Draught-sealing a double-hung sash window is absolutely a job a confident DIYer can do well — with the right kit and a bit of patience. It's also a job where the details matter. Here's an honest guide to help you decide which path is right for your windows.
The DIY route: when it's a great fit
The Sellaseal approach isn't a strip of stick-on tape — it's the real professional method, packaged so you can do it yourself. That means you're pulling the sashes out, fitting proper timber beads and brush seals, sorting out the meeting rail, and re-cording where needed.
DIY is a great fit if you:
- Are comfortable pulling a window apart and putting it back together
- Have basic tools and an afternoon per window (allow more for your first one)
- Have painted timber double-hung windows on cords
- Want to save on labour and enjoy a satisfying restoration project
What's involved, roughly:
- Remove the beads and take the sashes out
- Replace worn/snapped sash cords so the window runs smoothly
- Fit the new primed staff and parting beads with brush seals
- Seal the meeting rail with the track and brush
- Reassemble, and enjoy a window that glides shut and seals tight
The Double-Hung Window Draught Sealing Kit includes everything for this — staff bead, parting bead, twin-fin brush seals, meeting-rail track and premium 6 mm sash cord — plus step-by-step instructions, sized for windows up to 2 m × 1 m. There's also a full written install guide online to follow alongside the video.
When to call in Sealasash instead
DIY isn't for everyone or every window. Consider having it done professionally if:
- The windows are painted shut, badly warped, or have rot that needs repair first
- They're heritage or listed and you want zero risk to original joinery or glass
- The windows are larger than the kit's range, or use a non-standard balance system
- You've got a whole house of windows and want it done fast and consistently
- You'd simply rather not pull your windows apart
This is Sealasash's core service: we get the window working, seal the leakage paths, and keep everything discreet and sympathetic to the original. It's the same method behind 25,000+ sealed windows and a 4.9-star rating from 180+ reviews.
A word on avoiding regret
Whichever way you go, two things separate a good outcome from a frustrating one:
- Fix the function first. A sealed window that doesn't run smoothly is a window you'll fight with every day. Sort the cords and the movement before you seal.
- Use products designed to move with the sash. Foam tape and rubber strips fight a sliding window and lose. Brush seals and proper beads are what last.
Get those right — yourself or with us — and your old double-hungs will be warmer, quieter and smoother than they've been in decades, while still looking exactly as they should.
Ready to start? Grab the DIY kit — or book a Sealasash quote if you'd like it done for you. Either way, you keep your original windows.