What are Sash Windows?
Sash windows are a traditional style of window commonly found in older UK properties. They consist of two sliding panels or ‘sashes’ that move vertically in side channels. The sashes allow the window to be opened in various configurations for ventilation. Sash windows are made from wood, metal or PVC. The counterbalance mechanism allows the sash to be held in position when opened.
Common styles of Sash Windows:
Sash windows come in a variety of styles that offer different aesthetic and functional benefits. The core sash window types found in British homes include the single-hung, double-hung, triple, York, and bow sash. The single-hung is the simplest and most affordable option, with one sliding upper panel. Double-hung sash windows are the most popular and practical, providing two independently operating sashes. For maximum flexibility, triple sash windows feature three vertically sliding panels to allow multiple opening configurations. The horizontal sliding York sash enables wide uninterrupted views when fully open.
For added character, bow sash windows have an elegant curved bay shape. The style chosen impacts the cost, complexity, ventilation options, and period appeal.
Single-hung sash window:
The single-hung sash window has one sliding upper panel and a fixed lower panel. This simple style is the most affordable sash option. The moving top sash allows ventilation while the lower section remains securely closed. Single-hung sash windows can have single, double or triple glazing. They provide basic functionality without the cost of double sashes.
- One sliding upper sash panel above a fixed lower panel
- Allows top sash to be opened for ventilation while lower section remains closed
- Variations include half sash (lower panel split horizontally) and asymmetric sash (upper and lower different sizes)
- Simplest and most affordable sash window option
- Can have single, double or triple glazing
Double-hung sash:
The double-hung sash is the most popular style in the UK. It has two sliding sash panels that operate independently from each other. Both the bottom and top sections can open and close, enabling excellent control of ventilation and views. Double-hung sash windows offer the most flexible configurations for managing light and airflow.
- Two sliding sash panels that operate independently from each other
- Bottom and top sections can both open and close enabling better control of ventilation
- Most versatile for controlling airflow, light and views
- Range of configurations e.g. both open fully, one open other closed, top open a little etc
- Most popular and flexible sash window style in the UK
Triple sash:
Triple sash windows feature three vertically sliding panels. Each section – the bottom, middle and top – can open independently. This enables maximum flexibility for ventilation, though triple sashes can be heavy and tricky to operate at height. The three sashes provide advanced options for airflow but come at increased cost and complexity
- Three sliding vertically operating sash panels
- Enables bottom, middle and top sections to open independently
- Maximum flexibility for ventilation and view options
- Difficult to operate for some when at height
- Heavier and more complex sash mechanisms
- Uncommon and more expensive than single or double sash
York sash:
Distinct from standard vertical sashes, the York sash has panels that slide horizontally. When fully opened, these can enable wider unobstructed views. However, York sashes are vulnerable to wind damage when open and can be awkward to operate at height. This regional style is most synonymous with Yorkshire architecture.
- Sash panels slide horizontally rather than vertically
- Can enable wider unobstructed views when fully opened
- Vulnerable to wind damage when open
- Operation can be awkward at height
- A regional style most synonymous with Yorkshire
Bow sash windows:
The bowed bay window shape creates a focal point and sense of space. Bow sash windows can feature curved double or triple sash configurations. Their complex installation and bespoke glazing comes at increased cost. But the aesthetic impact of the elegant curved bow sash is popular in period homes.
- Sash windows with curved bay shape
- Bowed outwards to increase light and create space
- Can have curved double or triple sash configurations
- Popular for period properties including Victorian homes
More complex installation and glazing requirements
Sash window materials
Sash windows are crafted from wood, metal or PVCu, each with their own aesthetic qualities, durability, insulation performance and cost considerations.
Wood Sash Windows:
Wood is the traditional material for sash windows. It provides an attractive, classic aesthetic that perfectly suits period homes. Hardwoods like oak are extremely durable, though require more maintenance than modern materials. Regular painting or staining is needed to protect the timber from weather damage. Choosing sustainably sourced, FSC-certified wood ensures environmental sustainability.
Metal Sash Windows:
Metal sash windows offer enhanced durability and low maintenance. Aluminium is lightweight yet robust, while steel is incredibly strong and secure. Metal framing enables the recreation of fine glazing bar and Georgian bar designs. Thermal performance can be improved with powder coated finishes. However, metal conducts heat more than wood or PVCu, so is less insulating. Condensation and noise transmission may also be issues.
