The Honest Truth
We make sash windows for a living. But we believe you deserve the full picture before spending your money. Here are 9 genuine reasons not to buy — and what nobody else will tell you.
This is true. A timber sash window costs significantly more than a PVC equivalent. Depending on size and specification, you could be looking at 2–3 times the price. If your budget is tight and you need windows now, PVC is the rational choice on paper.
But here's what the PVC salesman won't mention: PVC windows have a lifespan of 20–25 years. After that, the entire frame goes to landfill — PVC is not meaningfully recyclable in the UK. In those 25 years, the seals will fail, the mechanisms will stiffen, and the plastic will yellow and become brittle.
A properly maintained timber sash window lasts 60–100+ years. You replace components, not the entire window. Over a 50-year period, timber sash windows cost less per year than PVC — and they add 5–10% to your property value in London's conservation areas, while PVC windows can actually reduce it.
Fair point. Timber is a natural material and it does require periodic attention. If you want to install windows and forget about them completely, timber is not for you.
However, "maintenance-free" is a marketing myth. PVC windows still need their mechanisms oiled, seals checked, and handles replaced. The difference is that when PVC fails, you replace the whole unit. When timber needs attention, you repaint — and modern microporous paint systems last 8–12 years between coats.
With Accoya timber and modern Sikkens or Teknos paint systems, a sash window can go a decade without repainting. A single repaint costs a fraction of a full window replacement. Maintenance is not a burden — it's the reason your windows will outlive you.
From a distance, perhaps. PVC manufacturers have improved their woodgrain foils and proportions significantly. If you're viewing from across the street, you might not notice.
But step closer. Touch the frame. Feel the difference between warm, smooth timber and cold, hollow plastic. Look at the joints — PVC is welded at the corners, creating that telltale shiny ridge. Timber is jointed with mortise and tenon, invisible and clean. Look at the glazing bars — PVC bars are stuck on top of the glass, a flat strip pretending to be something it isn't. Timber bars are structural, holding individual panes, creating genuine shadow lines.
Conservation officers can tell the difference instantly — which is why PVC is rejected in conservation areas across London. Your neighbours can tell. Estate agents can tell. And most importantly, you can tell — every time you open your window and feel timber instead of plastic under your fingers.
If your sash windows are draughty, they're not working properly. This is like saying cars are unreliable because your 1987 Ford Escort broke down. Old, unmaintained sash windows are draughty. New ones are not.
Modern timber sash windows include brush-pile or compression draught-proofing on all moving parts, slimline double glazing with argon gas fill, and can achieve U-values as low as 0.8 W/m²K with Passive Glass — that's better than many brand-new PVC windows on the market.
A new double-glazed timber sash window with proper draught-proofing is as airtight and thermally efficient as any modern window system. The difference is that it also provides natural ventilation when you want it — something a sealed PVC unit struggles to do without mechanical vents.
If your idea of modernity is white plastic frames and tilt-and-turn mechanisms, then yes — sash windows aren't for you. Go with aluminium or PVC and enjoy the contemporary aesthetic.
But take a walk through Chelsea, Notting Hill, Belgravia, Mayfair, Holland Park, Kensington. The most expensive homes in London — properties worth £3 million, £5 million, £15 million — all have timber sash windows. Every single one. The wealthiest, most design-conscious buyers in the world choose sash windows. Not because they're old-fashioned, but because nothing else communicates the same level of quality, permanence, and understated wealth.
There's a reason estate agents photograph the windows. There's a reason architects specify them on high-end renovations. There's a reason that when someone buys a period home and rips out the PVC to put timber back in, the neighbours notice — and the property value jumps.
You don't buy sash windows because they're trendy. You buy them because they make your home feel like it belongs — like it was always meant to look this way. That's not old-fashioned. That's confidence.
Sash windows are not old-fashioned — they're timeless. A Rolex uses a mechanical movement designed centuries ago. A Bentley uses leather and wood. The homes that hold their value in London are the ones that keep their character — and nothing defines a London home like its sash windows. Ask any estate agent what adds more kerb appeal: a new PVC window or a beautifully finished timber sash. The answer is always the same.
You're right — nobody buys a window to stroke it. But here's something you won't understand until you experience it: the difference between touching a PVC frame and a timber frame is the difference between a plastic steering wheel and a leather one. Both do the same job. One makes you feel like you're driving a rental car. The other makes you feel like you're home.
PVC is cold in winter and clammy in summer. It's hollow — knock on it and it echoes. Over time it yellows, scratches, and develops that unmistakable cheap-plastic look that no amount of cleaning can fix.
Timber is warm to the touch year-round. It has weight, solidity, texture. When you open a timber sash window — when you feel the smooth slide of a properly balanced sash on lead weights, the gentle resistance of the cord, the quiet thud as it meets the parting bead — there's a satisfaction that no plastic mechanism can replicate.
