BEIJING, Nov. 20 (Xinhua) -- Beijing is to double its investment in the renovation of its ancient downtown buildings next year with a budget between 1.5 billion yuan (220.6 million U.S. dollars) and 2 billion yuan.

    About 20,000 families in the districts of Dongcheng, Xicheng, Chongwen and Xuanwu will benefit from the project, which will be focused on aging homes in dangerous condition, vice mayor Chen Gang said on Wednesday.

    Siheyuan, or courtyard homes, are common in Beijing's hutong, or alleyways.

    Their residents complain about leaking roofs in summer, fire hazards and dangerous electricity cables. They must also share water taps, electricity and toilets with neighbors, which sometimes lead to quarrels.

    "Issues concerning people's living standards should be resolved quickly. We should begin renovations in the early spring," Chen said.

    "The goal is that no more shabby and dangerous homes should be found in downtown Beijing within two or three years," he said.

    The city authorities would ban the involvement of real estate developers in the renovation project to avoid massive demolitions and reconstruction and protect residents' rights, Chen said.

    The government would bear the renovation costs for public buildings and half of the costs for private buildings, he added.

    Beijing started a huge renovation project in October last year with an investment of 1 billion yuan, the largest of its kind since 1949 when the People's Republic of China was founded. Some 10,576 families in 1,954 courtyards in 44 hutong have benefited from the project, which has enabled each family to have its own toilet and tap water.

    The government said it had taken care to avoid damaging the traditional look of hutong to preserve their historical and cultural significance.

    Beijing still had about 2 million square meters of old homes in downtown areas, said Sui Zhenjiang, head of the Municipal Committee of Construction.

    "We're assessing the specific number of such houses. The renovation is not aimed at improving their outlook, but at improving the living conditions for the residents," he said.

    Under the plan, a third of the 20,000 families will move out of downtown districts next year to ease the population pressure in the heart of the city.

    "The government will not force residents to move out. The evacuation is completely based on the residents' own wishes, and they need to submit applications themselves," Sui said.

    The government had prepared favorable locations in four outer districts for residents who were willing to move, he said.