External floors

External floors in dwellings: the basic functions

By the term "external floor covering" we mean both the horizontal construction element and the surface covering layer that characterises its aesthetics and functionality. Paving will define the entrance areas, driveways, porches and pavements of the house.

In a house, external paving has several functions: 

• to welcome guests and provide them with an easy and attractive path through the outdoor areas of the house
• to accommodate our car or that of our friends
• to provide manoeuvring space for the entrance to the garage
• manage height differences from the ground level to the entrance to the house, rather than the entrance to the garages
• allow us to have lunch or dinner outdoors, with family or friends
• become a recreational space for children (or adults)

When thinking about outdoor paving we need to consider not only the functional aspects but also the aesthetic aspects so that it can become an interface between the garden and the interior spaces of the house, integrating with both elements. 

Landscape and external floors 

But there are more than just homes. External floors characterise many landscapes around us and have seen cultural, artistic, technical and scientific elements applied to ensure both purpose and visual pleasure. 

Man has been modifying the landscape and nature since ancient times. Just think of the planting of vineyards, terracing in mountain areas, the construction of lakes or irrigation canals... the landscape is a continuous testimony to how we leave our mark on the land. 

This is especially true for urban landscapes, where landscape designers must work with functionality and aesthetics in mind, looking for materials, colours and surfaces that are durable and that take into account not only the functions the pavement will have to perform but also seasonality, natural and artificial light.

Our job, which we will do together with you, is to combine natural and artificial materials, trees and stones, with sometimes surprising solutions. 

External floor design: 7 elements to consider

The 7 main elements that I need to consider when composing my external floor design are:

• the shaping of the ground: are there differences in level in the paving that need to be compensated for with external stairs?

• the volumes built (or to be built), i.e. the architectural part of the landscape: porches, pompeianas, gazebos, entrance coverings...

• the vegetation that will be planted. Here you will have to help us by explaining how you want your garden to look, what the flowerbeds will look like or what plants you would like to plant. Then it will be up to us to consider many aspects: habit, shape, colours, change of season... Arboreal curtains can define spaces, shelter entrances, shade porches;

• the paths, their size, the layout, how they wind through the garden or around the house: do you prefer them to be regular or winding?

• the materials to be used for the external floor: natural or traditional such as stone, artificial such as stoneware or reconstructed stone.

• the geometric shape of the materials chosen: large square or small "opus incertum" format. Or, finally, continuous materials, such as resin-coated pebbles or cast concrete

• the presence of elements to be highlighted, connected or circumvented: fountains, ponds, statues, vases, pools, patios.

Basically, the design of your outdoor paving starts with an analysis of the site and the survey that we will carry out at your home and continues with a comparison, which we will have to do together, of all the aspects listed above, culminating in the executive details that will make your outdoor space unique.

This is a real discipline called Landscape Architecture, which involves the use of skill, experience and creativity to design and implement an open space in all its elements. 

Outdoor floors, small and large 

There are several spatial scales on which external floors operate: 

• spaces reserved for mobility: pedestrian areas, pavements, bus and metro stops;
• public spaces: squares, arcades, walkways, avenues; 
• urban parks, children's playgrounds, a skate park... each with a suitable outdoor paving;
• gardens of residences: paths crossing private green spaces and requiring paving;
• terraces, large or small: here the outdoor paving is perhaps complemented by a green roof;
• spaces of memory and spirit: monuments, memorials, religious spaces, church squares;
• city waterfronts;
• industrial archaeology spaces, places of industrial memory;
• ephemeral outdoor spaces, those that are designed and created for an event or demonstration, and that last only a few days.

The materials to be used in the various outdoor pavings listed above must take into account the purposes and requirements of durability or flexibility, and must respect aesthetic canons or the need for accessibility to underlying plant networks.

In short, when choosing outdoor paving it is necessary to keep in mind the purpose of the outdoor space and the stresses to which it will be subjected; it is necessary to design taking into account the nature of the intervention and the transformations it will undergo over time. 

