The height of the green fence around the former secondary school site on St Mary's is industry standard, the Council has said.
Diana Mompoloki, Senior Manager of Strategic Development, responded to some criticism in the community that the hoarding is too high and unattractive.
She told This is Scilly that the colour was chosen in consultation with the planning team to find the least offensive shade.
Diana said: "The school was demolished as it was unsafe, was constantly broken into and was making the site unattractive to anyone interested in providing affordable homes on the site as per the about to be published Local Plan. Therefore members took the decision to demolish the old school to de-risk the construction project to follow, on the advice of the Homes and Communities Agency, the Government body who funds affordable homes through Social Housing Providers.
"The site was very successfully demolished over the winter- this left a stockpile of large granite boulders, which we have earmarked for flood defence works and graded, crushed material which will be available for future projects."
She said of the green fencing : "The hoarding is designed to keep people off the site as the piles of stone and crushed material are not safe to allow access. The hoarding is industry standard in height and is designed to discourage people from climbing over.
"The green was chosen in consultation with the Planning Team to try to find the least offensive, least intrusive colour. The hoarding is not yet complete and will have viewing portals where the pavement runs along. As the site is developed in the future this will allow residents and visitors to see what is going on behind the hoarding."
She added: "We are working through the Island’s Housing Partnership to identify a delivery partner to ensure we deliver the housing the islands need. The draft local plan has identified the need for 120 affordable homes over the next 15 years.
"The Old School was demolished using funding from the Housing Reserve. If the site is not to be used for housing alternative funding would need to be sought.
"With the unmet demand for affordable housing and the difficulty in recruiting to roles such as carers in Park House due to problems finding housing, it would be a shame not to use our largest brownfield site."