Flush Sash Windows
Flush sash windows are the ideal compromise between the benefits of uPVC and the beautiful aesthetic of timber. Timber evokes images of quaint country cottages and of years gone by so it’s easy to see why it’s such a popular look. With a sash that closes into the frame, you can enjoy slim sightlines and a less obtrusive window.

Modern performance with an authentic look
Made of reliable and maintenance free uPVC, our flush sash windows will stay looking as good as new for years to come. With a dual seal for exceptional weatherproofing, your home will stay draught free and comfortable year round.
A+ rated for efficiency, as well as noticing a vast improvement in your warmth, your energy bills should be significantly lower. These windows are able to reach u-values as low as 1.2 to keep your home as insulated as possible. They’re ideal if you live near a busy road too as will keep unwanted noise to a minimum.
Perfect for conservation areas and traditional homes
Even up close, these windows are practically indistinguishable from real timber. This makes them ideal for period homes and those in conservation areas. They will also suit contemporary homes too with a wide range of colours and hardware to personalise them your own way.
Available in 26 colours including Irish Oak, Chartwell Green and Anthracite Grey, you can truly create your own style. With a durable wood grain coating, your colour won’t need repainting and has a 10 year guarantee.


Enjoy the heritage look in your home with flush sash windows
Choose from mechanical or welded joints as well as Georgian bars. With PAS 24 approved multipoint locks, these windows will keep your home secure as well as stylish. Traditional ironmongery, such as the popular monkey tail handle, is available to complete the heritage look. You can truly bring an authentic feel to your home with these beautifully designed flush sash windows.
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Latest reviews
🌟🌟🌟🌟🌟 Definitely a five star rating Absolutely delighted with the new front door! From the initial ordering process to the final fitting, the customer service was outstanding. The Thermotech team was incredibly helpful making the entire experience smooth and stress-free. The quality of the product exceeded my expectations, with exceptional attention to detail.The fitting was done with great precision, and the installers were professional and efficient. I couldn't be happier with the result. Highly recommend Thermotech to anyone.
Carla Higgins
January 3, 2025I would highly recommend Thermotech. I am so pleased with my new extension and windows. I found them experienced and professional from start to finish, with a high skill level in all areas.
Lorraine Bright
October 3, 2024Professional service from start to finish. Attention to detail and quality is Brilliant. Love my new front door. Thank you
Shannon Ryder
September 3, 2024Absolutely brilliant from start to end. Very professional, polite and not an issue having any of the builders in your home, nothing is too much trouble and every last job finished to an excellent standard. Would highly recommend.
Karon Edkins
March 3, 2023I spent a lot of time researching window companies that were both good value,supplied good quality products and had good reviews for their customer service and fitting. I'm glad to say that from that from the time of placing the order to the completion of the installation of our beautiful new windows everything was done as expected and on time. We were informed when the windows would be fitted and the fitters were there on time . They take great pride in their work and left us with quality windows that make a huge difference to our house. I would not hesitate to Recommend Thermotech products who are a local family business.
michael simms
March 3, 2023They fitted us in quickly to replace some patio doors, and the man who came to fit them was so friendly and knowledgeable. They look fantastic, really smart, we're very happy with them. Will definitely use them again in the future if needed.
Harriet Challoner
October 3, 2024Thermotech brilliant yet again! Required some house roof advice and Thermotech called straight over. They arrive on time, never let anyone down and are just amazing. Thermotech are so trustworthy, professional and produce work of a very high quality. I wholeheartedly recommend them to everyone! Thank you ever so much Thermotech for always being so wonderful.
rhian
March 3, 2024Recently had a single storey extension completed by Thermotech. Very professional and helpful throughout the project. Big thanks to Steve for all his hard work. Pleased with the overall finish. Would recommend this company.
Andrea Clements
March 3, 2024Absolutely superb, nothing was too much trouble; they went above and beyond to give us exactly what we wanted. They gave me the 'boot room' I wanted, storage for shoes, dogs stuff and loads more. Warm, cosy and dry. Would definitely recommend to anybody, we will certainly be using them again. Can't thank Thermotech enough x
Wendy Dix
August 3, 2024
🌟🌟🌟🌟🌟 Definitely a five star rating Absolutely delighted with the new front door! From the initial ordering process to the final fitting, the customer service was outstanding. The Thermotech team was incredibly helpful making the entire experience smooth and stress-free. The quality of the product exceeded my expectations, with exceptional attention to detail.The fitting was done with great precision, and the installers were professional and efficient. I couldn't be happier with the result. Highly recommend Thermotech to anyone.
Carla Higgins
January 3, 2025They fitted us in quickly to replace some patio doors, and the man who came to fit them was so friendly and knowledgeable. They look fantastic, really smart, we're very happy with them. Will definitely use them again in the future if needed.
Harriet Challoner
October 3, 2024We have used thermotech on two occasions .the service we recieved from ordering to installation was excellent, Carl and Steve went out of their way to ensure a friendly and helpful experience we would highly recommend them to anyone thinking of having work done 5 star company phil&rose thompson
Phil Thompson
October 3, 2024I would highly recommend Thermotech. I am so pleased with my new extension and windows. I found them experienced and professional from start to finish, with a high skill level in all areas.
Lorraine Bright
October 3, 2024Professional service from start to finish. Attention to detail and quality is Brilliant. Love my new front door. Thank you
Shannon Ryder
September 3, 2024Absolutely superb, nothing was too much trouble; they went above and beyond to give us exactly what we wanted. They gave me the 'boot room' I wanted, storage for shoes, dogs stuff and loads more. Warm, cosy and dry. Would definitely recommend to anybody, we will certainly be using them again. Can't thank Thermotech enough x
Wendy Dix
August 3, 2024Thermotech brilliant yet again! Required some house roof advice and Thermotech called straight over. They arrive on time, never let anyone down and are just amazing. Thermotech are so trustworthy, professional and produce work of a very high quality. I wholeheartedly recommend them to everyone! Thank you ever so much Thermotech for always being so wonderful.
rhian
March 3, 2024Amazing service!! Came out and measured up after a break in into our showroom, made it secure. Then came within Two days and fitted new glass. Even cleaned up all the mess from the break in. Would recommend to anyone
marc potter
March 3, 2024Cannot recommend highly enough - excellent. Karl responded to queries straightaway - great customer service, extremely knowledgeable. A fantastic installation experience. Steve is a highly skilled professional fitter with amazing attention to detail and exceptional quality of work. Everything was cleared up and left immaculate afterwards. Nothing is too much trouble. A huge thank-you to both.
Duncan Kew
March 3, 2024Recently had a single storey extension completed by Thermotech. Very professional and helpful throughout the project. Big thanks to Steve for all his hard work. Pleased with the overall finish. Would recommend this company.
Andrea Clements
March 3, 2024
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