The garden path and sensations 

The garden is also a place that engages our senses: the sound of water, the warmth of the sun, the rustle of leaves. Close your eyes and imagine that you are walking through the garden of your new home in the evening, with the lights on, casting shadows on the floor and plants, and hearing the sound of water from the irrigation system... and try not to get excited. 

Life can be very stressful.
But parking in the driveway in the evening, closing the car (and the problems of the world) to walk home listening to your footsteps, in silence, is a beautiful moment. 

If you've managed to imagine all this, the question now is: "What outdoor pavement were you walking on as long as you imagined?"

Designing external floors

Designing an outdoor pavement requires transversal and multidisciplinary knowledge.

Architecture must be combined with botany, geology, engineering... this doesn't mean that we are all-knowing, but that we have to coordinate different information, we have to synthesise different areas of knowledge and we do this with the design of your external floors. 

We have to know the characteristics of the stones (basalt, porphyry, flint, slate, Serena stone, Prun stone, Trani stone, etc.) or the tiles or interlocking paving slabs we are going to use, and we have to understand whether, and how, to combine them. We need to know which thicknesses to use according to the type of traffic they will be subjected to: pedestrian only, light driveway or heavy driveway? And then the installation: what materials should be used for bedding, what materials should be used for grouting joints? How (and where) should joints be made?

What material for external floors? 

Two pieces of advice:

The first - and this applies to every choice in construction - is to use durable materials and techniques. Roman roads are proof that you can do very durable work if you want to.
Building, especially during construction, is one of the most polluting activities there is, much more so than industry. 
Don't spend too little to buy a floor covering that in ten years' time will become waste, perhaps difficult to recycle or reuse. Instead, choose a product that costs more and lasts a lifetime. You will be doing yourself and the environment a favour. 

The second tip is to consider the "environmental cost" of your choice. If tons of CO2 are emitted to produce the material you are going to lay as a floor or if you have to pollute to dispose of it once its life cycle is over... well, avoid it.

If you are undecided between porphyry and a self-locking concrete floor, consider also the impact on the environment of both choices, both to produce your floor and to destroy/recycle it when it becomes waste. 

Natural materials for outdoor pedestrian areas: stone and wood 

There are many marbles and stones that can be used for your outdoor paving. Each marble, each stone has its own nature, its own character, its own evocative power. Stones perfectly represent the concepts of "naturalness" "authenticity" and are also - since time immemorial - status symbols: the porphyry disc is an emblem of divinity, because of its purple colour and its hardness. Stones can symbolise eternity (pyramids), memory (triumphal arches) and sacredness. You need to take this into account and find the perfect harmony between technical properties and emotional aspects. 

Don't just ask yourself: "What are the technical characteristics of this outdoor stone?".
Also ask yourself: 'What character does this stone have? What emotions does it evoke in me? What does it evoke and represent for me? 

Prun stone 

Prun stone has been widely used in our area since Roman times, even for outdoor paving. This is an autochthonous stone from the Lessini mountains that is well suited for paving pavements, under porticoes, steps and pavements. The most commonly used finish is graffiata in the standard 50x50 and 50x100 formats. We can also find it in the straight grooved finish, bushhammered or, for more rustic situations, in the split quarry finish.
A characteristic feature of Prun stone is the passing veins that in the long run, during thawing and unfreezing cycles, can lead to some minor cracks in the surface.

PRUn stone

Trani bushhammered

If I want to be more sure of the durability of my floor I will have to switch to a more compact marble such as Trani, giallo d'Istria or Malaga. These marbles are much denser, have very few passing veins and therefore react better to freeze-thaw cycles and atmospheric stresses.

