A staircase in a historic building is an important part of what makes the building so special therefore it is imperative to know exactly what should be done when it begins to deteriorate in order for it to be kept in full use.
Most defects arise due to general wear and tear, accidental damage, inadequate control of damp, repeated exposure to fluctuations in temperature and humidity or inappropriate repairs. Many of these reasons are risks that can be minimised and the consequences can be delayed using appropriate management and maintenance in the hope to extend the structural safety of the staircase and safeguard its history for as long as possible.
For example, to help to reduce wear and tear through general traffic up and down the stairs a carpet runner can be laid to form a protective layer. Care will need to be taken when fitting this carpet and thought will need to be given as to how this is done to avoid causing any damage to the underlying structure. Excessive moisture and poor ventilation can cause fugal decay. Areas that can be most affected by this are areas of the staircase that border an outer wall or a void over a cellar. Fluctuations in temperature and humidity can cause issues with damp and or lead to issues associated with the drying out of wood. Examples of this would be the loosening of components or splitting and cracking occurring.
Even with appropriate maintenance and cleaning a staircase which is used regularly will need strengthening or repair work in the end. This is most important when the safety of the stairs are compromised. Examples of this would be when the balustrades or handrails have been damaged or when treads or nosings become excessively worn or unstable.
In accordance with English Heritage guidance any repairs carried out should involve minimum intervention. In some instances the existing staircase can be restored with no loss of historic fabric. Unstable treads can at times be reinforced through the addition of secondary support. Wherever possible repairs such as this should be carried out from the underside of the staircase. Some repairs can be completed on site whereas others e.g. a new section of handrail or replacement treads and risers will require the manufacture of new parts.
When adding new timber parts to an existing historic staircase seasoned timber should always be used as this reduces the risk of any potential warping, twisting and shrinkage. When any component is replaced it is imperative that these are a suitable match to what is existing as not to compromise the overall effect.