What characteristics should an external staircase have? As with external floors, the staircase must also:
► resist frost
► not be slippery
These two requirements cannot be waived, so the staircase must be designed and built to meet these two criteria. 
The materials used to cover the steps must also respect these two fundamental criteria.

But there are also some requests that we usually receive, such as:
► the steps must not be too easily soiled
We are outdoors and therefore have to deal with dirt, leaves, dirty shoes... for the same reason:
► the steps must be easy to clean

The function of stairs in the exterior of the house is to facilitate the vertical movement of people around the building, allowing them to overcome differences in height. 
External stairs can be of various types, for example:

• entrance staircases
• secondary stairs
• external stairs leading to an entrance on an upper floor

The last type of staircase is perhaps the least common nowadays because the tendency is to insert stairs leading to upper floors inside. This was not the case in the 1960s when many houses had an external flight of stairs made of concrete or metal, on which concrete or stone steps were then placed. 

The most common types of stairs are the first ones, those that compensate for a slight difference in level in the garden between the living area and the street. The entrance staircase has a decisive influence on the home and must be carefully studied and designed. It is usually connected to an entrance, which can be a porch, and to the pavement that surrounds the house. 

Generally in this type of staircase, the calculation for determing the riser and tread provides for deeper treads and slightly lower risers. The width of the staircase/ pathway is usually about 100/120 centimetres and the materials chosen range from porphyry to prun stone and porcelain stoneware. 

External service stairs are used as a connection between the ramp of the driveway and the pavement of the house, or to compensate for the different levels of the pavement, or at the back of the house to connect the living area to private play or relaxation areas. In these cases, deep steps are generally not created, but the ratio between riser and tread is the classic one (30 cm tread and 18 cm riser).

What materials for an external staircase?

Here at Pellizzari we have a wide choice of materials that can be used to build an external staircase in the garden. Some are also suitable for solid use, others are only suitable for covering a concrete staircase. 
Let's take a look at some of them:
► Prun or Lessinia stone
► Trentino porphyry
► Luserna stone
► Tibetan stone or Indian quartzite
► Porcelain stoneware

 In the following articles and in the gallery you will find ideas, photos and suggestions on the world of outdoor stairs. 

What materials for your external staircase?

Each material has its pros and cons.

Porphyry has the best slip resistance, but you need to like a rather rustic look and a dark colour. As a volcanic material, it can easily withstand frost and weather, but is difficult to work with due to its extreme hardness.

White prun stone (as well as trani or vicenza stone) is very refined, extremely elegant and can be shaped, worked in bullnose or to create rounded steps. Unfortunately, like almost all marble, it is absorbent and, over time, frost, the use of aggressive detergents or de-icing salt can ruin it.

Stoneware does not have a rough, non-slip surface like porphyry, but it is just as frost resistant and does not stain. It has a reduced thickness (usually 1 cm, but nowadays there are also 2 cm thick stoneware tiles) and the dimensions dictated by the size of the tile (although today there are very generous formats thanks to the production technique of large slabs).