A new study published by automotive industry website just-auto.com suggests that the market for integrated vehicle door modules supplied to vehicle manufacturers by specialist suppliers is set to grow rapidly as vehicle makers increasingly turn to outsourcing for cost savings.

The just-auto.com report forecasts that the fitment rate of door modules to light vehicles in Western Europe will increase from 25% in 2006 to 44% by 2012. In North America and Japan the fitment rates rise in the same period from 14% and 5% to 27% and 8%, respectively.

The report says that the benefits to the carmaker from outsourcing door modules centre on cost and weight savings. Some suppliers believe that a move to door modules could save the vehicle maker up to $20 per car (around 10% of door set cost), although the actual savings will vary according to the processes, materials and the level of integration already in place. 

Door module producer Faurecia estimates that when a carmaker moves from conventional door assembly to door modules, the time to assemble the door falls from about 25 minutes to just five minutes because only one element has to be assembled as opposed to ten. 

"We design and produce door panels, door modules and complete doors for carmakers worldwide," said Heinz Josef Rüsche, sales and marketing director of Faurecia's door business. 

"Although demand for complete doors is more focused on assembly than development, the involvement of suppliers in the door design is more and more important. Above all, carmakers are relentless in their pursuit to reduce cost and weight. In respect of door modules, we are able to use our skills in plastic composite technology to meet carmakers' demands," he said.

ArvinMeritor's Light Vehicle Systems Door Systems division has created a new and highly integrated door module which replaces the traditional steel carrier frame with a composite plastic structure that saves about 25% in weight. The HIP (highly integrated plastic) module is the fourth generation of a design that was begun in the 1990s.

Thanks to plastics moulding technology, the company has designed in fixtures and attachments for the various components such as the latching system, window motor and audio speakers that greatly reduce assembly complexity. Once vehicle manufacturers begin buying the technology in around three years' time, the company estimates they will be able to achieve cost savings per door of around 25-30%. 

"The HIP is a design and development programme aimed at addressing two main business drivers: cost and weight," said Mark Lawrie, Chief Engineer, Window Regulators & Modules, ArvinMeritor.

The full just-auto.com report, 'Global market review of door modules 2006 edition - forecasts to 2012', is available for purchase at a price of £398 by following this link: /store/products_detail.asp?art=39382&lk=ss.