Claytonrite® Glazing Rubber & Window Seals – Complete Guide
Claytonrite® glazing rubber is a flexible window sealing system designed to securely hold glass or other glazing materials within a panel or frame.
Widely used across classic cars, commercial vehicles, boats, caravans, motorhomes, machinery and specialist glazing applications, Claytonrite® provides a practical solution for installing fixed windows while helping to create a secure, weather-resistant seal.
Claytonrite® is a registered trademark owned by The Seal Extrusion Company Ltd.
At The Seal Extrusion Company, we supply a range of Claytonrite® glazing rubber profiles and accessories in different sizes to suit varying glass and panel thicknesses.
Whether you're replacing an old window seal, restoring a classic vehicle or installing new glazing, this guide explains how Claytonrite works, how to measure your existing window and how to choose the correct profile.
What is Claytonrite®?
Claytonrite® is a type of rubber glazing seal designed to hold a pane of glass securely within an opening.
The rubber profile contains separate channels that accommodate the glass and the surrounding panel or frame.
Once positioned around the window aperture, a separate filler or locking strip is inserted into the Claytonrite profile. This expands and locks the rubber into position, helping to grip both the glazing and surrounding panel securely.
This type of glazing system is particularly useful where a traditional bonded or framed window installation isn't suitable.
What is Claytonrite glazing rubber used for?
Claytonrite glazing seals can be used for a wide range of fixed-window applications, including:
- Classic and vintage cars
- Car restoration projects
- Commercial vehicles
- Agricultural vehicles and machinery
- Boats and marine applications
- Caravans
- Motorhomes
- Horseboxes
- Plant and construction machinery
- Specialist vehicles
- Industrial equipment and enclosures
Because many older vehicles and specialist applications use rubber-mounted glazing rather than modern bonded glass, Claytonrite remains particularly useful when restoring or replacing existing window seals.
How does Claytonrite® work?
A Claytonrite glazing system normally consists of three main components:
1. The glass or glazing material
This sits inside one channel of the rubber profile.
2. The body panel or frame
A second channel fits around the edge of the window aperture.
3. The filler or locking strip
The locking strip is inserted into the Claytonrite profile once the glass and rubber are positioned correctly.
Inserting the filler strip expands the rubber profile and increases the grip around the glass and panel.
This helps create a secure installation and weather-resistant seal.
How do I choose the correct Claytonrite profile?
The most important part of selecting Claytonrite is matching the profile to the dimensions of your application.
You will normally need to know:
Glass thickness
Measure the thickness of the glass or glazing material that will sit inside the rubber.
Panel thickness
Measure the thickness of the metal, fibreglass or other material surrounding the window opening.
Profile dimensions
Different Claytonrite profiles are designed for different combinations of glass and panel thickness.
Do not choose a glazing rubber based only on its overall appearance. Profiles that look very similar can have different channel dimensions.
Always check the dimensions shown on the individual product page against your measurements before ordering.
How do I measure for Claytonrite® glazing rubber?
For the most accurate results, measure using a Vernier/digital caliper where possible.
You should establish:
Glass thickness:
The thickness of the glass or glazing panel.
Panel thickness:
The thickness of the material surrounding the window aperture.
Existing seal dimensions:
If you're replacing an existing glazing rubber, measure the profile wherever possible.
Old rubber can shrink, stretch, compress and become distorted over time, so measurements taken from a very old seal should be compared carefully with the original application.
Top tip
If you're unsure which profile you require, compare the dimensions of your existing seal with the technical drawings and measurements shown on our Claytonrite product listings.
How much Claytonrite do I need?
Measure the complete perimeter of the window opening.
For a rectangular window:
(Width × 2) + (Height × 2) = approximate length required
For example, a window measuring:
800mm wide × 500mm high
would have an approximate perimeter of:
800 + 800 + 500 + 500 = 2,600mm
or:
2.6 metres
We recommend allowing some additional material rather than ordering the exact calculated perimeter, particularly where corners or unusual window shapes are involved.
What is a Claytonrite filler strip?
The filler strip, sometimes referred to as a locking strip or infill strip, is an important part of many Claytonrite glazing systems.
Once the glazing rubber, panel and glass are positioned correctly, the filler strip is inserted into the designated channel.
This expands the rubber and helps lock the glazing system securely into position.
The correct filler strip should be used for the Claytonrite profile you've selected.
How do you fit Claytonrite®?
Installation will vary depending on the profile and application, but the general process involves:
- Check that the glass, panel thickness and Claytonrite profile are compatible.
- Cut the glazing rubber to the required length.
- Position the rubber around the window aperture.
- Carefully install the glass into the appropriate channel.
- Check that the rubber is sitting correctly around the entire window.
