When specific regions of London boroughs are referred to as ‘conservation areas in London‘ it means that the buildings in the area are protected in order to preserve the architectural history and culture. Your local authority has the power to designate as a conservation area, any area of special architectural or historic interest under Section 69 of the Planning Act 1990. This means the planning authority has extra powers to control works and demolitions of buildings to protect or improve the character or appearance of the area.
It's vital that you receive planning permission before commencing alterations to your property, as failing to do so can result in a hefty fine. The integrity of the design and materials used are important factors in the local authority’s decision in granting planning permission or permitted development for your loft conversion. Conservation areas are not intended to prohibit homeowners from making improvements to their London properties but any intended work must maintain the look and feel of the existing building and its area. Each local authority has its own policy for conservation areas but generally the basis of the policy is to prevent the loss of character of the Conservation Area.
The fact that your property is in a conservation area may have influenced the deciding to purchase your home greatly, so you'll be aware of the regulations surrounding it. However, if you are unsure, your local authority will have information regarding conservations in their borough. You can find more information about this on your council’s website. A list of the London boroughs can be found on the Direct Gov website.