Repairs and extensions to listed buildings: a guide for owners
A guide to materials and practices for repairing and maintaining listed buildings.
The quality of the built environment in Uttlesford is very high. Many of the towns and villages have concentrations of listed buildings and their traditional street scenes are of the highest calibre. Thatched cottages and timber barns in the countryside are a reminder of former agricultural traditions. There are about 3,500 listed buildings in the District, representing most historic periods and displaying a wide variety of building styles and materials. Although this number is considerable it is also finite. The Council has a duty to preserve these qualities for both present and future generations.
Listed buildings and the law
A building is listed because of its special architectural or historic interest. The listing applies not only to the building itself but, equally, to any object or structure fixed to it and any object or structure in its grounds which existed before 1948. Thus, boundary and garden walls, gates and other structures such as summer houses may be subject to the same protection even if they are not listed in their own right.
Owners have an interest to look after listed buildings properly. The law relating to listed buildings is complicated but the most important thing to remember is that Listed Building Consent will be required to extend or alter a listed building, both externally or internally in any manner which would affect its special character. Planning permission may also be required for some minor developments in the grounds of a listed building.
The Council actively responds to any notification that unauthorised work may have taken place. Where unauthorised work has been carried out to a listed building, the Council can take necessary enforcement action to make the owner rectify the situation.
Furthermore, it is a criminal offence to carry out unauthorised work and the Council has the right, which it has exercised, to prosecute.
The first impression when approaching a town or village is often the view of its roofs seen from a distance. It is particularly important to preserve this element, often characterised by shapes, textures and colours which have evolved over long periods of time. As with other aspects of repair, the message is to re-use as much of the original material as possible and carefully match in any new elements. Any decorative features on the roof, such as carved or moulded bargeboards or finials, should be conserved and repaired where possible.
In Uttlesford the thatching tradition by the use of long straw has led to very picturesque and distinctive roof forms which significantly enrich the unique character of the District. Despite significant losses in the past, particularly in the urban areas and in the countryside on agricultural buildings, the number of remaining thatched roofs is considerable and represents a major environmental resource which the Council is determined to protect. The Council will not normally grant consent for the replacement of thatch with other roofing materials. Re-thatching should normally be carried out in long straw, unless repatching an existing reed roof. If you are intending to carry out thatching work use an experienced thatcher and ask to see examples of his previous work so that you can assess standards of workmanship, particularly durability.
Tiles and slates
As many existing sound tiles as possible should be re-used and any deficiencies should be made up with matching second hand tiles. Roofs to extensions of Listed Buildings and new development in Conservation Areas should generally be clad in new handmade clay tiles.
Wherever possible, slates should be reused and, if necessary, supplemented by second-hand or new natural slates of the same size, repeating any existing decorative pattern which may exist.
If any patching or making-up in replacement reclaimed materials is necessary, it is usual to retain the original material on the principal elevation pitch of the roof (normally the roadside) and to use replacement material at the rear or on the hidden pitches of the roof, concealed from public view.
Windows and doors
Windows and doors are important elements of the historic and architectural character of any building. In the past many elevations have been spoilt by inappropriate replacements. Nowhere is this more evident than on a terrace of houses where different types of inappropriate windows and doors may have been installed. Repairs to original windows and doors should always be fully considered before contemplating replacement. Such repair work will nearly always be cheaper.
Historic windows should be repaired and not generally altered or replaced. If it is necessary to fit a replacement window then you should retain the same size opening and the same glazing bar pattern. The use of plastic, metal and even stained hardwood is usually unacceptable. Normally painted softwood will be the most appropriate. When installing double glazing, secondary glazing is a better solution than sealed units because the removal of the original frame is not necessary and the external appearance of the original window is retained.
Features such as stone steps, boot scrapers, door furniture, fanlights should be retained even if the doorway is redundant.
Simple historically appropriate styles should be considered for fittings which need to be replaced. Old glass such as crown glass should be saved and reused where possible.
Other building materials
Other traditional materials found in Uttlesford principally consist of red stock and gault bricks, rendering, flintwork and black or white horizontal boarding.
Any brick repair should be carried out in a manner to match the existing. Particular care should be taken to salvage and reuse existing bricks wherever possible. Clay bricks should be used as replacements as opposed to those made of concrete and must match the existing ones in colour and texture. Most importantly the new bonding must match the existing. Only lime based mortars should be used because standard cement mortars can cause problems in relation to old clay bricks. A mortar mix of 1 part cement, 2 parts lime and 9 parts sand will generally be appropriate. Repairs should not be carried out when there is any risk of frost.
Existing brick detailing such as string courses or geometric patterns should be retained and where necessary repaired.
Any repairs should be generally carried out in a lime based render with a smooth wood float finish. Any original pargeting should be retained. The use of new pargeting is generally inappropriate unless a skilled craftsman can be employed. Attempts to parget a cement render generally give a harsh appearance.
Painting the outside of the property only requires listed building consent if it would affect the character of the building. The Council, however, considers that painting your listed building in a harmonious colour does not require consent. When choosing paint bear in mind that unlike modern paints which tend to be impervious, traditional microporous paints over lime plaster will allow the building to "breathe" and may avoid certain problems of damp.
If a listed building has been allowed to deteriorate, the Council has other powers available, which it has also exercised, including one to serve notice to repair an unoccupied property and carry out the work needed to bring the building into a reasonable condition, at the expense of the owner. In extreme cases, the Council could exercise a power to acquire the property by compulsory purchase.
Repair work should match the size, colour and texture of existing flints with lime based mortar. The mortar should normally be a mixture of 1 part cement, 2 parts lime and 9 parts sand and grit.
This should be feather-edged, not shiplap, and painted or treated before fixing. Wide horizontal boards painted white or finished in black tar are traditional. Any existing elm boarding should ideally be repaired in elm.
It is usually in the best interests of the building to preserve as much of the original fabric as possible and to replace only that which cannot be saved. This can also be the cheapest approach. If new work has to be designed you should seek specialist help. In addition, by contacting the Conservation Officer at the Council before contemplating a new extension or starting any work, you may prevent abortive work, save time and achieve a better solution.
Prevention is better and generally cheaper than cure. Undertaking simple regular inspections can prevent small problems developing into potentially major ones. Modest but regular work of maintenance, like clearance of blocked gutters and replacement of the odd missing slate or tile, can prevent long term damage and costly future repairs.
New building works and extensions
The highest standards of design and materials will be required. Any new building or extension will be in scale and character with existing buildings. Normally an extension will have a traditional pitched roof that will be constructed of new or second-hand hand-made clay plain tiles, natural slate, red clay pantiles or thatch. The use of flat roofs, concrete tiles or artificial slate will generally be inappropriate.
Many listed buildings in the District are timber framed and it is very important that timbers in such buildings are not cut or removed when making alterations or building an extension.
Listed buildings in Uttlesford are a very important environmental asset. They are available for our appreciation today and we jointly have a responsibility to pass on this heritage to those who succeed us. This however does not mean that appropriate alterations and extensions cannot occur.