Casement Windows
We supply casement windows suitable for most property types, installed across Essex and South East England. Our range includes chamfered contemporary and traditional ovolo replicating timber frames. All products are tested for energy efficiency and security, BFRC-rated with a 10-year guarantee. Installations are carried out by factory-trained teams, high-security hardware, backed by 38 years’ experience.
Sash Windows
We have been supplying high-performance windows and doors since 1987. Our sliding sash windows serve customers across Essex and the South East of England. They replicate the appearance of traditional timber frames with modern sliding functionality and materials. We deliver high-quality solutions that combine a traditional aesthetic with contemporary performance for domestic and commercial properties.
Flush Windows
We supply high-performance Flush Windows designed in modern low-maintenance uPVC to bespoke sizes Essex and South East England. flush design sits within the frame, echoing early nineteenth-century timber windows for heritage properties. Double and triple glazing with five-chamber uPVC frames ensure thermal performance. Eighteen foiled finishes and dual-colour options with enhanced security features included are
Tilt & Turn Windows
Since 1987, we have supplied high-performance windows and doors, including tilt and turn windows. Suitable for low, medium and high-rise buildings, popular with domestic and commercial customers in Essex nearby. We supply tilt-and-turn and tilt-only windows with advanced locking mechanisms and varied sizes options. Energy-efficient windows come with 10-year guarantee for complete peace of mind.
UPVC Doors
We supply high-quality uPVC doors across Essex and South East England. Our range includes smooth uPVC and grain-effect foil finishes, with front and back doors designed to complement your windows. Customers can choose direct replacements or new designs to enhance and transform their property's appearance. We also provide thresholds, decorative glass and door furniture.
Patio Doors
We offer sliding patio doors designed to enhance your home’s appearance while maintaining warmth and security. Our doors allow natural light in while preventing heat loss, supported by energy-efficient glazing. Each installation is fitted with a robust six-hook locking system for added security. With extensive experience, we ensure reliable, high-performance solutions that improve both security and aesthetics.
Composite Doors
We supply high-performance composite doors designed to create an excellent first impression. Based in Wickford, Essex, we offer installations locally and trade supply across South East England. Our doors are crafted with precise proportions and a traditional timber appearance. We combine modern materials for improved energy efficiency, safety, and security throughout our range.
French Doors & Windows
We provide high-quality French doors and windows for properties, with supply and installation services. Serving applications in rooms and conservatories across properties in Essex and South East England. Designs include inward or outward-opening French door styles. We offer sidelites to enhance light and access openings. Our range includes multiple window options and finishes since 1987.
Conservatories
We provide conservatory design and manufacturing services for properties across Essex and South East England. Our experienced team guides clients from consultation through design and regulatory submission processes. We offer modern and traditional styles including lean-to, Victorian, gable, Edwardian, Loggia, bespoke. Each project delivers a practical, elegant conservatory tailored precisely to individual requirements.
Jul 12, 2025
The catch on my bedroom window wouldnt work so had to keep it closed in this hot weather. I called in to our local office and had the problem fixed within days. The staff could not have been more helpful or pleasant. A reasonable price too. There is so much poor service and overcharging these days its a very pleasant surprise to deal with Thermaseal. I should add that the window in question was installed by them many years ago. I expected a new window would be needed but thankfully not. A credit to the quality and durability of their product, I would say. Thanks again Thermaseal.
Sep 29, 2021
I just wanted to say how incredibly impressed I am. The door handle had broken on our bifold door and we were unable to lock it, my husband called this morning and by this afternoon someone has been out and fitted a new one!! Thanks great service
Jul 24, 2021
It was about 5 years ago now that Thermaseal replaced all our aluminium windows and doors with white upvc windows and doors. I heartily recommend their products - they are of very high quality and look as if they were fitted yesterday. Their fitters are very experienced and friendly and professional. I am pleased to recommend a local business. Their shop has been in Billericay High Street for many years and their main office in Wickford carries a great selection of doors too. I think they are priced very fairly too. We got several quotes to compare.
Its beginning to look a lot like Christmas.
We have re-opened! Our wickford showroom is open for customers to view our range of WIndows and doors, please call 01268 561717 to arrange an appointment.