Beyonce is reportedly house-hunting without the hubby.

The 32-year-old singer has fuelled rumours she and her husband are on the rocks after she was spotted secretly viewing a $21.5 million Chelsea penthouse in Manhattan last month without her Jay Z knowing.

A source told the New York Post's Page Six: "She was very quiet, as if she was looking on the sly." Not sure what they expected her to do, suddenly break out into an impromptu performance of Bootylicious in the bathroom, or something.

The couple - who have two-year-old daughter Blue Ivy - currently reside in a plush mansion in Tribeca, New York, and the insider believes it's highly unlikely the 44-year-old rapper would be downsizing to the 4,045-square-foot apartment in Chelsea.

The source added: "I can say with certainty that Jay is not downsizing."

News that Beyonce, who married Jay in 2008, is looking for her own place follows recent reports that the power couple's marriage is "crumbling."

A friend of the couple said previously: "Knowing them as I do, obviously there's a little something to certain reports. When your man or your woman isn't getting it done for you, and I'm talking emotionally, not necessarily sexually... they keep things quiet."

The duo are reportedly receiving marriage therapy via Skype while on their On The Run tour but their sessions aren't proving a success as Jay allegedly prefers to spend his time on his mobile.

The source added: "His phone's constantly ringing. Jay trying to make [business] deal after deal."

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