Full indoor heating will allow the space, which opened on Friday (23 September), to be used for events during autumn and winter for the first time.
The structure stands at three metres tall and runs the full length of the courtyard. It can hold 120 guests standing or 80 seated.
It will be open at Dartmouth House, part of the Lime Venue Portfolio, until 22 December and is decorated with oversized lanterns and fairy lights.
Dartmouth House general manager Richard Fisher said: "Our courtyard is one of the rarest features available in a London venue and is especially popular for receptions during the summer months. We are delighted that its use will now transcend through to winter and the festive party season."
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