Residents in Kingsdown say the view from their homes will be destroyed and the surrounding area "degraded" if Bristol University's multimillion-pound building plans get the go ahead.

In a row which has been brewing since 2005, residents are set to oppose plans for a £35-million complex to house the university's schools of biological sciences and mathematics.

The proposed facilities will be built on the site of the old children's hospital at the top of St Michael's Hill but residents say the size of the buildings, which reach up to six storeys, will block the view of the Royal Fort Tower and damage the character of the upper part of the St Michael's Hill conservation area.

John Frenkel, 66, secretary of Kingsdown conservation group, will speak at the council planning meeting on Wednesday when a decision over the scheme will be made.

Mr Frenkel, who lives in Somerset Street, Kingsdown, said: "Firstly, we want to highlight the community cohesion over this issue. I'm speaking for the Kingsdown conservation group, the Christmas Steps Arts Quarter, Redland and Cotham Amenity Society and Bristol Civic Society and we have the backing of everyone involved.

"Secondly, we're very disappointed to have to oppose the university. Many of us have had to deal with divided loyalties over this. We don't want to have to fight but we feel the building is too big and will put an end to the character of the area.

"We just want the university to follow its master plan and build based on the original design, which had four floors. No one will really give us a definitive answer why the university have ignored this."

Michael McKee, an architect who lives on Robin Hood Lane, Kingsdown, said: "The outcome of public consultation resulted in a proposal for a four-storey building fronting St Michael's Hill, which was accepted by all parties involved. Although the scale of the surrounding buildings is limited to three storeys it was felt that with appropriate detailing a four-storey building would be acceptable.

"However, the current proposal now in front of the committee is over six storeys in height which makes constructive criticism difficult to achieve.

"Recent alterations to the scheme seem to have been based solely on a futile and impossible attempt to have the proposal regarded within the initial design parameters set for the site."

The biological science department is currently based in a large Victorian townhouse in Woodland Avenue, but the science faculty says it is too small and unsuitable for research and teaching in the 21st century.

A university spokesman said: "The proposed developments will not only help the university pursue key areas of science at the highest international levels, but will also bring real economic and environmental benefits to Bristol. We have consulted widely over the past 18 months and have adjusted our plans substantially in response to the views of local residents and others. We believe the proposals are in line with the approved master plan and that the development will be seen by most people as a major improvement to this part of Bristol."

The council's development control committee is meeting on Wednesday to discuss the plans.