Better compression performance
Long-term compression set recovery to 90% of original shape.
Find the right seal for your application
Search by SKU code or category to find the right seal for your application.
A century of fenestration sealing expertise.
The best-in-class polyurethane foam seals for uPVC windows and doors
Schlegel supplies uPVC windows and doors manufacturers with a full portfolio of gaskets and weatherseals, including Q-LON polyurethane foam, all backed by over a century of fenestration sealing expertise. Beyond aluminium windows and doors, Q-LON composite gaskets are also proven across sectors including construction, transport and HVAC.
- Colours
- Range Overview
- Downloads
Standard and extended colour options for uPVC seals
Q-LON gaskets for uPVC applications are available in a wide range of colours via the weather-resistant embossed polyethylene outer liner. They include brown, white, black, silver, beige, light oak and further colours available on request.
Standard
Black - Standard RAL 9005
Brown - Standard RAL 8019
White - Standard RAL 9003
Silver - Standard RAL 7001
Product Specific
Beige - Extra RAL 1001
Fawn Brown - Extra RAL 8007
Graphite Grey - Extra RAL 7024
Light Grey - Extra RAL 7035
Light Oak - Extra RAL 8003
Pebble Grey - Extra RAL 7032
Pure White - Extra RAL 9010
Sealing products for every uPVC window, door and shutter application
Schlegel's uPVC sealing range covers casement windows, tilt-and-turn windows, entrance doors, patio doors, sliding doors and roller shutters. The table below maps each product family to its primary application.
Download the full Schlegel uPVC sealing product brochure, technical datasheets and Q-LON specification guides. All documents are available in PDF format. Contact the Schlegel technical team for bespoke profile drawings and sample kits.
Key Benefits
Effortless glide
Low friction liners suitable for sliding door applications
Performance reliability
Minimal stretch during installation for minimal creep back over time
Thermal conductivity
Unrivalled thermal performance (0.04 W/mk at 0.ºC) to help with energy savings
Quieter internal environments
Leading sound reduction from extensive testing for outstanding acoustic performance
Paint and stain proof
The outer film is not altered by paints, detergents and colourants
Q-LON: the specification gasket for uPVC casement and entrance doors
Q-LON is Schlegel’s polyurethane foam gasket with a weather-resistant embossed polyethylene outer film. It inserts directly into the groove of a uPVC sash or frame without adhesive, creating a compression seal that blocks air, water and noise infiltration. Q-LON gaskets are available in standard and fire-retardant formulations and are compatible with uPVC, timber and aluminium frame systems.
Custom sealing solutions for uPVC fabricators and OEMs
Schlegel works directly with uPVC window and door fabricators to design dedicated sealing solutions for non-standard profile grooves and specialist applications. Manufacturing facilities operate in the UK, Spain, Germany and Belgium, allowing short lead times for European OEM supply. Sample kits and technical datasheets are available on request from the Schlegel specification team.
Proven in other sectors
As well as uPVC windows and doors, Q-LON composite gaskets are also proven across a wide range of sectors and applications, from airtight, fire-rated sealing for insulated wall panels and glazed partition systems, to window and door sealing in buses, trains, yachts and construction vehicles, as well as reducing conditioned air loss, dampening mechanical vibration and protecting outdoor HVAC units from water infiltration and UV degradation.
Common questions about Schlegel uPVC window and door seals
Find answers to the most frequent questions from uPVC fabricators, installers and specifiers about Schlegel's gasket and weatherseal range.
Q-LON polyurethane foam gaskets are the standard specification for uPVC casement windows. They insert into the frame groove without adhesive and are available in multiple profile sizes to suit different rebate dimensions.
Yes. Q-LON Fire Retardant gaskets are classified to EN 13501-1, Class E. They are designed to slow flame spread and reduce dispersal of flammable material in fire-rated door and window applications.
Yes. Q-LON seals can be overpainted or stained for colour matching without affecting sealing performance. The Aquamac range is impervious to paint and stain, making it suited to maintenance programmes on installed frames.
Yes, Q-LON products are gauranteed for 10 years to provide customers with complete peace of mind.
Schlegel supplies three purpose-built tools to support professional Q-LON fitting. The Q-LON Mitre Cutter produces clean, accurate corner cuts. The Q-LON Insertion Roller seats the seal uniformly into its groove. The Q-LON Overlap Insertion Roller handles overlap joints where two seal lengths meet.
Downloads, Accreditations & Related Products
Discover related products, access technical documentation and accreditations, and find out how Schlegel's 10-year guarantee gives you added peace of mind.
Q-LON Seals - Timber Window & Door Seals
High-performance Q-LON polyurethane foam seals engineered specifically for timber window and door frames.
Find Out More
Q-LON Seals - Shutter & Partition Gaskets
Precision-engineered Q-LON foam seals for roller shutters, internal partitions and dividing systems across aluminium, PVC and timber frames.
Find Out More
Q-LON Seals - Interior Application Seals
Schlegel Q-LON extruded seals for internal doors, furniture and window covering products. Engineered for acoustic control, dust exclusion and long-term compression recovery.
Find Out More
Q-LON Seals - Aluminium Window & Door Seals
Schlegel Q-LON polyurethane foam seals for aluminium window and door frames: tested to EN 12365, built to perform.
Find Out More
Aquamac or Q-LON? Schlegel's polyurethane foam window and door seals explained
Same Schlegel seal, two names. Find your equivalent product code and order genuine Q-LON direct from the manufacturer.
Find Out More
Q-LON Seals - Universal Application Seals
Surface-fit seals that perform on universal surfaces such as timber, aluminium and uPVC without frame modification.
Find Out More
Resources
Find all the information you need at your fingertips for Q-LON, brush pile and extruded seals.
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Brochures
Explore Schlegel brochures and accreditation certificates to learn more about our products and manufacturing standards.
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Get in Contact
Contact us do discuss every aspect of our sealing solutions for windows and doors.
Latest News
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Find out about our latest product launches, technical updates and industry news from Schlegel and the wider Quanex group.
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Technical information, brochures and product data sheets
Access the full Schlegel technical library including product data sheets for Q-LON, brush pile and extruded seals, downloadable brochures covering EN 12365 compliance, and installation guides for timber, aluminium and uPVC applications. All documents are available to download free of charge.