AluK vs Crystal Windows

Average Price

£850

AluK

£560

Crystal Windows

U-Value

1.1 W/m²K

AluK

1.3 W/m²K

Crystal Windows

Warranty

20.0 years

AluK

10.0 years

Crystal Windows

Customer Rating

4.5/5

AluK

4.1/5

Crystal Windows

AluK vs Crystal Windows: Summary

When comparing AluK and Crystal Windows windows, several key differences emerge. AluK, established in 1994, offers windows with an average U-Value of 1.1 W/m²K at an average price of £850. Meanwhile, Crystal Windows windows average 1.3 W/m²K U-Value at £560.

AluK windows come with an average warranty of 20.0 years, compared to Crystal Windows's 10.0 years. Customer satisfaction ratings show AluK leading with 4.5/5, while reliability scores give AluK a slight edge.

Both manufacturers offer smart glazing technology and produce windows suitable for different property types. Both are based in United Kingdom.

Detailed Comparison

AluK
Crystal Windows
Average Price
£850
£560
U-Value
1.1 W/m²K
1.3 W/m²K
Energy Rating
A+
A
Average Warranty
20.0 years
10.0 years
Reliability Score
4.6/5
4.2/5
Customer Satisfaction
4.5/5
4.1/5
UK Market Share
9.0%
3.1%
Established
1994
1992
Country of Origin
United Kingdom
United Kingdom
Smart Glazing Technology
High Efficiency (U-Value ≤ 1.2)
Extended Warranty Options

Who Should Choose AluK

  • Those prioritizing energy efficiency with better U-Value
  • Tech-savvy homeowners wanting smart glazing features
  • Those who prefer to support UK manufacturing
  • Homeowners looking for classic casement window designs

Who Should Choose Crystal Windows

  • Those looking for windows with strong performance

Scenario Fit: Which Brand Fits Your Situation?

Best for budget-first upgrades

Crystal Windows is generally the lower upfront-cost option in this comparison.

  • • Better for large multi-window projects with tighter budget caps
  • • Useful when payback speed matters more than premium extras
  • • Pair with installer quote comparisons to lock value

Best for long-term ownership

AluK currently leads on warranty depth in this matchup.

  • • Better fit if you plan to stay in the home 10+ years
  • • Prioritises lower maintenance surprises over time
  • • Stronger risk control for exposed or high-traffic elevations
Decision LensLikely Better ChoiceWhy
Upfront budgetCrystal WindowsLower average price in this pair.
Energy performanceAluKLower U-Value typically means stronger heat retention.
Maintenance risk framingAluKLonger average warranty can reduce long-tail ownership risk.
User-rated confidenceAluKHigher customer satisfaction score in current data.

Popular Window Models

AluK Popular Models

ModelTypeMaterialRatingU-ValuePrice
Optio 58BDCasementAluminumA+1.1 W/m²K£700
SL52 SlidingSlidingAluminumA1.2 W/m²K£1000

Crystal Windows Popular Models

ModelTypeMaterialRatingU-ValuePrice
RapidFit EliteCasementuPVCA+0.8 W/m²K£550
AcousticProTilt & TurnuPVCA0.9 W/m²K£750

Approved Installers

AluK Installers

AluK Approved Fabricators

4.6

Approved Fabricators

Crystal Windows Installers

No installer data available

Energy Efficiency & Cost Savings

More energy-efficient windows can significantly reduce your heating bills. Based on average UK energy prices and a typical 3-bedroom house:

AluK

Average U-Value

1.1 W/m²K

Lower is better for heat retention

Energy Rating

A+

Estimated Annual Energy Savings

£327

Compared to older single-glazed windows (typical U-Value 5.8)

Crystal Windows

Average U-Value

1.3 W/m²K

Lower is better for heat retention

Energy Rating

A

Estimated Annual Energy Savings

£300

Compared to older single-glazed windows (typical U-Value 5.8)

Frequently Asked Questions

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