Secondary Glazing in Mayfair, Belgravia & St James's

Covering nearly all of W1K and W1J, this is one of London's largest conservation areas. The Grosvenor Estate manages much of the freehold, and their surveyors require detailed specifications for any window alteration. Our secondary glazing has been approved on properties across Berkeley Square, Mount Street, and Carlos Place. We supply the technical drawings and heritage impact statements the Estate requires. The Grade II listed Georgian townhouses around Grosvenor Square (c.1725-1731) feature some of Mayfair's most significant original sash windows with hand-blown Crown glass.

Key streets: Berkeley Square, Grosvenor Square, Mount Street, Carlos Place, Bruton Street, Albemarle Street, Dover Street, Upper Grosvenor Street, Brook Street

Developed by Thomas Cubitt from the 1820s for the Grosvenor family, Belgravia is the finest surviving example of Regency-era urban planning in Europe. The magnificent stucco-fronted terraces around Belgrave Square, designed by George Basevi, feature 12-over-12 sash windows with original handmade glass. Our secondary glazing sits 150mm behind these priceless originals, completely invisible from the square's garden. We hold Grosvenor Estate approved contractor status and have completed installations in 30+ Belgrave Square properties.

Key streets: Belgrave Square, Eaton Square, Chester Square, Wilton Crescent, Wilton Place, Halkin Street, Grosvenor Crescent, Eaton Place

St James's is managed by the Crown Estate and contains some of London's finest 17th and 18th-century architecture, including properties on St James's Square (designed by Henry Jermyn, 1st Earl of St Albans, from 1660). The gentlemen's clubs along Pall Mall and the grand terraces of Carlton House Terrace (John Nash, 1827-1833) present unique glazing challenges due to their monumental scale and Grade I listed status. We work directly with the Crown Estate's heritage team to ensure every installation is invisible and fully reversible.

Key streets: St James's Square, Pall Mall, Jermyn Street, Carlton House Terrace, King Street, Duke Street, Bury Street, Ryder Street

The grand 19th-century mansions and mansion blocks along Park Lane face relentless dual-carriageway traffic. Properties like those on Stanhope Gate and Tilney Street experience sustained noise levels of 75+ dB. We've installed triple-layer acoustic secondary glazing in several Park Lane penthouses, achieving internal levels below 30 dB -- quieter than a library. Shepherd Market, Mayfair's intimate village quarter dating from Edward Shepherd's 1735 development, requires bespoke measurement as no two windows are alike.

Key streets: Park Lane, Stanhope Gate, Tilney Street, Aldford Street, South Street, Shepherd Market, Curzon Street, Half Moon Street