After closing for trade on Sunday 4 August, the pub will not reopen again until 19 November.
Current staff will be redeployed to other sites in the region, before returning for the opening over three months later.
A further 15 full and part-time roles will be created once the pub reopens, a spokesman for the pubco has said.
The pub, on South Street in the centre of Romford, opened as a JDW site in May 1994 and will receive a new roof garden as part of the works.
Access to the roof garden
New furniture, lighting and fixed seating will also be installed, as well as new access to the roof garden.
The interior will be overhauled and completely redecorated, with a new colour scheme and carpets, as well as upgraded furniture throughout.
Both the ladies’ and gentlemen’s toilets will also be fully refurbished.
New staff facilities will also be added, as well as an upgraded kitchen and bar equipment.
The site’s manager Daniel Griffin said: “Wetherspoon is spending £1.1m on the pub, providing further substantial investment into the area, as well as creating new jobs for local people.”
Griffin continued: “Myself and my team will look forward to welcoming customers back into the Moon & Stars in November, and we are confident that they will be impressed by the refurbishment and new roof garden.”
The news follows JDW chair Tim Martin’s decision to make no further openings over the current financial year in the company’s pre-closing statement announced on 10 July.
In it, a like-for-like sales increase of 6.9% and a total sales rise of 6.6% were revealed for the 10 weeks to 7 July 2019.
Year-to-date sales were also up by 7.4%, accounts showed, which also revealed the company had spent £71m buying the freeholds of pubs where it was previously a tenant.
As a result, net debt for the end of the financial year was expected to be at around £745m.