Porphyry

One of the materials that offers the best guarantees for use as outdoor paving is porphyry: frost-resistant because it is of volcanic origin and non-slip because its surface is "hollow split", it is also perfect for pedestrian routes, such as paths or pavements. 

porphyry

Wood for external pedestrian floors

If you're looking for a "warmer" floor, you could consider wood decking: there are parquet floors that are very resistant to humidity and temperature changes and, for this reason, are suitable for outdoor use. Alternatively, there are treatments that make wooden planks resistant to humidity. 
The uses can be many: think of the beach area of a swimming pool or a large terrace where you want to walk barefoot. Decking will make these areas look elegant and refined: it will be like walking on the deck of a yacht. If this is the floor for you, you'll find all the information here:

exterior wooden floors: decking

External floors and artificial materials: stoneware, wpc, concrete...

If you, over sentimental aspects prefer functionality, practicity and a minor cost, you could chose to realise your external floors with stoneware or wpc or self-locking.

External stoneware floors

Stoneware is capable of imitating both the surface and stone drawing guaranting, furthermore, a very low (none susbtancially) porosity. The total inapacity at absorbing fluids makes it untouchable to ice and also not stainable. So we can use it when the external floor is going to hospitate luches or dinners with friends: if coffee, wine or cola falls, no problem.

It exists external stoneware that imitates rustic stones, others imitate slate, quarz, porphyry.

Other external tiles that imitate wood decking

Se agli aspetti sentimentali preferisci la funzionalità, la praticità ed anche un costo minore, potresti scegliere di realizzare i tuoi pavimenti esterni in grès o in wpc o in autobloccanti. 
 

Outdoor stoneware flooring

Stoneware is able to imitate both the surface and the pattern of stone, while also guaranteeing very low (essentially zero) porosity. The total inability to absorb liquids makes it frost-proof, but also non-stainable. We can therefore use it without any problem if the outdoor floor is destined to host lunches or dinners in company: if wine, coffee or coca cola falls, no problem. 

There are outdoor stoneware tiles that imitate rustic stones, others that imitate slate, quartz, porphyry. Other outdoor tiles imitate wood decking or metal surfaces such as corten or iron. If you need more information, you will find everything here:

outdoor stoneware flooring

Outdoor wpc flooring

Another "artificial" alternative is wpc: a mixture that imitates wood decking for exteriors, nice to walk on barefoot, warm to the touch and less delicate than real wood decking. We have dedicated an in-depth study to this subject here, where we also present several completed works:

WPC outdoor flooring

Self-locking paving for exteriors 

Concrete block paving, also known as "concrete", is becoming increasingly popular among outdoor paving. Self-locking paving, which in some cases imitates natural materials, guarantees a much lower price also for the laying system, which is much less expensive. Whereas stones or porphyry have to be 'cemented' into the ground, the self-locking block is laid 'dry' on a simple layer of recipe (crushed stone). In short, the price is the strong point of this product, which is why it is used more for large driveways than for pedestrian paths or pavements. You can find out more about this product by clicking here:

AUTOBLOCking

Suitable materials for external driveways

Pavements suitable for driveways must have certain important characteristics 

• Obviously be frost-resistant and non-slip
• They must have excellent mechanical resistance to abrasion and to the continuous passage of vehicles. 
• Suitable colouring, tending to be dark, to limit the view of tyre marks
• Easy to clean and restore 

Natural materials for external driveways

Among the natural materials that meet the conditions required for an external driveway we can find Trentino porphyry, Colli Euganei trachyte and Luserna stone, all of which meet the characteristics described above. 

In many cases, we also find these materials in the streets of historic centres or squares of municipalities and cities.

Another very important feature is that these materials are "self-cleaning" outdoors, in the sense that all it takes is a good, heavy rain to remove the dust and dirt deposited on them. 

Artificial materials for driveways

Artificial or reconstituted materials include stoneware (preferably thick stoneware), or self-locking brick.

At the moment stoneware is mainly used for private driveways where 2 cm thickness is used. The 3 cm or 6 cm thickness is not yet used and has not yet become widespread.

Self-locking paving (in Vicenza and Verona many people call it "Betonella") is used when we have to cover very large surfaces, such as car parks, pedestrian walkways, squares in shopping centres or industrial areas etc. 

