Core Sash Windows

Public evidence profile

Core Sash Windows

London
4.663 reviews in the current record
Reviews

What customers say about Core Sash Windows

4.6out of 5
63 reviews in the public recordCross-checked across 1 source
Which? Trusted Traders25 reviews · 5.0 avg

Highlights

"We had new bay and sash windows from Core Sash. All the staff we dealt with were professional and polite. They took care to minimise mess and inconvenience and the finishing off work was excellent. We had to pause work due to a leaky roof and this was accommodated without fuss. The finishing off work breathed new life into our rather worn and old plaster work and ledges."

Customer in Greater LondonWhich? Trusted Traders5.0 rating

"We had 6 sash windows and 1 casement installed in Dec 2019. The installation team arrived on time and were respectful both to us and our property. They kept us informed and cleaned up each day to a reasonable standard. The finish on the windows is fantastic: the final hand coating of paint (by Steven) makes all the difference, and not many companies I had quote offered this. I had previously had 2 sash windows installed by another very large company (LSWC, green logo!) and these windows by Core win hands down - both on appearance, smoothness of operation, and the “making good” of surrounding plasterwork etc. A special shoutout to Steven for that. We did have an issue with on one of the 7 windows we had installed - the architrave used was too large compared to the original and as installed was overlapping the rooms cornicing which spoiled the look of the room. There was a bit of back-and-forth with the company on the matter, necessitating some before and after photos to show the original appearance, but afterwards they did agree to return and fit a smaller architrave at their expense. In an ideal world this would have been picked up by them during the survey and adjustments made ahead of time, but credit to Core, they did return and put it right, so no hard feelings from me and they will be my #1 choice for next time given everything else was top-notch. No experience (yet) of having to call on their warranty."

Customer in Greater LondonWhich? Trusted Traders5.0 rating

"We had to replace the top sash of one of our windows. After some research and other good reviews I have seen on Which, I decided to go with Core on this. Their sales team is very helpful, answers all of your questions and pays attention to your needs. The new sash production was on time as promised. The job was scheduled and completed on time as promised. They came in and worked so diligently, when they left, there was not even a single dust in the room. And the window was fitted so nicely and is now operating smoothly. Core has done a great job and if I am ever in need of another sash window work, they will be my go to."

Customer in Greater LondonWhich? Trusted Traders5.0 rating

Detailed reviews

Customer in Greater London5.0 / 5

We had new bay and sash windows from Core Sash. All the staff we dealt with were professional and polite. They took care to minimise mess and inconvenience and the finishing off work was excellent. We had to pause work due to a leaky roof and this was accommodated without fuss. The finishing off work breathed new life into our rather worn and old plaster work and ledges.

Which? Trusted Traders
Customer in Greater London5.0 / 5

We had 6 sash windows and 1 casement installed in Dec 2019. The installation team arrived on time and were respectful both to us and our property. They kept us informed and cleaned up each day to a reasonable standard. The finish on the windows is fantastic: the final hand coating of paint (by Steven) makes all the difference, and not many companies I had quote offered this. I had previously had 2 sash windows installed by another very large company (LSWC, green logo!) and these windows by Core win hands down - both on appearance, smoothness of operation, and the “making good” of surrounding plasterwork etc. A special shoutout to Steven for that. We did have an issue with on one of the 7 windows we had installed - the architrave used was too large compared to the original and as installed was overlapping the rooms cornicing which spoiled the look of the room. There was a bit of back-and-forth with the company on the matter, necessitating some before and after photos to show the original appearance, but afterwards they did agree to return and fit a smaller architrave at their expense. In an ideal world this would have been picked up by them during the survey and adjustments made ahead of time, but credit to Core, they did return and put it right, so no hard feelings from me and they will be my #1 choice for next time given everything else was top-notch. No experience (yet) of having to call on their warranty.

Which? Trusted Traders
Customer in Greater London5.0 / 5

We had to replace the top sash of one of our windows. After some research and other good reviews I have seen on Which, I decided to go with Core on this. Their sales team is very helpful, answers all of your questions and pays attention to your needs. The new sash production was on time as promised. The job was scheduled and completed on time as promised. They came in and worked so diligently, when they left, there was not even a single dust in the room. And the window was fitted so nicely and is now operating smoothly. Core has done a great job and if I am ever in need of another sash window work, they will be my go to.

Which? Trusted Traders
Customer in Greater London5.0 / 5

The guys at Core Sash Windows provide a really excellent service. We have used them on a couple of occasions now and each time they have gone above and beyond our expectations of the service provided. Their product is top quality and the whole process from start to finish is efficient and streamlined. I highly recommend them!

Which? Trusted Traders
Customer in Greater London5.0 / 5

We had all 6 of our Sash windows of various dimensions replaced by Core and we are very happy with them. They all work well and slide up and down like a dream (you don’t need to be a regular gym-goer). Any slight adjustments or easing we required after the work was completed was immediately tended to with no quibbling. Last, but not least, the noise reduction is amazing as is the energy saving. Last winter we used our heating for less than three hours a day and often just an hour in the morning was sufficient to maintain 20-21C. All the windows are made to detailed measurements and all fitted on arrival. We were constricted by Islington Council Conservation requirements and Core were able to work to those detailed restrictions. Core personnel from our initial contact Dalan Rustemoglu (surveyor), through the office staff to the carpenters and painters, were very professional and helpful. We highly recommend them and now at least 10 other friends and neighbours have, on our recommendation and on viewing the windows, purchased Core windows also. No one has any complaints!

Which? Trusted Traders
Customer in Greater London5.0 / 5

After having a bad experience with a window replacement some years ago, I was delighted when I found Core. From start to finish they were totally professional and helpful & I am very pleased with the windows & door. I will be using them again in the future.

Which? Trusted Traders
Customer in Greater London5.0 / 5

Core Sash Windows replaced several old, single-glazed windows in our house with new, double-glazed windows, both sash and casement. The staff were highly professional and considerate about the need to maintain distance from us in the house in the current circumstances. The work was done on the planned schedule and completed to a high standard. We are very pleased with the new windows, which are similar in appearance to the old ones but now the draught has gone and we also notice the sound-proofing is better than before.

Which? Trusted Traders
Customer in Greater London5.0 / 5

Having used Core Sash once previously, following much research, for new french doors we didn’t hesitate to use them again to replace old upvc windows at the front of the house with original looking sash windows. From start to finish the whole team were utterly professional. The design matched the original Edwardian windows perfectly. The installers were incredible, meticulous, friendly, they took great pride in their work. They left the site spotlessly clean each day. The attention to detail To the workmanship was second to none. The end result is stunning, we will definitely be using them again.

Which? Trusted Traders
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Overview

About Core Sash Windows

Core Sash Windows is a London-based double-glazing company specialising in the replacement and repair of traditional timber-framed windows and doors. We understand that replacement windows and doors are an important investment, and you obviously want to make the correct choice. That is why we offer: • Elegant and traditionally styled products • Attentive customer care • Punctuality and reliability • Considerate workmanship • Convenient and fully comprehensive service • No need for Third Party trades That is why we promise: Our surveys are always performed by experienced carpenters instead of designated sales-people - there's no unnecessary up-selling and no high-pressure tactics. Our FENSA-registered installation service also includes the hand painting of your new products, traditional sand-and-cement pointing joints, and the repair of any damaged plaster. And our traditionally designed windows and doors come with a 10 Year Insurance-Backed Guarantee.

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