PVCu Sash Windows:
PVCu (uPVC) is popular for modern sash windows as it doesn’t require painting and has excellent thermal efficiency. It is cheaper than wood or metal but lacks the finesse and character. The plastic appearance and narrower frame dimensions may not suit all period properties aesthetically. However, with realistic woodgrain finishes and panel detailing, PVCu can emulate traditional styling while being completely maintenance free
Sash Window Costs
Sash window prices can vary enormously based on the frame material, glazing, and accessories chosen. Basic PVCu sashes can be under £350 each, while premium solid wood box sash windows with heritage features can cost over £2,000 per window installed. Refurbishing existing sash windows is the most cost-effective option.
To replace the sash windows on a typical 3 bedroom house, the total cost could range from £5,000 for basic PVCu sashes up to £15,000 for high-end wooden windows, assuming 10-12 standard sized windows.
Comparison of sash window material costs:
Material – Indicative Cost Per Window (installed)
PVCu – £350-£500
Aluminium – £500-£800
Hardwood – £800-£1,500
Solid Oak – £1,500-£2,500+
Key factors: PVCu is the most budget friendly material, while natural solid wood sashes with finer detailing and sustainability credentials attract premium pricing.
Comparison of sash window style costs:
Style – Indicative Cost Per Window (installed)
Single-hung – £350-£600
Double-hung – £500-£950
Triple sash – £800-£1,200
York sash – £550-£950
Bow sash – £1,000-£2,500+
Key factors: Single-hung is the simplest and most affordable. Triple and bow sash windows require more materials, complex installation and glazing, increasing costs.
Things to check when replacing Sash windows
Retain original styling and proportions:
When replacing old damaged sash windows, it’s important to carefully remove the existing frames and measure everything precisely, rather than relying on standard sizes. The position and shape of the original windows will have been carefully designed to balance the property’s facade. Replicating the original symmetrical window patterns and glazing bar layouts maintains the period character of the building. Subtle details like sash horns – the protrusions on the bottom rail – authenticate the heritage aesthetic. Taking the time to faithfully match the styling creates new sash windows that look like they belong in the structural opening, rather than sticking out as obvious replacements. Your joiner can create purpose-built sashes based on the measurements of your original windows. This attention to accuracy and proportions ensures the new windows blend harmoniously.
- Carefully measure existing sash sizes and replica the original dimensions precisely
- Match the number of panes and glazing bar configurations
- Retain heritage detailing like sash horns for an authentic look
Choose appropriate materials:
The frame material greatly impacts the look, performance and maintenance needs of your new sash windows. Natural hardwoods like oak suit traditional properties, with their warm tones and richness adding character. But they require regular repainting or staining to protect the wood. Durable, weather-resistant PVCu is the lowest maintenance option, with no need for painting and excellent thermal efficiency. Yet some sacrifice period authenticity for plastic’s affordability. For heritage aesthetics combined with minimal upkeep, aluminium or sustainably sourced FSC timber can provide the ideal solution. Seek windows made from environmentally responsible materials – whether oak from well-managed forests or PVCu produced from recycled plastic waste. The right material choice extends your sash windows’ lifespan and reduces maintenance, while harmonising with your home’s period features.
- Select durable, weather-resistant materials that suit the property’s age and style
- Hardwoods like oak add character but need maintenance. PVCu is low maintenance
- Check sustainability credentials e.g. FSC certified wood from responsible sources
Seek specialist expertise
Finding a reputable sash window supplier is crucial for a successful installation. Seek recommendations and reviews to identify specialists experienced in heritage restorations and replacements. A thorough on-site evaluation by experts well-versed in original features is invaluable. Make sure your chosen firm takes the time to examine your existing sash windows and understand what needs to be precisely replicated. Specify heritage-accurate details like slender glazing bars, deeper bottom rails and reproduction period hardware to capture the aesthetics. Complex styles like bay sashes require enhanced joinery skills and certified installers. Entrusting your sash window project to qualified specialists ensures your new windows match the original designs and install correctly first time. Investing in genuine expertise preserves your property’s period charm.
- Find an experienced sash window company that can accurately assess your existing windows
- Specify enhanced heritage features like deep bottom rails, slim glazing bars and period hardware
- Complex sash window styles require certified installation by qualified expert
If you are ready to take the next steps and get quotes for your new sash windows you can head over to our dedicated window quotes page or complete the form below to get your free no obligation quotes.
