegance of the design.

From start to finish, it has been a real pleasure dealing with you and your colleagues. Professional, friendly, accommodating and was clear to me that everyone takes pride in their responsibilities.


AB London - Oct 2015


I am very happy with the whole experience of dealing with your company from when I first made contact to when the expert fitters had finished. I had struggled to find a suitable solution for road noise coming through my large 6 panel bay window in the living room. I have plantation shutters and was told by another company that secondary glazing not an option. However I now have secondary glazing behind my shutters and the you would never know. I decided to go for the Stadip sound reducing glass with lift-in, lift out glazed panels. The fitting team took down and refitted both the shutters and the blinds which was brilliant. In terms of noise reduction from the busy road I am very happy with the products performance. It really does make a difference and the room is a haven of tranquillity and also much warmer. I will now be able to put up guests in the room if needed which would have been impossible before due to the noise. Thank you again.


NP Manchester – Oct 2015

I've been meaning to thank you so much for the wonderful job that you, Tim and Joe have done on the new windows. I'm just so impressed with your team! I've been praising Black Knight to anyone who will listen - great design, work done on time, excellent quality product, all mess cleared up! To say nothing of lovely people. It's been a real pleasure to have you doing work on the house.


Of course you'll be welcome anytime to have a look at  your work!


CP Sheffield - Oct 2015

The product is brilliant! I can hardly hear a thing even when lorries or motor bikes go past. Didn't sleep v well last night. Too quiet! Silence has an ambience & hum all of its own. Or maybe it's my ears! The guys who fitted the product were great & v tidy.


 JT-H London - Oct 2015

Many thanks to this exceptional company delivering outstanding service! I now have an amazing sound proof and great looking window! I have gone for the top range and very happy.Very good value for money and high quality work.


EDR London - July 2015

I have recently gone through the sales procedure and fitting of secondary glazing for my home with two companies.


One a national household name, which was a disaster from start to finish with poor workmanship and late delivery.


By stark contrast I have been delighted with Black Knight. no pushy salesmen, they actually listen to what you want.


A good price, delivered on time and the workmanship is excellent. I cannot recommend they highly enough. 


A brilliant company.


TH Tideswell - July 2015

We just wanted to say how much we have appreciated the service we have received from Black Knight.


There have been a couple of obstacles to overcome with the installation of our windows but every one has been great and gone out of their way to come up with solutions.


From Graeme to Tim and the rest of the crew we can only say thanks for doing such a great job, keeping us informed and delivering the product you promised.


We are so grateful we came across your website.

SC Manchester
- June 2015

Tim has finished with the installation of our new window.


All I can say is wow...What a difference and it looks stylish.


Please can you send us the invoice, so we can arrange payment.


Tim was very friendly and professional. He cleaned up after himself, which we appreciated. He really is a credit to your company.


It was a pleasure doing business with your company.


WM Sheffield - June 2015

I wanted to thank you for the way you have done business with us.  From the first enquiry to the final installation you have been efficient, friendly and courteous.  We are very  satisfied with the product and the noise reduction is very noticeable - which is exactly what we hoped for.


We were particularly impressed with your installer, Tim.  He was very considerate, kept us in the picture with what he was doing, did a first class job as far as we can tell and left the place cleaner than how he found it! 


Please pass on our thanks to him.


DH Sutton Coldfield - May 2015


We are very happy with the secondary glazing and the service provided by Black Knight (professional & friendly all the way from the inquiry to the quick and clean installation). The windows look smart and most importantly they make significant difference. Since we moved to our new home, we were not able to sleep in our master bedroom because the noise coming from a street was too disturbing. Now we are back to our master bedroom and we can sleep comfortably. I have to say Black Knight did a great job and I can recommend them highly!


Thanks for a superb job; we are very happy with the quality and the difference it has made to our home.


Look forward to talking again in the near future when we come to tackle the next lot of windows!


Thank you very much!


TB High Wycombe – May 2015

I've just transferred payment for your invoice online.


Thank you very much indeed for the excellent service we've received. Graeme was a superb point of contact throughout.


As discussed I'd be grateful if you could please provide me with a quote for further secondary glazing for my lounge windows.


Kind regards


AD Penarth - Apr 2015

I have got the secondary window installed in the bedroom for Ramsay House.The company that did it was Black Knight secondary glazing. We decided to go with them after doing a lot of research and going to many window companies.(Some window companies said they cannot do it). I can say Black Knight did a first class job and I can recommend them highly.They are very professional and give you the best service.


They charged me around £1100- 1400 depending on your needs for the secondary window. I am very pleased with the service and they have high expertise in the business.The Director Graeme is familiar with Ramsay House and he went out of his way to help us. He is very knowledgable and accommodating.


AD Harrow - Apr 2015




It's fantastic, David. B***dy brilliant haha!


SC Sheffield - Apr 2015

"From the moment of first contact with Black Knight, I felt I was dealing with a professional, knowledgeable, honest and courteous company and so it proved.

I was kept informed throughout and every effort was made to fit in with my ongoing refurbishments.

I am happy to recommend Black Knight without any reservations. Thank you."


JG London - Mar 2015

I am really pleased with secondary double glazed windows that fitted yesterday to our two sash windows. Tim carried out a lovely job and is a very pleasant man. The sound reduction results have amazed me and I can hardly hear any traffic now. 


BS Ampthill - Feb 2015

What a pleasure it has been to be a client of Black Knight.


