For the last 15 years, The Portman Estate has been regenerating its large portfolio, bringing its buildings up to the highest of 21st century standards whilst ensuring it retains the beautiful historic features of the buildings.
The Gloucester Place development is the most recent of The Portman Estate's refurbishment projects, nestled in its prime area of London's West End, spanning across 110 acres of Marylebone. The majority of the buildings along Gloucester Place were built between 1787 and 1792, the terraces were added at a later date and completed in 1820.
Over the next 7 years, The Portman Estate's directly managed portfolio will be advanced further by 13 new and refurbished retail units, over 180,000 sq. ft. of new and refurbished office space and 4 new hotels.
The townhouses were typical of the Georgian period featuring ornate cornices and skirtings inside an uniformed exterior brickwork complete with balconies and cast iron railings. The six townhouses underwent an extensive renovation in order to convert the properties into one large hotel. A key issue identified during the transformation was the original windows, which were draughty, thermally inefficient and allowed noise ingress - not a comfortable environment for guests of a hotel.
Due to the Listed status of the buildings, the existing windows could not be replaced, so an alternative solution had to be found. Owing to a good working relationship spanning a number of years, The Portman Estate sought advice from Selectaglaze on the best secondary glazing application for their requirements.
Selectaglaze installed in excess of 80 secondary glazed units. The Series 90 was used on the larger windows which were up to 3m high and used up to 10.8mm thick glass. It is a heavy duty vertical sliding unit with specialist balances which allow large and weighty panels to operate with ease. When thicker glass is used, coupled with a gap between the primary and secondary glazing of at least 100mm; they work together to stop the glass from resonating and allowing sound through. This dramatically reduces the outside noise entering into the room. Using an acoustic laminated glass helps to absorb the sound even more, resulting in noise reductions of at least 46dB.
All the secondary glazed units were fitted with low-E glass, which provides U-values of around 1.8, to help reduce heat loss throughout the building. The inclusion of bespoke fixings to ensure the tightest fit and high performance seals minimises air leakage and draughts, making the environment more comfortable and thermally efficient. Selectaglaze secondary glazing units match existing sight lines wherever possible to make them virtually unnoticeable and as a fully reversible adaptation; they are accepted by most heritage bodies.
Selectaglaze has fifty years' experience working on all manner of buildings from Listed museums to new build hotels. Selectaglaze works closely with clients to ensure their requirements are met to make buildings warmer, quieter and safer.