Core Sash Windows

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.

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.

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.

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!

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!

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.

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.

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.

Core Sash windows replaced the sashes in my front-room bay of four windows. I was very pleased with their services. Sean and the team were helpful and realistic throughout, and communication was good as the work progressed. They stuck to their proposed timetable, the team were very careful with the property, protected the rest of the room they were working in and cleaned away each evening. The workmanship was excellent, from the carpentry to the painting. Cost wise they were in line with other quotes, but I'd have no hesitation in recommending them given the quality product and the overall service.

Core Sash Windows were recommended to me when I had to have four attic windows replaced. I was very happy with their work so when I decided to have the rest of the windows in the house replaced I asked them to come back. They built and fitted an additional thirteen sash windows and two casements. They were thorough, friendly and helpful throughout. The windows are beautiful, work perfectly and were extremely well finished. The fitters were a pleasure to have in the house and they left everything in excellent condition. I have no hesitation in recommending them.

Core sash windows did an amazing job on replacing my bay windows. Everyone in the team were friendly, efficient and easy to contact. They are such good quality windows and the installers and decorators had great attention to detail. Tim even organised for additional paint to be dropped by for touch ups when I mentioned the room was still being renovated. I’ll be getting them to do all the windows in the flat and have recommended them to friends. Thanks Core!

I used Core to replace 2 windows. The quality of the windows is excellent and the carpenters and painter were hard working and competent. They were all pleasant to have around the house and cleaned up perfectly. The company administration is very efficient. I am already looking to get more windows replaced by Core.

We used Core Sash Window on 3 separate occasions for a total of 8 windows and we are very satisfied with the end result. Communication was easy and they responded quickly when problems occurred. They do need careful managing.

I could not have asked for a better outcome when having full box replacements for my sash windows (based in London Fields, Hackney). Work was carried out to a high standard, efficiently and throughout installation the property was kept clean and protected from the risk of dust and potential damage. Special thanks go to Tim and Nicu who were brilliant. I have no hesitation in recommending Core or using them again in the future.

Throughout the process everyone we met and spoke to were knowledgeable, professional and completed the work to a very high standard. Responsive and friendly from start to finish. The window itself was fitted and finished neatly, work was very tidy and quick, and looks great! Would definitely recommend.

Tim and the team were professional, efficient and responsive. They were flexible with our schedule and we very really impressed with the quality of their work. Highly recommended.

Had new French Doors installed and the fitters were efficient, took great care to isolate disruption and cleaned up perfectly. The decorator who came the next day was meticulous and again left no mess at all. Not all companies will make good and redecorate around their work like this.

I live in a listed building so our design constraints are very tight. I'm very pleased with the service and the product. Incredible work from the whole team! Some mistakes were done at the start but what really matters is how well they dealt with it. It's an honest business that cares about their customers. I'll surely be using their services again.

We have had 7 windows replaced by Core Sash Windows, and are absolutely delighted with the work they have done for us. From our initial appointment with Ryan to the actual work days with the window installer (Irmis) and the painter (Andrew), everything has gone smoothly without a hitch. The quality and cleanliness of the work, as well as their professionalism exceeded our expectations. We would warmly recommend them!

Virtually all Victorian sash and casement windows replaced with new double-glazed equivalents. The windows, as delivered, seem to be very high quality and the installation work, which could have been very disruptive, was carried out very efficiently and with maximum consideration for our having rooms to live in. The team were a pleasure to deal with. They cleaned as they went on and helped put back the curtain rails and curtains, not only helping me but ensuring I did not damage up the new windows! The windows are not the cheapest but I don't think they could be faulted for quality or for finish.