- Install the appropriate filler/locking strip.
- Inspect the finished installation to ensure the rubber is seated correctly and there are no obvious gaps or distortion.
Specialist glazing tools and suitable installation lubricants can make fitting considerably easier.
For vehicle, marine or safety-critical glazing, professional installation should be considered where appropriate.
Can Claytonrite be used for classic cars?
Yes. Claytonrite-style glazing seals are commonly used in classic and vintage vehicle restoration, particularly on vehicles manufactured before bonded automotive glazing became widespread.
Applications can include:
- Windscreens
- Rear windows
- Side windows
- Fixed quarter windows
- Specialist vehicle glazing
The correct profile depends on the thickness of both the glass and the vehicle's body panel.
Can Claytonrite be used on boats?
Claytonrite glazing rubber can be suitable for certain marine and boat window applications, particularly fixed glazing installed into a suitable panel.
Correct profile selection and installation are particularly important in marine environments because the window may be exposed to rain, spray, UV and changing temperatures.
Always confirm that the chosen profile is suitable for the dimensions and requirements of your particular application.
Can Claytonrite be used on caravans and motorhomes?
Claytonrite glazing rubber can be used for appropriate fixed-window applications on caravans, campervans and motorhomes.
However, caravan and motorhome window systems vary considerably.
Before purchasing, check whether your existing window uses this type of rubber glazing system and carefully measure the glass and surrounding panel.
What is Claytonrite made from?
The material used depends on the individual profile, so you should always check the specification of the particular product you're purchasing.
Many modern glazing seals use EPDM rubber because it offers good resistance to weathering, ozone and UV exposure, making it particularly useful for external applications.
The material specification for each Seal Extrusions product should be checked on the relevant product page.
Why do old window seals need replacing?
Rubber window seals are continually exposed to environmental conditions.
Over time, an ageing seal may:
- Harden
- Crack
- Shrink
- Split
- Lose flexibility
- Become compressed
- Allow water ingress
- Become difficult to refit after glass removal
Replacing deteriorated glazing rubber can help restore the fit around a window and reduce the risk of leaks.
Can I replace an old Claytonrite seal?
Yes, but identifying the correct replacement profile is important.
Older rubber may no longer retain its original dimensions, so don't rely solely on measuring a stretched or badly deteriorated seal.
Where possible, establish:
Glass thickness + panel thickness + profile dimensions
and compare these measurements against the technical drawing for the replacement profile.
Claytonrite® for Classic Cars, Boats, Caravans & Specialist Vehicles
One of the advantages of Claytonrite glazing systems is their versatility.
At The Seal Extrusion Company, our customers use rubber seals and glazing profiles across a wide range of restoration, maintenance and DIY projects.
Whether you're restoring a classic vehicle, replacing glazing on a boat or trying to identify an ageing window seal, accurate measurement is the key to finding the correct replacement.
Need Help Identifying Your Claytonrite® Seal?
Choosing between similar rubber profiles can sometimes be difficult.
If you're unsure which Claytonrite profile you require, contact The Seal Extrusion Company with as much information as possible about your application.
Useful information includes:
- Glass thickness
- Panel thickness
- Existing rubber dimensions
- Vehicle/boat/application
- Photographs of the existing profile
- Photograph of the window or opening
Our team can then help you identify the most appropriate option from our available range.
Shop Claytonrite® Glazing Rubber
Browse our range of Claytonrite® glazing rubber, window seals, filler strips and glazing accessories.
Claytonrite® Frequently Asked Questions
What is Claytonrite?
Claytonrite® is a rubber glazing system used to secure glass or other glazing materials within a panel or window opening. A locking or filler strip is typically used to expand the rubber and secure the installation.
Who owns the Claytonrite trademark?
Claytonrite® is a registered trademark owned by The Seal Extrusion Company Ltd.
How do I know which Claytonrite seal I need?
Measure the thickness of your glass and the thickness of the surrounding panel. Compare these measurements with the dimensions and technical drawings provided for each Claytonrite profile.
What does the Claytonrite filler strip do?
The filler or locking strip expands the glazing rubber once installed, helping the profile grip the glass and surrounding panel securely.
Is Claytonrite suitable for classic cars?
Claytonrite glazing profiles can be suitable for many classic and vintage vehicle applications where the glass is mounted using a rubber glazing system.
Is Claytonrite suitable for boats?
Certain Claytonrite profiles can be used for suitable fixed marine glazing applications. The correct profile must be selected according to the glass, panel and application requirements.
How much Claytonrite should I order?
Measure the complete perimeter of your window and allow some additional material for fitting and trimming.
Can I order a sample before buying?
Unfortunately we no longer provide samples. If you are unsure, please order a metre and if it is not the correct trim, you can return it.