NEW YORK (CNNMoney.com) - Not only do homeowners want bigger kitchens, they want more of them.

That's the finding of the latest edition of the Quarterly Home Design Survey from the American Institute of Architects. The survey concentrated on trends in kitchen and bath design, which it calls "the areas in homes that get the most design attention."

The report quoted AIA Chief Economist Kermit Baker saying, "Both the square feet devoted to kitchens and the number of separate cooking facilities throughout the home are increasing, including the additions of outdoor kitchens in many areas of the country."

Kitchens have become the focal point of many American homes, according to the report, and they feature more space, more upscale appliances, and are better integrated with other family areas than even before.

As for specific features, 56 percent of architectural firms reported that clients wanted more pantry space, the No. 1 up-trend in kitchen design.

Baker also said that in regard to specific kitchen trends, granite countertops, natural wood cabinets, and drinking water filtration systems are all still going strong.

High-end appliances are much in demand with 55 percent of firms reporting increased popularity.

On the down side were solid surfacing countertops -- 37 percent of architects say they are less popular and only 13 percent said more.

As for bathrooms, they too are still growing in size, number – and luxury.

"Upscale products and features are going into bathroom design as well, noted by heated floors and towel racks, and even fireplaces becoming more common in homes," said Baker.

Multi-head showers are showing the most momentum in bath design with 63 percent of firms reporting an increase in requests for this feature. On the outs are whirlpool baths with 31 percent of firms giving them thumbs down.

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