The Alp System, an easy and fast method of installing of pre-insulated air-conditioning ducts, has been successfully used on the office tower at the Emirates Towers project in Dubai.

The air ducts, which have been under development since 1980, use special aluminium/polyurethane sandwich panels that allow fast and easy construction, says its Italian manufacturer. The system has passed the most severe technical tests and attained first-class approvals, says sales manager Marco Pescali.

Because of their technical characteristics, the air ducts are widely used in air heating/conditioning installations in civil, commercial and industrial buildings, such as offices, shopping centres, hotels, airports, hospitals and clean rooms, he adds.

At the Emirates Tower project, Alp's trapezoidal shape rising ducts have been used.

"It was the flexibility and the innovation of its air ducts that enabled Alp to secure such a major contract," says Pescali. "The rising ducts had to be produced in a number of unusual ways in the office tower. The ducts were designed to be fitted in trapezoidal-shaped hollow columns. These columns were completed closed by walls and the only access to them was via a hole in the floor.

"This meant that the only way to install the ducts was to lower them down into the columns from the designated floor. Only three floors were designated for access for installation and the tallest column was 99 m deep.

"The air ducts were fabricated directly at the designated floor and lowered into the columns, saving a lot of time and making the installation quick and easy.

"The ducts used for the project were designed to have large sections. This would normally cause quite a problem as galvanised steel ducts are very heavy, leading to problems with installation and supporting.

"The unique way that Alp's air ducts are produced meant this did not occur. This was a major reason for the company gaining such an envied contract."

The ducts have also been installed at the Ajman City Centre, Dubai TV, Sharjah Zoo and Al Bustan Residence.

A strong selling point of the air ducts is their simple construction, says Pescali. "The air ducts are constructed of panels that are cut, glued and then assembled to form any shape or dimension. This easy construction does not take anything away from the performance, as the air ducts have sound mechanical properties and can be used in a wide range of operating conditions under air pressure up to 2,000 pascal and air temperature ranging from minus 35 to 110 deg C and air speeds of up to 35 m/sec," he says.

The Alp System presents many advantages compared to the traditional air ducts produced from galvanised steel insulated with glass wool, claims Pescali.

He elaborates: "For example, as the air ducts are pre-insulated, no additional work is required to insulate the ducts or to insulate the joints after the installation. They offer better insulation and are lightweight, being one-tenth the weight of steel ducts by comparison and hence requiring fewer supports.

"Other benefits include better sealing, very low air leakage, easy and fast installation, very good quality of air as there is no rust inside the duct and durability.

"In addition, the price of the Alp System ducts is very competitive."