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Quick Product Snapshot
Key Information at a Glance
Opening Style
Outward side-guided opening
Frame Material
Timber or aluminium-clad timber, depending on chosen Rationel range
Best Suited For
Upper-floor windows, bedrooms, living spaces and homes needing practical access
Glazing Options
Double or triple glazing with acoustic, solar-control, safety, security and privacy glass options
Energy Performance
Designed for strong insulation and acoustic comfort, with triple-glazed options available across suitable ranges
Security
Security hardware and laminated glass options available, with enhanced security specifications possible
Warranty
Rationel timber/aluminium windows are typically covered by a 10-year warranty; timber windows by 5 years, subject to product range and terms
Design & Options
Rationel windows are made bespoke, so the design can be built around the property rather than limited to a standard size or finish. The main choices are whether to use all-timber or aluminium-clad timber, which opening function suits the room, and which glass specification is needed for comfort, privacy, security and acoustic control.
✓ Choose timber for a natural finish, or aluminium-clad timber for a lower-maintenance exterior.
✓ More than 200 colour choices are available, with different internal and external colours possible on suitable ranges.
✓ Glazing options include SOUND, SOLAR, OBSCURE, safety, security, patterned and coloured glass.
✓ Double or triple glazing can be selected depending on thermal, acoustic and project requirements.
✓ Opening functions can be matched across the home, including side-hung, top-guided, side-guided, tilt-turn, fixed and shaped units.
Why choose RATIONEL Side Guided Windows
Rationel side guided windows are ideal when you want the style and quality of timber but need a more practical opening function. They provide controlled ventilation and useful access, making them a good option for upper floors and rooms where ease of use matters as much as appearance.
Key Features
Practical guided opening
for easier operation
Premium timber construction
for a premium feel
Low-maintenance clad option
for less exterior upkeep
Useful for upper floors
where access matters
Performance & Comfort
Rationel side guided windows combine thoughtful opening design with strong thermal, acoustic and security options. They are built to feel solid, look refined and perform well in real homes, especially where upper-floor usability is important.
Energy Efficient
Triple-glazed ranges achieve U-values from 0.78 W/m²K.
Enhanced Security
Security hardware meets Secured by Design requirements.
Weather Resistance
Low-maintenance alu-clad option with 40-year life expectancy.
Acoustic Comfort
Triple glazing gives up to 42–43 dB Rw sound reduction.
Are RATIONEL side guided windows right for your property?
Side guided windows are useful when a project needs a refined timber window with a more practical opening function. They work well on upper floors and in rooms where controlled ventilation and access need to be considered alongside appearance. This style is a good match for renovation projects where the finish needs to feel high quality, but the window still has to be easy to use and maintain.
HOME RENOVATIONS
NEW BUILDS
EXTENSIONS
CONVERSIONS
