The firm hired designer David Bowling who introduced stained glass coloured windows, curves and angles reminiscent of a modern art museum. The new extension is set at an eight degree from the old building to avoid boring straight lines.
Special projects manager Gordon Mcrae said it looked fantastic and stemmed from Gripples ethos of creating impressive workplaces.
The firm makes a clever wire joining device used in fencing and to suspend everything from lights to bridges.
Mr Mcrae said: We are really proud of what we have achieved with this building. We started wild and wacky and tried to rein it in.
Most people start with an architect, we started with a designer to create this amazing building.
This move gives us more capacity and makes us more efficient. Its also one of the greenest manufacturing sites you will find.
Gripple Riverside has 400 solar panels on the roof and is heated using water from the River Don.
Some 15 jobs have been created, with more forecast this year.
Gripple also has a headquarters on Savile Street East and sister company Loadhog on Hawk Street, both in Attercliffe, as well as sites overseas.
The group employs 500, creates 40 jobs-a-year, turns over £55m annually and made £5m profit in 2016.
It makes 50m Gripples a year and sells them in 80 countries. But 70 per cent of its supply chain is in South Yorkshire.
Mr Mcrae also said they spent £250,000-a-year on patents.
He added: We see copies quite frequently from around the world, but they dont perform. In the two instances we went to court, the judge found in our favour.
The Gripple was invented by former wire salesman Hugh Facey who established the company in 1991, he is still boss today.
The firm is employee-owned and famous for playing fair.
The Master Cutler will officially open the new factory in June.