It's the same reason people choose hardwood floors over laminate, a real fireplace over a gas insert, a solid oak table over IKEA flatpack. You live with your windows every day. You see them, you touch them, you open and close them hundreds of times a year. That daily experience matters more than you think.
Walk into a house with timber sash windows and you feel it immediately — there's a warmth, a solidity, a sense that someone cared about this home. Walk into a house with PVC and it feels… functional. Adequate. There's nothing wrong with adequate — but if you're spending money on your home, you might want more than that. Your home is the biggest investment you'll ever make. It should feel like it.
This is actually true for many London homeowners. If you live in one of London's 1,000+ conservation areas — and chances are you do, because they cover huge swathes of the city — your local planning authority will almost certainly require timber sash windows. PVC applications in conservation areas are routinely refused.
So yes, in many cases it's not a choice. It's a requirement. And that feels frustrating, especially when PVC is cheaper and easier.
But stop and think about why conservation areas exist. They exist because someone — decades ago — decided that your street, your neighbourhood, your row of Victorian terraces was worth protecting. Worth preserving. They looked at the sash windows, the brickwork, the proportions, and said: this matters. Don't let anyone ruin it.
That protection is the reason your street looks the way it does. It's the reason your home has character. And honestly? It's the reason your property is worth what it's worth. Properties in conservation areas command a premium precisely because the area looks good — and it looks good because everyone is held to a standard.
The "requirement" to install timber sash windows isn't a punishment — it's a quality guarantee applied to your entire neighbourhood. It protects your property value, your street's character, and the architectural heritage that makes London unlike any other city. When your neighbour installs cheap PVC, it drags the whole street down. When everyone maintains timber, everyone benefits. You're not being forced to buy timber — you're being protected from a race to the bottom.
You're right — choosing timber over PVC won't save the planet single-handedly. But if you care even slightly about your environmental footprint, the numbers are worth knowing.
PVC production releases dioxins — among the most toxic chemicals known to science. PVC cannot be effectively recycled in the UK and takes over 300 years to decompose in landfill, slowly releasing microplastics into the soil and water. Aluminium smelting is one of the most energy-intensive industrial processes on earth — producing a single tonne of aluminium generates roughly 12 tonnes of CO₂.
Now consider timber. A single mature tree absorbs approximately 22kg of CO₂ per year. The timber in your sash windows isn't just carbon-neutral — it's carbon-negative. That carbon stays locked in the wood for the entire lifetime of the window. A set of timber sash windows for a typical London terrace locks away the equivalent of what a car produces driving 2,000 miles.
Accoya timber — one of the premium options we use — is made from sustainably grown pine from FSC-certified forests. For every tree harvested, several more are planted. The modification process uses non-toxic acetic acid (essentially vinegar). The result is a material that is rot-proof, dimensionally stable, and has a carbon footprint that is a fraction of PVC or aluminium.
The UK government's Net Zero 2050 strategy specifically encourages the use of timber in construction. Building regulations are tightening. The direction of travel is clear — the future is low-carbon, and timber is already there.
Timber is the only structural building material that absorbs CO₂ rather than producing it. Your sash windows are literally a carbon store — locking away greenhouse gases for 60, 80, 100+ years. Our lead weights are 100% recycled. When a timber window eventually reaches end of life, the wood is biodegradable. No landfill, no microplastics, no toxic incineration. If every home in London replaced its PVC with timber, the carbon savings would be measured in hundreds of thousands of tonnes. Your windows won't save the planet alone — but they're on the right side of the equation.
If your current windows keep the rain out and you're happy with them — don't buy new ones. Seriously. The most sustainable window is the one you already have. If your existing timber sash windows just need draught-proofing, refurbishment, or a repaint, that's always the better option than replacement.
We will always tell you this honestly. We would rather repair your windows than sell you new ones you don't need. That's not marketing — it's how we operate. If your windows can be saved, we'll say so.
You should buy new sash windows only when your existing ones are beyond economic repair — when the frames are rotten, the sashes are warped, or single glazing is costing you hundreds in heating bills. When that time comes, you want someone who will be honest about what you need — not someone who just wants to sell you the most expensive option.
The Verdict
If you want the cheapest option — no. If you want zero maintenance — no. If you don't care how your home looks or feels — definitely no.
But if you live in a period home, if you're in a conservation area, if you appreciate craftsmanship, if you think long-term, if you want windows that feel warm under your hand and add real value to your property — then there is nothing else that comes close.
Timber sash windows are carbon-negative. They last three to four times longer than PVC. They're the only window type that provides natural dual ventilation. They're required in conservation areas because they're the standard everything else is measured against. They feel solid, warm, and real — because they are.
The real question isn't "why should I buy sash windows?" It's "why would I buy anything else?"
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