Aluminium vs Steel Windows: Which Is Better?

Last Updated on March 14, 2025

Choosing the right windows for your home is a significant investment. Whether you’re renovating a period property, upgrading your commercial building, or installing windows in a new build, the decision between aluminium vs steel windows can be complex.

Both materials offer distinct advantages, from durability and aesthetics to energy efficiency and cost-effectiveness.

In this in-depth guide, we’ll compare aluminium and steel windows across key factors, including insulation, security, maintenance, ventilation, and cost. By the end, you’ll have the information needed to decide which is best for your home.

Contents

1 Aluminium vs Steel Windows: A Quick Comparison
2 Aluminium vs Steel Windows: Which Is Better for Your Home?
3 Which Is Best for Your Home: Aluminium vs Steel Windows?
4 Comparing Aluminium Windows to Other Materials
5 Get a Free Quote for Aluminium vs Steel Windows

Aluminium vs Steel Windows: A Quick Comparison

Before diving into the details, here’s a quick comparison of aluminium and steel windows based on key features:

Feature	Aluminium Windows	Steel Windows
Aesthetic Appeal	Slim frames, modern look	Ultra-slim sightlines, industrial charm
Opening Mechanism	Casement, tilt-and-turn, sliding	Casement, pivot, fixed
Ventilation	Excellent due to multiple style options	Good, but often less operable styles
Energy Efficiency	High, with thermal breaks	Moderate, unless thermally broken
Security	Strong, multi-point locking systems	Superior, due to robust steel frames
Cost	£500 – £1,500 per window	£1,200 – £4,000 per window
Best Suited For	Modern homes, commercial properties	Industrial, heritage, luxury properties

Aluminium vs Steel Windows: Which Is Better for Your Home?

Both aluminium and steel windows have their unique advantages. Your choice will depend on your budget, the style of your property, and your priorities regarding durability, aesthetics, and energy efficiency.

Key Features of Aluminium Windows

Aluminium windows are lightweight, corrosion-resistant, budget-friendly, and available in various colours and styles.

Pros and Cons Aluminium Windows

Pros

Lightweight and easy to install
Highly energy-efficient with thermal breaks
More affordable than steel
Available in a variety of colours and finishes

Cons

Slightly thicker frames than steel
Not as strong as steel

Key Features of Steel Windows

Steel windows are incredibly strong, featuring ultra-slim frames, exceptional durability, and high security, but they come at a premium price.

Pros and Cons Steel Windows

Pros

Unmatched strength and security
Elegant, slim sightlines for maximum glass area
Extremely durable – lasts over 50 years

Cons

High initial cost
High initial cost

Which Property Types Are Best for Aluminium and Steel Windows?

Different property types will benefit from aluminium or steel windows depending on their architectural style, heritage considerations, and functional requirements. Choosing the right material ensures that your windows complement the character of your home while providing durability, energy efficiency, and security.

Best Properties for Aluminium Windows

Aluminium windows are versatile, lightweight, and offer a sleek, modern aesthetic. They are ideal for:

Modern and Contemporary Homes

Perfect for new builds and modern extensions.
Slim frames and a variety of colour options help create a minimalist aesthetic.
Complements homes with large glass panels, bi-folding doors, and open-plan living spaces.

Commercial Buildings

Cost-effective for office spaces, retail buildings, and apartment complexes.
Often used in high-rise buildings due to their lightweight and corrosion-resistant properties.
Large aluminium-framed windows allow for maximum light intake, enhancing work environments.

Mid-Century Homes (1950s-1970s)

Many homes from this era have large single-glazed windows that need updating.
Aluminium windows provide a modern upgrade while maintaining a retro look.

Edwardian and Victorian Homes (Renovation Projects)

Suitable for homeowners who want slim frames without the high cost of steel.

Best Properties for Steel Windows

Steel windows are known for their unmatched strength, ultra-slim sightlines, and ability to enhance period architecture. They are ideal for:

Heritage and Listed Buildings (Georgian, Victorian, Edwardian Homes)

Steel windows adhere to conservation guidelines while preserving the original character of period properties.
Their traditional steel look is often required in listed buildings or areas with strict planning regulations.
Often used in Victorian and Edwardian terraces, which originally featured slim steel window frames.

Industrial-Style Properties and Loft Apartments

The ultra-slim frames and grid-style designs create a factory-inspired, industrial aesthetic.
Ideal for warehouse conversions and loft-style apartments in urban areas.
Works well with Crittall-style steel doors and partitions.

Luxury Homes and High-End Developments

Adds a premium finish, often chosen for bespoke architecture.
Used in mansions and architect-designed properties for statement windows and oversized glass installations.
Preferred for exclusive renovations, where homeowners want the most elegant, long-lasting option.