Concrete tiles are the ones that guarantee the lowest cost (approximately 30 € per metre) and also speed of laying combined with ease of removal for any maintenance services. The disadvantage is the durability of the floor, which is less than that of stoneware or natural materials.

External floors: laying

Pavements are works of art, and the way they work together is also a matter of knowledge that has been handed down over time and has evolved into a true art. Theory is certainly important, but craftsmanship and experience are invaluable. 

Think about it, it's a bit like if a friend of yours explained to you how to make tortellini... you can buy a book on tortellini, you can download the recipes but... making tortellini in a way that works aesthetically and with the right flavour is a work of art. 

Just as with tortellini, an outdoor floor requires the right ingredients, raw materials and manual skills, and you need to have made mistakes and learned how to put them right. As with a recipe, you need to know the right times and how to handle the unexpected, a downpour or a day of excessive heat.  

The art and science behind these activities, the paving, God knows how long it takes to get it right. How many bad tortellini and how many bad floors do you have to make before you learn? 
We always say that if the paving is badly done, you may have chosen the most beautiful stone, but your choices are all in vain. Even the most beautiful design disappears when faced with bad workmanship on site. 

Layers for external floors

It is essential for the success of our projects to have the cooperation of specialised layers who have chosen to dedicate themselves to external paving and only to that. 

Only in this way will they be able to manage the problems of exteriors, which are very different from those of interiors. The care that needs to be taken outdoors must be truly maniacal. And it is quite normal that an outdoor stone layer costs almost twice as much as an indoor tile layer. 

Outdoor flooring: marriage of stone and concrete

Outdoor paving, if you think about it, is a marriage between stone and the concrete that fixes it to the ground.
The two must ask important questions, especially in terms of durability: are they willing to support and honour us every day of our lives? 

The enemies of this 'marriage' are many:

• The air that contains carbon dioxide, sulphur dioxide, nitrogen dioxide....
• Liquids that can get on top of it: citric acid, acetic acid, tartaric acid (in wine), orthophosphoric acid (in coca cola), but also alcohol, ammonia...
• The garden soil also contributes with fertilisers: nitrogen, potassium, phosphorous...

But the worst enemy is frost, even worse if it is accompanied by the bad habit of throwing salt on the floor to thaw it out.
Let's take a closer look at this aspect.

External floors and frost

A porous external floor degrades quickly, but porosity must be avoided both in the materials that make up the floor and in the cement binders that bond it to the ground and that are used to fill the joints.

Every pore, every crevice, into which water can seep becomes a potential source of damage because the water, when it freezes, increases in volume and, in so doing, begins to crack the floor from the inside. As the water turns to ice and increases in volume by 9%, the ice pushes in from the inside, generating an additional crack pattern. The mechanism is self-perpetuating, leading to devastating effects: each additional crack that is generated becomes a highway for the water to continue to degrade the external floor system.

All this is aggravated by the habit of sprinkling paved paths with salt, because salt reacts with the ice, melts it, but in doing so it raises the temperature of the ice and causes the surface area immediately below the ice to cool. This small surface area of the stone, abruptly cooled, will have a different temperature from the rest of the stone and will tend to crack or flake.

This also applies to concrete joints. When grass grows between the cracks, the marriage between floor and binder has already broken down. 

The freeze-thaw cycle then leads to devastating phenomena in both the stone and the concrete that bonds it to the ground. For the latter, there is a technical standard, Uni En 206, which classifies the degradation of concrete with an index called XF. 

Avoiding frost damage outdoors

Floors can withstand frost and remain perfectly intact or they can be weathered and adapt. If we want the floor to remain perfectly intact, we need suitable materials that are ready for the challenge. You need stone with low porosity or materials that are completely impermeable to water (such as porcelain stoneware or volcanic stone). 

If, on the other hand, you are prepared to accept that the stone may age over time, then we can also use marbles or softer stones. In this case you will see the passage of age, the stones may lose a few pieces, the edge will round off, the surface will have a few cracks. This is not necessarily a disadvantage, although in today's 'plastic society' we might think so. The Japanese love aged stones and choose them for their gardens. Many artists or art history enthusiasts prefer buildings covered in the patina of time, rather than cleaned and bleached. This also applies to outdoor paving: the choice is yours! 

