Best Sash Window Parting Beads for Period Properties: 2025 Expert Review
DR Joinery
Expert Joiner & Restoration Specialist
If your sash windows rattle in the wind or let in a chill, the parting bead is often the culprit. It is the thin strip of timber (or plastic) that separates the top sash from the bottom sash. In many of York's older properties, these beads are painted over, rotten, or simply worn away.
Replacing them is not just about stopping the rattle; it is the most effective stage to introduce draught-proofing directly into the box frame. However, choosing between traditional timber and modern plastic profiles can be confusing for homeowners.
In this review, I will compare three options I have encountered: a budget-friendly plastic carrier system, a robust timber profile for heavy restoration, and a deep-profile timber bead that solves common fitting problems in worn window boxes.
Live in York?
Sash windows stuck or draughty?
Get a free quote for restoration.
Specs vs. The Real World
The Spec: "Friction Fit Installation"
"Manufactures often claim you can simply push the bead into the groove, and it will hold itself in place."
In Victorian properties, the grooves are rarely uniform. They are often clogged with 100 years of paint or widened by rot. You will almost always need to clean the channel out with a router or chisel, and occasionally pin the bead to ensure it stays put.
The Spec: "Plastic vs Timber"
"Plastic is maintenance-free and superior to wood."
Plastic functions well for draught exclusion, but it can look stark and cheap on a heritage facade. Timber beads, when primed and painted properly, offer the same performance but maintain the authentic aesthetic required in conservation areas.
My Top 3 Recommendations
Three options to cover different needs and budgets
Sash Window Plastic Parting Bead – White or Brown, 3m Length (White)
Generic
This uPVC option is a modern solution designed purely for function. It eliminates the need for painting and provides an excellent seal against draughts thanks to the integrated brush pile. Ideally suited for rental properties or windows that are not strictly 'heritage' listed.
The Good
- Rot-proof material requires zero painting
- Integrated brush pile offers excellent draught exclusion
- Flexible fins allow for easier removal when maintaining sashes
The Bad
- Aesthetically incorrect for strict conservation areas
- Can become brittle over many years of UV exposure
Installer Tip:
Because this is plastic, do not force it into a tight groove with a hammer as you might with timber; it will shatter or kink. Clean the groove thoroughly first. If fitting in winter, keep the bead warm indoors until the last minute to prevent snapping.
Priced at £24.95 at the time of writing
Check Price on AmazonSash Window Timber Parting Bead Primed 22mm x 14mm with Brush Pile
Generic
This is a substantial timber bead. Whilst 22mm is wider than a standard parting bead (often used for staff beads or specific wide-box details), the primed finish and quality brush pile make it a solid choice for comprehensive restoration projects where timber integrity is key.
The Good
- Traditional timber aesthetic suitable for period homes
- Pre-primed surface saves significant time on site
- Quality brush pile reduces sash rattle
The Bad
- Dimensions (22x14mm) are non-standard for some parting bead slots - measure carefully
- Requires painting to seal effectively against moisture
Installer Tip:
Check your existing groove width carefully. This bead is 14mm wide, whereas many Victorian grooves are only 8-10mm. You may need to widen the channel with a router, which is a big job unless you are doing a full refurb.
Priced at £26.99 at the time of writing
Check Price on AmazonSash Window Timber Parting Bead Primed 8 x 25 with Brush Pile
Generic
This is the 'go-to' size for most restoration work. The 8mm width fits standard grooves, whilst the generous 25mm depth is a problem-solver for old window boxes where the channel has worn deep over a century of use. It ensures the bead doesn't disappear into the frame.
The Good
- Classic 8mm width fits the majority of Victorian parting bead grooves
- Extra 25mm depth accommodates worn or uneven channels
- Includes carrier and pile for immediate draught exclusion
The Bad
- Timber must be kept dry before top-coating to prevent swelling
- May need planing down if the channel is shallow
Installer Tip:
The 25mm depth is excellent for security. If your groove is shallow, just trim the back edge of the timber with a block plane. It is always better to have too much timber than too little when working on out-of-square boxes.
Priced at £26.99 at the time of writing
Check Price on AmazonFrequently Asked Questions
What is the difference between a parting bead and a staff bead?
Can I replace parting beads without removing the sashes?
Should I use timber or plastic parting beads?
How do I stop my new parting beads from sticking?
Why do you recommend primed products?
Need Professional Sash Window Restoration?
Our team at DR Joinery specialises in Sash Window Restoration across York.
Get a free quote for professional installation.
View Our Sash Window Restoration Service