England has a robust, national strategy for the conservation and adaptive re-use of the existing built environment. The National Planning Policy Framework (NPPF) is intended to contribute to the achievement of sustainable development and to protect the historic environment. The NPPF has 12 core planning principles, one of which is that ‘planning should conserve heritage assets in a manner appropriate to their significance’ because they contribute to the overall quality of life and should be enjoyed by both current and future generations.

Conservation areas are defined under The Planning (Listed Buildings and Conservation Areas) Act 1990 as “areas of special architectural or historic interest, the character or appearance of which it is desirable to preserve or enhance.” The intent is not to prevent change, but to manage it in such a way that the architectural and historic character which led to the designation of the Area in the first place is not adversely affected. Designation of a Conservation Area constrains the type and extent of changes which owners can make to their property by adding an additoinal set of planning controls to those already in effect. After an Area is designated, local Councils can change the types of alterations that need permission by making Article 4 Directions.

Any new development in a Conservation Area that requires planning permission will only be approved if the Council is convinced that it will reinforce the 'special character' of the Area. Permission from the local Council will usually be required in order to make alterations to a building such as changing the cladding, inserting windows, installing satellite dishes and solar panels, adding conservatories or other extensions, laying paving, or building walls. And of course, demolition of all or part of a building will almost certainly require planning permission.

The trees in Conservation Areas are also subject to regulations. Anyone wishing to prune or cut down a tree must notify Council at least 6 weeks in advance. This gives Council time to assess whether the tree makes a contribution to the character of the conservation area sufficiently important to warrant the making of a Tree Preservation Order.

There are ten Conservation Areas in Harlow, five of them in the immediate vicinity of the Memorial University campus: Harlowbury, Old Harlow, Churchgate Street, Harlow Garden Village and Mark Hall North. The others are Harlow Mill and Old Road North, Netteswellbury, Town Park and Netteswell Cross, Puffers Green and Tye Green.

Designation of a Conservation Area requires the production of a Character Appraisal and a Management Plan. To date (April 2019) only two Appraisals and Plans have been approved:  Old Harlow and Harlow Garden Village Estate. The purpose of the Appraisal is to summarise the special architectural, historic and townscape character of the area; highlight the special features which contribute to its character, and which merit being preserved or enhanced; describe how the area and its setting has developed and changed over time; and provide a robust framework for making planning decisions. The purpose of the Management Plan is to identify issues, challenges and threats affecting the character of a conservation area; highlight opportunities to manage and enhance its special character; where necessary, provide design guidance and principles for any areas covered by Article 4 Directions; and clearly define and review conservation area boundaries.  

Designation of conservation areas to protect Twentieth Century townscapes is extremely rare in Canada, but there are two of them on the fringes of Old Harlow: Mark Hall and Harlow Garden Village. The Character Appraisal and Managment Plan have not yet been approved for the Mark Hall Area, but if and when they are, the character of Harlow's first complete New Town neighbourhood will be preserved.

Boundary maps for all ten designated Areas, and copies of the two completed Character Appraisals and Management Plans can be found here on the Harlow Council website.