The luxurious update of the Downing Street abode was reportedly inspired by a desire to get rid of the "John Lewis furniture nightmare" left behind by Mr Johnson's predecessor, Theresa May.
Some reports suggest the work cost an eyewatering £200,000, with the couple enlisting the services of a leading interior designer to consult on the project.
Earlier on Wednesday, the Electoral Commission launched an investigation into how the new look was funded, amid claims Mr Johnson borrowed money from Tory Party HQ or a wealthy Conservative donor.
The prime minister continues to insist he covered the cost of the work himself, although he and his office have repeatedly dodged questions on whether the invoices were first paid by a third party.
On Twitter, John Lewis said: “Time for an interiors refresh? We pride our Home Design Service on having something for *almost* everyone.”
Labour leader Keir Starmer's spokesman said “unlike the prime minister he doesn't turn his nose up to John Lewis thinking it's too downmarket” and "wouldn't spend £840 per roll on wallpaper".
The Electoral Commission said there were "reasonable grounds to suspect that an offence or offences may have occurred" during the financing of the revamp of the prime minister's flat.
The taxpayer funds a £30,000 annual allowance for renovations at 11 Downing Street, but the redecoration - reportedly involving the company Soane, co-founded by top designer Lulu Lytle - has stretched beyond that.
A leaked email suggested Tory peer Lord Brownlow was making a £58,000 donation to the Conservatives "to cover the payments the party has already made on behalf of the soon-to-be-formed 'Downing Street Trust"'.
Mr Johnson's former adviser Dominic Cummings said he told Mr Johnson "his plans to have donors secretly pay for the renovation were unethical, foolish, possibly illegal".
Additional reporting by Press Association
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies