Casement Window vs Sash Window
Comparison Overview
When comparing Casement Window and Sash Window, several key differences become apparent. In terms of cost, Sash Window are approximately 55% more expensive than Casement Window, with average prices of £550 and £850 respectively. This price difference reflects variations in design complexity, materials, and installation requirements. For energy efficiency, Sash Window offer better thermal performance with an efficiency rating of 0.0%, compared to Casement Window's 0.0%. This translates to potential differences in household energy savings. Casement Window provide superior security features, which is an important consideration for homeowners concerned about safety. Casement Window typically have a lifespan of 20-30 years, while Sash Window last approximately 20-25 years. Casement Window are particularly suitable for Most residential homes and Kitchens and bathrooms, while Sash Window excel in Period properties and Victorian and Georgian homes. Maintenance requirements vary between the two styles, with implications for long-term ownership costs and convenience. Your choice between these window types should ultimately depend on your specific needs, including budget constraints, energy efficiency goals, security requirements, aesthetics, and the architectural style of your property.
Casement Window
A casement window is hinged at the side and opens outward like a door, offering excellent ventilation and unobstructed views.
Sash Window
A traditional window style consisting of one or more movable panels (sashes) that slide vertically or horizontally in the frame.
Average Price
£550
Casement Window
£850
Sash Window
Energy Efficiency
0.0%
Casement Window
0.0%
Sash Window
Security Rating
High
Casement Window
Medium
Sash Window
Customer Rating
4.7/5
Casement Window
4.5/5
Sash Window
Detailed Comparison
Features Comparison
Best Suited For
Casement Window Best For:
- Most residential homes
- Kitchens and bathrooms
- Areas requiring good ventilation
Sash Window Best For:
- Period properties
- Victorian and Georgian homes
- Conservation areas
- Traditional aesthetics
Pros and Cons
Casement Window
Advantages:
- Excellent ventilation
- Good security when closed
- Energy efficient with tight seal
- Easy to operate
- Unobstructed views
Disadvantages:
- Can be caught by wind when open
- Limited size options for very large openings
- Opening mechanism may deteriorate over time
Sash Window
Advantages:
- Traditional aesthetic
- No outward opening space required
- Good for period properties
- Available in various configurations
Disadvantages:
- More complex to manufacture
- Can be drafty in older designs
- Typically more expensive than casement
- Moving parts may require maintenance
Cost Comparison
The table below shows typical costs for Casement Window and Sash Windowin different sizes. Prices include window and installation.
| Window Size | Casement Window | Sash Window | Difference |
|---|---|---|---|
| Small (600 × 900mm) | £385 | £595 | Save £210 with Casement Window |
| Medium (1000 × 1200mm) | £550 | £850 | Save £300 with Casement Window |
| Large (1200 × 1500mm) | £715 | £1,105 | Save £390 with Casement Window |
| Bay/Bow (Custom Size) | £1,375 | £2,125 | Save £750 with Casement Window |
Additional Cost Considerations
Installation Complexity:
Casement Window windows typically are less complex to install compared to Sash Window windows, affecting labor costs.
Long-term Value:
Consider energy efficiency ratings and durability - Sash Window windows offer better long-term energy savings.
Factors Affecting Price
Window Material Options
- uPVC: Most affordable option (1x base price)
- Aluminum: More expensive (1.5-2x base price)
- Timber: Premium option (2-3x base price)
Other Price Factors
- Glazing options (double vs triple)
- Security features and hardware quality
- Property access and installation difficulty
- Regional price variations (higher in London/SE)
Energy Efficiency & Performance
Casement Window Windows
Sash Window Windows
Energy Efficiency Comparison Summary
Both window types offer similar energy efficiency ratings, but may have different strengths in terms of noise reduction, ventilation, and other factors.
About U-Values
U-value measures how well a window prevents heat from escaping. Lower numbers are better - a window with a U-value of 1.2 W/m²K loses less heat than one with 1.6 W/m²K.
Building regulations require new windows to have a U-value of 1.6 W/m²K or lower. Windows with values below 1.0 W/m²K offer excellent thermal performance but typically cost more.
Energy Savings Potential
| Property Type | Casement Window Annual Savings* | Sash Window Annual Savings* |
|---|---|---|
| Small (1-2 bedroom flat) | £79 | £76 |
| Medium (3 bedroom house) | £126 | £121 |
| Large (4+ bedroom house) | £183 | £177 |
*Estimated annual savings when replacing single-glazed windows. Actual savings will vary based on your property's insulation, heating system, and local climate.
Maintenance & Lifespan
Casement Window Windows
Maintenance Requirements:
Medium - hinges and handles require occasional lubrication
Sash Window Windows
Maintenance Requirements:
Medium-High - sliding channels require regular cleaning and lubrication
Maintenance Comparison
| Maintenance Task | Casement Window | Sash Window |
|---|---|---|
| Cleaning | 2-4 times per year | 2-4 times per year |
| Hardware Lubrication | Annually | Annually |
| Seal Inspection | Every 1-2 years | Every 1-2 years |
| Weather Stripping | Replace every 5-8 years | Replace every 5-8 years |
| Professional Service | Every 2-3 years | Every 2-3 years |
Maintenance Tips
Extending Window Lifespan
- Clean tracks and hinges regularly
- Use silicone spray on moving parts annually
- Check and replace weather stripping as needed
- Inspect and repair caulking to prevent leaks
Signs Windows Need Replacement
- Difficult to open or close
- Visible condensation between glass panes
- Drafts even when closed
- Rotting frames or water damage
Security & Safety Features
Casement Window Security Features
Common Security Features:
- Multi-point locking systems
- Reinforced frames for added strength
- Laminated or toughened safety glass options
- Internal beading to prevent glass removal
Sash Window Security Features
Common Security Features:
- Multi-point locking systems
- Reinforced frames for added strength
- Laminated or toughened safety glass options
- Internal beading to prevent glass removal
Security Certifications to Look For
Secured by Design (SBD)
Police-backed initiative that certifies products meeting strict security standards.
BSI PAS 24
British Standards Institute certification for enhanced security performance requirements.
Safety Glass Options
Toughened Glass
Heat-treated to make it 4-5 times stronger than regular glass. If broken, it shatters into small, less dangerous pieces rather than sharp shards.
Laminated Glass
Contains a plastic interlayer that holds the glass together if broken. Offers higher security and better sound insulation than standard glass.
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