After many years working for some of London’s larger sash window companies, I made a decision that changed everything — I started Hartwell Sash. Not because I wanted to run a business. Because I wanted to do the job properly.
Working within large companies, I saw how the pressure of volume and tight schedules affected quality. Jobs were rushed to meet targets. Details were overlooked. The kind of work that takes an extra hour to do properly — the difference between a job that lasts five years and one that needs redoing in twelve months — was quietly set aside.
I understood why it happened. When you have ten jobs booked and a team to manage, shortcuts become routine. But every time I left a job knowing it wasn’t done the way it should be, it sat with me.
Starting Hartwell Sash gave me back something I had lost — control. Control over how long I spend on a job. Control over the materials I use. Control over the standard I hold myself to.
When I draught proof a window, I replace the staff bead and parting bead properly. When I replace sash cords, I replace all four — not just the broken one. When I assess a window, I give you an honest answer about what it actually needs, not what’s quickest or most profitable.
When draught proofing, we also fit a brush seal at the meeting rail — the central gap where the two sashes meet, which is often the biggest source of draughts. Where the existing lock is worn or doesn’t close the sashes tightly, we’ll advise replacing it too — a small detail that makes a significant difference to how well the window seals.
That’s not a selling point. That’s just how the job should be done.
When you book Hartwell Sash, you get someone who has spent years working on period properties across London — Victorian terraces in Hackney, Georgian townhouses in Islington, grand residences in Kensington and Chelsea. Someone who knows what these windows need and takes the time to deliver it.
You also get honesty. If your windows can be repaired, I’ll repair them. If they genuinely need replacing, I’ll tell you that too — and explain why. You’ll never be sold something you don’t need.
We never recommend replacement when repair is the right answer. Your original windows — and your budget — always come first.
Every job is completed the right way — no shortcuts, no rushing, no cutting corners to save time.
Every job is backed by a 5-year workmanship guarantee. We stand behind our work — fully insured, fully accountable.
Free survey, same-day response, no call-out fee.
Honest advice, no obligation.