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    Draught-Proof Your Windows: Thermal Secondary Glazing London

    Dramatically improve your home's energy efficiency with secondary glazing. Reduce heat loss, eliminate draughts, and lower your heating bills while preserving your original windows.

    The Hidden Cost of Inefficient Windows

    Windows can account for up to 40% of a home's heat loss. Single-glazed and older double-glazed windows are particularly inefficient, allowing precious warmth to escape and cold draughts to enter. This translates directly to higher energy bills and reduced comfort.

    Secondary glazing creates an insulating air gap between your existing window and the new internal panel. This trapped air acts as a thermal barrier, dramatically reducing heat transfer. The result is a warmer home that requires less heating to maintain comfortable temperatures.

    Unlike replacement windows, secondary glazing works with your existing frames, making it ideal for period properties, listed buildings, and conservation areas. You get the thermal benefits of modern glazing while preserving your property's original character.

    Our thermal insulation solutions can reduce heat loss by up to 65% and eliminate 100% of draughts. Combined with our noise reduction benefits, secondary glazing offers a comprehensive upgrade to your living environment.

    Thermal Benefits

    Transform your home's energy performance

    Up to 30% Energy Savings

    Significantly reduce heat loss through windows, lowering your heating bills.

    Improved U-Values

    Achieve U-values as low as 1.8 W/m²K, approaching double glazing performance.

    Condensation Prevention

    Eliminate condensation on original windows by creating a warmer inner surface.

    Reduced Carbon Footprint

    Lower energy consumption means reduced CO2 emissions from your home.

    Energy Savings

    Typical savings for a London home with secondary glazing

    Average annual heating saving£180-300
    Heat loss reductionUp to 65%
    Draught elimination100%
    Typical payback period3-5 years

    Understanding U-Values

    U-value measures thermal transmittance—lower is better

    Single glazing
    5.0 W/m²K
    Old double glazing
    2.8 W/m²K
    Single + Secondary glazing
    1.8 W/m²K
    Modern double glazing
    1.3 W/m²K

    Secondary glazing brings single-glazed windows close to modern double glazing performance

    How It Works

    Our thermal insulation process

    1

    Thermal Assessment

    We evaluate your current windows and identify heat loss areas.

    2

    Solution Design

    Custom secondary glazing designed to maximise thermal performance.

    3

    Expert Installation

    Precise fitting ensures optimal air gap and thermal efficiency.

    4

    Performance Verification

    We verify draught elimination and improved comfort.

    Thermal Glazing Pricing

    Thermal insulation secondary glazing typically costs £200-550 per square meter, with most homeowners seeing payback within 3-5 years through energy savings.

    From £400 per window

    Including survey, design, and installation

    • Free thermal assessment
    • Energy savings estimate
    • 10-year warranty
    • Condensation prevention
    Get Your Free Thermal Audit

    Cut Your Heating Bills by 30% This Winter

    Book a free thermal audit — we'll calculate your exact savings and payback period before you commit.

    Sources & References
    AI-verified

    Authoritative sources supporting the information in this article.

    1. British Standards Institution (2017). BS EN ISO 10077-1:2017 Thermal performance of windows, doors and shutters. Calculation of thermal transmittance. General. BSI Knowledge.Open source

      This is the primary British Standard for assessing the thermal performance of windows and doors, essential for calculating U-values in secondary glazing installations.

    2. Department for Levelling Up, Housing and Communities (2023). Approved Document L, Volume 1: Dwellings (2021 edition incorporating 2023 amendments). HM Government.Open source

      This regulation mandates the minimum energy efficiency standards for dwellings in England, specifically dictating the U-value requirements for replacement glazing and thermal improvements.

    3. Historic England (2016). Energy Efficiency and Historic Buildings: Secondary glazing for windows. Historic England Publishing.Open source

      Provides authoritative guidance on improving energy efficiency in historic buildings, specifically advocating for secondary glazing as a preferred method for thermal upgrades in listed London properties.

    4. BRE (Building Research Establishment) (2022). The Government’s Standard Assessment Procedure for Energy Rating of Dwellings (SAP 10.2). BRE Group.Open source

      Underpins the methodology for calculating energy performance certificates (EPCs) in the UK, highlighting the impact of secondary glazing on a building's overall thermal rating.

    5. Saint-Gobain Glass (2021). Acoustics and Thermal Comfort in Residential Glazing: The role of air cavities. Saint-Gobain Technical Library.Open source

      Technical white paper detailing the physics of acoustic decoupling and thermal barriers provided by secondary glazing systems in high-noise urban environments like London.