Business Details
Your Trusted Window and Door Specialists in Derby
Capital Windows Derby is a trusted provider of premium windows, doors, and home improvement solutions serving Derby, Derbyshire, and surrounding areas. With over 100 years of combined experience, our team specialises in energy-efficient double-glazed units, Veka Storm casement windows, GRP doors, Guardian Warm Roof systems, and bespoke home extensions. Accredited by FENSA, Gas Safe, and NIC EIC, we prioritise quality craftsmanship, security compliance, and customer satisfaction. Our services include SupaLite conservatory roofs, bi-folding doors, and project-managed renovations tailored to modern living requirements while maintaining heritage standards for listed properties. 
Services
Double-glazed windows
Security doors
Conservatory roofs
Home extensions
Bi-folding doors
Highlights and features
- Over 100 years of combined experience in home improvements
- FENSA, Gas Safe, and NIC EIC accredited professionals
- Energy-efficient double-glazed units reducing bills by up to 50%
- Project-managed installations from concept to completion
- Security-focused doors with 10-year guarantees and 24/7 support
Associations and certifications
- FENSA
- Gas Safe
- NIC EIC
Services
Double-glazed windows
Our double-glazed units significantly reduce energy bills by up to 50% through advanced thermal insulation. Manufactured with Veka Storm profiles and conservation-approved plastics, these windows combine durability with aesthetic appeal. Available in multiple styles to complement both modern and traditional properties.
Security doors
GRP doors with reinforced insulation and 3-star British Standard locks provide maximum security. Featuring unbreakable locking cylinders with manufacturer-backed guarantees, our doors offer 24/7 protection while maintaining thermal efficiency. Available in various colours and glass options for customised solutions.
Conservatory roofs
Guardian Warm Roof systems transform conservatories into year-round living spaces. These lightweight insulated roofs replace glass or polycarbonate structures, maintaining comfortable temperatures while adding property value. Includes LED lighting and vaulted plaster ceilings for an extension-like finish.
Home extensions
Full-service home extensions from design to completion, including loft conversions and orangery installations. Our project-managed solutions adhere to building regulations with NIC EIC-certified electricians and Gas Safe engineers. Designed to enhance living space while preserving architectural integrity.
Bi-folding doors
Origin OB-49 bi-folding doors combine slimline aesthetics with 20-year durability. Featuring 49mm sightlines, 8-point locking systems, and U-values of 1.2 for optimal thermal performance. Stainless steel trims and 1200mm panel widths create seamless indoor-outdoor transitions with minimal maintenance requirements.
Questions
Do you offer energy-efficient window solutions?
Yes, our double-glazed units reduce energy bills by up to 50% through advanced thermal insulation technology.
Are your doors security-certified?
All doors meet 3-star British Standard Kitemark requirements with unbreakable locking systems guaranteed by manufacturers.
Can you convert conservatory roofs?
We install Guardian Warm Roof systems that transform glass roofs into insulated living spaces with 10-year guarantees.
Do you handle full home extensions?
Yes, we provide complete project-managed extensions including design, planning, and building regulation compliance.
What areas do you serve?
We operate within a 25-mile radius of Derby, covering Derbyshire, Nottingham, and Burton regions.
Are your installers accredited?
Our team holds FENSA, Gas Safe, and NIC EIC certifications ensuring industry-standard compliance for all installations.