The customer service is exceptional, from initial contact, followed by a very detailed quote with all options of costs, timings aimed at my convenience, and skilled installation as well as a clear demonstration of how to operate their easy clean system.


It is a very competitive market and there are possibly other firms which might quote lower. However Black Knight is not only excellent value for money, their integrity and conscientious service will be very difficult to beat.


VM London - Jan 2015


I would like to commend the fitters who did an excellent job and worked very tidily, cleaning everything up before leaving. The secondary glazing itself also looks very professional.

I am pleased to say that the new secondary glazing is making an appreciable difference, even though Graham explained it would be quite challenging to obtain such a result, given that I had already got secondary glazing. The new installation is fully meeting my expectations.

All in all, I would like to commend your company's professionalism and the quality of its product.  I would have no hesitation in using it again, should I need to do so, or in recommending it to anyone else.


RC Wellingborough - Dec 2014



We're really pleased with the windows, they look great and we're already feeling the benefit warmth and comfort-wise. We've not had a single bit of condensation since the installation and the house is generally a lot warmer! It's fantastic and novel for us! I don't think it will be long before we'll be back for the remaining two windows to be done!


MB Yorkshire - Dec 2014



We have now had your new secondary glazing for two weeks and we have to say the outside noise reduction is superb, far better than we were expecting.


We know how challenging it was to fit the windows on a round bay yet you managed it perfectly.


Despite being Leeds Utd supporters (!!) your fitters did a great job, making good all round the new windows and leaving the room clean and tidy.


We would like to thank you for all the time and effort you put into our new windows and we can now look forward to peaceful nights sleep.


R&J P Brighton - Dec 2014 



Thank you for your help at every stage of the process. BK always returned calls promptly and were clear on both product and price. A fantastic company to deal with and a great product.


RJ Essex - Dec 2014


I was in touch with Loredana today and she is really pleased with the window and had
nothing but good things to say about your guys. In her words she has never met 
cleaner, more efficient and hard working men!

Thank you – all your efforts much appreciated and please feel free to send the invoice, 
I will see to it being paid as soon as I receive it.


NR London - Sep 2014


I am absolutely thrilled with the windows! I cannot believe the difference it has made to the noise. You have been a total God-send!
It really has been such a hassle-free and successful experience with yourself and Black Knight. 
Thanks so much again.
EE London - Sep 2014


Thanks to you and team! Fabulous job. Why didn't I have it done years ago!?


My dad loved them! He said they were just leaving but agreed to come back in to talk him through mechanism. He thought they were both lovely guys. Couldn't be happier with job!!! Feels like a proper flat now. No longer feel like I'm sleeping on junction road! Noise was so bad before. Now it's almost silent. Completely perfect! Also the look I was so worried about is completely fine. Really am delighted with end result.


Couldn't be happier! Please thank your team on my behalf! Graeme was a pleasure to work with and your team were super nice to my Dad who wanted them to talk him through mechanism when they were just about to leave!
I paid the amount, in full this morning. Should show up in your account in next couple of hours.
Super job! Can hardly hear the main road now! And I needn't have worried about aesthetics. It looks fantastic-just as Graeme promised! 

CS London - Sep 2014



Thank you so so much for you and your team's skill, attention to detail and professionalism in designing and installing our secondary glazing in the bedroom. We are very happy indeed with the results.


They look amazing and you have managed to make them blend into in our 18th century house. The sound proofing effect is amazing - until we get used to it is is almost "too quiet"!

Seriously, thank you. Please pass my thanks on to the installation team who came yesterday. We are looking forward to getting the lounge done on the 15th.


Also, if you can tell us how much it would cost to have the 3 second floor bedroom windows done that's be great 


KL High Wycombe - Sep 2014



Window is stunning. Very impressed.


RC Manchester - Aug 2014



Many thanks for the work you and your team undertook for us recently.


We're delighted with the quality of the work and are grateful for the recommendations you made around the best choice of products. Your vast experience here was invaluable and really came across. We have 3 front facing rooms on a busy main road, whch can now be used as bedrooms upstairs and a lounge where I can finally hear my television easily, with no road noise! The draughts have disappeared too, and with the installation being in summer, I've noticed how much warmer the rooms are this year. I can't wait to see the improvement on our previously sky high gas bills this winter.


Finally, we're really grateful for your help in making sure we were able to achieve what  we wanted within a sensible budget, without compromising or cutting corners. We would of course be happy to use Black Knight again, and would have no hesitation in recommending you.


Kind regards


J&KW Leicester - Aug 2014



On time, as promised - and superb support from initial contact to final delivery


PW Guildford - Aug 2014



Excellent company to deal with. Friendly staff, great product and they did what they said they would when they said they would. Secondary glazing has made a real difference to the sound coming into the rooms. Would definitely recommend!


ML Brighton - Aug 2014



WOW! And that's without actually testing the noise performance yet. Now I am actually WANTING the noisy gardeners to come with the strimmers, mowers and leaf-blowers. Why I am saying "wow" before even knowing that side of things is because they LOOK and FEEL fantastic. And your fitters (that label doesn't seem grand enough to describe them) were a couple of the nicest guys I have had the pleasure of meeting. Seriously though, what a beautiful job and a painless eXperience.


Fantastic solution to a major noise issue. Exceptional communication with me and my acoustics advisor, no hard sell, and beautiful product, installed quickly by great, highly-skilled guys. Can't recommend enough! 




PA London - Jul 2014