Steel Windows vs Aluminium Window Styles

Both aluminium and steel windows are available in various styles to suit different property aesthetics:

Flush Windows

Sit flush with the frame, creating a clean and minimalist look.
Commonly used in modern and period properties, particularly in Victorian and Georgian homes.
Ideal for heritage renovations where a traditional aesthetic must be maintained.

Casement Windows

A versatile option that opens outward on a hinge.
Found in both traditional and contemporary homes.
Can be paired with glazing bars to mimic period-style windows or left frameless for a modern appearance.

Insulation & Energy Efficiency

Glazing Options

Glazing Type	Energy Efficiency Rating	Average Cost Cost per m²
Single Glazing	Low	£80 – £200
Double Glazing	High	£150 – £300
Triple Glazing	Excellent	£250 – £500
Low-E Coating	Superior heat retention	£200 – £450

Which Glazing Option Is Best?

Cheapest Option: Single glazing is the least expensive, but it provides poor insulation and is not recommended for energy efficiency.
Most Expensive Option: Triple glazing is the most costly but provides maximum insulation and noise reduction.
Most Energy-Efficient: Triple glazing with Low-E coating offers the highest thermal efficiency, reducing heat loss and lowering energy bills.
Best Balance of Cost & Efficiency: Double glazing provides a good compromise between price and insulation, making it the most popular option for homeowners.

For steel windows, double or triple glazing with thermal breaks is essential to prevent heat loss and condensation. Aluminium windows already come with built-in thermal breaks, making them a more energy-efficient choice.

Maintenance & Longevity

Factor	Aluminium Windows	Steel Windows
Cleaning	Low-maintenance	Requires anti-rust treatment
Wear and Tear	Resistant to corrosion	Prone to rust if not maintained
Longevity	30-45 years	50+ years

Which Window Material Requires More Maintenance?

Aluminium Windows require minimal maintenance due to their corrosion resistance.
Steel Windows need regular anti-rust treatments, particularly in coastal areas where exposure to moisture and salt can accelerate corrosion.

Which Window Material Lasts Longer?

Steel windows have an incredibly long lifespan of 50+ years, making them a lifetime investment.
Aluminium windows can last between 30-45 years, which is still a long-term solution but slightly shorter than steel.

Which Is the Best Option for Longevity & Low Maintenance?

For longevity, steel is the best choice, provided it is properly maintained.
For low maintenance, aluminium is the winner, as it requires no rust prevention treatments.

Costs & Installation

The cost of new windows depends on several factors, including the window size, material, type of glazing, and complexity of the installation. Below, we’ll compare the average prices of aluminium vs steel windows:

Pricing Table for Aluminium vs Steel Windows

Window Type	Aluminium Cost	Steel Cost
Casement Window	£500 – £1,200	£1,500 – £3,500
Flush Window	£700 – £1,500	£2,000 – £4,000
Sliding Window	£800 – £1,800	£2,500 – £4,500

Which is cheaper?

The cost of aluminium windows is significantly cheaper than steel.
Steel windows are more expensive due to material strength and craftsmanship.

Installation Requirements & Timeframe

Aluminium windows: Quick to install (1-2 days per window).
Steel windows: Requires specialist installation and can take longer (2-4 days per window).

Which Is Best for Your Home: Aluminium vs Steel Windows?

Ultimately, aluminium is the best choice for affordability, energy efficiency, and versatility. However, steel is the premium option for those wanting ultra-slim sightlines and durability.

If you’re on a budget, aluminium windows will provide excellent long-term performance. But if you own a heritage home or industrial-style property, steel windows will elevate your property’s aesthetics.

Comparing Aluminium Windows to Other Materials

If you’re still weighing your options, it’s helpful to compare aluminium windows with other popular materials. Check out these in-depth comparisons to make the best choice for your home:

Aluminium windows vs uPVC windows – While aluminium and UPVC both offer unique benefits, they differ in terms of durability, thermal efficiency, and maintenance needs.

Aluclad vs aluminium windows – Aluclad windows offer a combination of materials, and understanding their difference from pure aluminium can help clarify which is the better option for your home.

Aluminium vs wood windows – The contrast between aluminium and wood can be striking, particularly in how each material handles insulation, longevity, and visual appeal.

Get a Free Quote for Aluminium vs Steel Windows

If you’re looking to install high-quality aluminium or steel windows, our team can help. Whether you need windows for a residential property, commercial building, or a listed property, we provide expert installation and competitive pricing.

Request a free quote today and we will provide you with the best window solutions for your home.

James Elston

Boiler Expert

James Elston is the top boiler replacement and heating expert at Eco Happy. He has over 20 years of experience in the industry, focusing on Gas Safe boiler installations and offering home-heating and energy-saving solutions to homeowners across the UK. From sourcing the most energy-efficient combi boiler to providing specialist heating advice, James ensures that Eco Happy maintains the highest standards and best customer service.

Aluminium vs Steel Windows: A Quick Comparison

Aluminium vs Steel Windows: Which Is Better for Your Home?