Guidelines for Work on Built Heritage

Exterior

Facade
The facade is one of the most important elements of a building and is an expression of its character and importance. The composition of the facade is reflected in the basic vertical and horizontal arrangement, the distribution of the windows and doors, and in the relationship between its bearing and non-bearing parts. All these elements determine the character of the facade and are an indirect expression of the character of the building as a whole.

Colour of the facade and materials
The renovation of any facade requires ultrasound recordings to be taken. On the basis of the results, a colour study is drawn up by the responsible cultural heritage protection service. It is recommended that traditional materials be used for renovation.
Partial interventions on the facade (e.g. the painting of only a part of the ground floor) are generally not acceptable.

Decorative elements of facades
Decorative elements, whether sculptural or painted, are a constituent part of a facade and they must be preserved and renovated in accordance with restoration principles. If decorative elements are damaged or destroyed, they must be renovated or reconstructed if appropriate documents exist for this. Reconstruction must involve the production of a complete replica of the original elements.

Windows and doors
Windows and doors are important elements of a facade, which is why they must be protected and renovated in their original form, dimensions, materials and colours, as determined by ultrasound recordings. The competent regional office must therefore be informed in good time of the implementation of ultrasound recordings and the colour tone for the painting work selected on the basis of the results.
Windows and doors may only be replaced in the event of damage that cannot be rectified. In such a case, the new joinery and carpentry work must be an exact replica of the original and made using the same dimensions, form, details, materials and colours.
It is especially the case with windows that the manner of the opening of casements must not be changed, nor should traditional be replaced with new glasswork requiring any change to the form, size and thickness of the window frames.

Balconies and oriel windows
Balconies and oriel windows that extend towards the street are important elements of the composition of a facade and give a building its character; they must therefore be preserved in their original state, with all structural and decorative elements intact. If it proves impossible to renovate them, they must be replaced by exact replicas using the same materials as were originally employed. The enclosure of a street-side balcony with glass is not acceptable under any circumstance, since this would alter the character of the building.
Cast-iron railings and other cast-iron facade elements must be preserved and renovated to the greatest possible extent, since it is not, as yet, possible to copy them satisfactorily. The same applies to garden railings.

Uncovered projecting roofs/porticoes
In historical buildings, uncovered projecting roofs/porticoes are an explicit and dominant element of the facade; they must therefore be preserved and renovated in their original form. The may under no circumstances be enclosed by glass or another material, or be removed.

Commercial facades
Commercial facades which reflect a certain period of style, such as historicism, Secession and art deco, must be protected, even if they were added to buildings of a different period of style.

Renovation, or the introduction of new commercial facades, must be subordinate to the architectural characteristics of the building as a whole and to the urban planning characteristics of the street or square as a whole.
All interesting and high-quality details on the ground floor must be included in the renovation of a commercial facade.
Marquees and shades must also be subordinate to the rhythm and arrangement of openings on the facade; they must be built into the shop opening and may not connect several openings together. Marquees and shades on the ground floor of a building must be uniformly designed and colour-coordinated even if there are several commercial premises on the ground floor.
They must be adapted to the existing or original horizontal arrangement of the facade. Commercial facade elements (shop windows, advertising elements, signboards, inscriptions) may not extend over the ridge separating the ground floor from the floor above, unless such an arrangement was envisaged in the original plan.

Inscriptions may not extend over the ridge separating the ground floor from the floor above. Inscriptions should be in Slovene, at least with regard to the translatable part of the name of the premises, such as trgovina (‘shop’), pivnica (‘public house’), kavarna (‘cafe’), etc.

Boards inscribed with an indication of the building’s commercial activity may not be affixed directly onto the facade; holders that enable several boards to be mounted and, at the same time, allow boards to be replaced without damage to the facade should be used. Such holders were already part of the original fixtures of the majority of historical buildings in which any commercial or office activity was carried out.

Signboards that mark commercial or catering establishments must be hung on brackets on either side of a commercial facade, may not extend over the ridge separating the ground floor from the floor above, and may not obstruct pedestrians using the pavement. It is recommended that signboards be adapted in terms of their design to the character of the building, or to be entirely neutral in design. Signboards may not exceed 70×70 cm in size.

Air-conditioning installations must not have any external units, or must be such that the external unit in no way impinges on the street-side facade of the building.

Roofs
The roof is a dominant element of a building. Its slope, covering and arrangement form the characteristic outline of the building, street or town.
The characteristic slope of a roof may not be changed during renovation.
In roof renovation, materials that match the original covering in terms of size, form and colour must be used. It is also recommended that, when renovating a roof, the original covering, where it is in a good state, be re-used for at least part of the building.
Chimneys and other architectural, functional or decorative roof elements such as small towers, roof windows of all types, roof openings, metal spires, pennants, snow barriers, etc. are an integral part of a building; they must therefore be preserved in their original form, even if they no longer serve their purpose.

Interior

In work in the interior of a cultural heritage building, it is work carried out in common areas (staircases and halls) in particular that are subject to supervision and control by the monument protection service. In these areas, all architectural and decorative details, as well as joinery and carpentry work (e.g. entrance doors and doors to apartments and auxiliary premises), must be preserved. Banisters, sculptural and painted decorations, memorial plaques and original fittings such as lights, bells, mailboxes, etc. are subject to particular protection.
New installations (gas, telephone, etc.) must be designed in such a way as to affect the appearance of halls and staircases to the least extent possible.
Changes in apartments necessitated by new apartment-related standards and the needs of individual residents are permitted. However, owners should retain the original sculptural, plaster or painted decorative elements, old ceramic stoves, flooring and other fixtures and fittings from the period in which the building was built. Owners should contact the competent cultural heritage protection service for expert advice on renovation.
The original spatial layout of public buildings that were constructed for a specific purpose should be preserved as much as possible. Owners or investors must otherwise obtain a specification of cultural heritage protection requirements and permission to carry out protection work from the competent regional office of the Institute for the Protection of Cultural Heritage of Slovenia prior to commencing work on protected public buildings.

Instructions for painting work using slaked lime

Plastered surfaces must be suitably prepared prior to painting work. After confirmation from a competent IPCH conservator that there are no special painted elements present, the dirt, dust and old whitewash layers must first be removed. Dust must be removed using water applied under pressure (on facades); however, care must be taken to ensure that the pressure is not too great, that the water jet is not too sharp and that the water is not applied at right angles to the wall, which could cause additional damage. If lichen is detected on the facade, it must be removed using a rough cloth or algaecide. There is also the possibility of destroying it using appropriate poisons (tensides, Juvelit system), although lichen cannot be removed permanently. Since it poses no danger to the facade plaster itself, but only has an effect on the aesthetic appearance of the plaster, painting is not conditional upon the consistent removal of lichen. Recent old whitewash layers may be removed by scraping; however, care must be taken to ensure that the plasterwork is not damaged. All damage must be filled in using fine lime mortar (plaster or cement putties are not recommended).

Preparation of whitewash and painting
Lime whitewash must be applied to walls using a long-bristled brush. The whitewash must be diluted and filtered with a fine sieve; it must be applied to plasterwork in several layers (usually between three and five layers). Since the whitewash is diluted, it can take to the facade more quickly than thick whitewash; the period set aside for painting is therefore not significantly longer than it would be for painting done using thick whitewash. Prior to painting, all the plasterwork must be moistened; it is not necessary, however, for one layer to dry before another layer is applied. If it does dry, the layer must be re-moistened before another one is applied. The first layer of whitewash should be applied in a horizontal pattern, the next in a vertical pattern, alternating thus with each layer. No varnish or any other additive should be mixed into the lime whitewash itself.