One thing, however, that is crucial when it comes to frost damage is the laying technique and materials. Both the binders and the inert material to be used must be chosen carefully, and all technical precautions must be taken to avoid water seeping in under the flooring, which would cause it to detach and lift up when it froze. 

Finally, effective water drainage is very important: the floor must be guaranteed a low degree of saturation. The right slope, in short, saves your life.

External floors: the stresses

When designing an external floor, we must also take into account the stresses it will have to withstand. In the past, the stresses were the passage of horses and carts. Then there were the cars, the light ones of the 1970s and the heavier ones of today. 

If it's a road, we have to understand whether vans or lorries, buses or cleaning vehicles will pass. If it's a house, we need to understand where the stresses are greatest, where the car brakes and bends, or if there is a possibility, even an extraordinary one, of having to access it with heavier vehicles. 

This helps us to design both the surface material and the deep layers, which are very important for support and mechanical resistance.

Designing external floors in a house

Designing outdoor flooring means giving a very precise identity to the house, an indelible, lasting identity. For this reason, exterior flooring projects are not easy.

There are a few things to note down before you start planning: 

• the position of the house,
• the desired style,
• the shape,
• the colour of the external walls
• possible cladding elements (stone, reconstructed stone, brick)

Many people think of an external floor as an expanse of a single material that indiscriminately covers the surfaces, without taking into account the shapes, profiles and forms of the house and garden. In short, it would be a matter of choosing the material (tiles rather than porphyry) and then distributing it everywhere.
But this means creating environments without personality, clones. In addition, the opportunity of highlighting the peculiarities of the house and of making the outdoor paths harmonious is lost. The interaction between outdoor and indoor spaces must therefore be managed differently, by thinking about it and then designing a project.

The outside is an integral part of our home, it represents our personality in some way, it is our business card for all those people who, without being seen, peek inside our garden when (and if) they see the beauty of a job well done.

How to design an exterior 

We have established how important it is to have a complete vision of the context in which the outdoor paving is to be placed. Shape, surrounding colours, possible coverings, paths, shapes... are fundamental elements both for the choice of material and for its layout.  

If the colours and finishes can help me to understand which materials are best suited, the shape of the house can help me to create any cuts, symmetries, decorations that are useful to make the floor more dynamic.... 

Of course, I'll have to consider whether the house is flat or whether I have to overcome slopes, or whether it follows a linear or curvilinear course. All these factors can help me determine the shape of the material and its size.

Another thing that is very important to me is the immediate and easy-to-understand division between external floors for vehicles and those for pedestrians. A difference in colour or shape of the same material is enough to indicate the path of the car and the space reserved for pedestrian traffic. 

A delimitation determined only by the design not only gives style to the external pavement, but also provides a kind of additional safety by highlighting manoeuvring spaces.  

Mistakes in the design of external floors

Errors in the design of an exterior can be many and divided into: 

TECHNICAL ERRORS 

• incorrect installation
• Incorrect slope 
• Wrong material dimensions
• lack of expansion joints 
• Non-freezing material 
• Slippery material 

AESTHETIC-PRACTICAL ERRORS 

• Colour too light and easily soiled 
• Absorbent material, impossible to clean 
• Colour too dark, retains a lot of heat 
• Colour too light and bright, blinding
• Surface too uneven to walk on 
• Style not in keeping with the house 

Mistakes in the design of outdoor flooring can be many and some can even be insidious and only become apparent after a few years. 

A good example of this is incorrect waterproofing of the sides against the ground. 

The perimeter edges need to be protected from the dampness of the ground, which soaks up water not only when it rains but also when the irrigation system regularly carries out its task of keeping the grass nice and green. The continuous presence of water in the supporting concrete causes it to deteriorate and consequently the pavement to deteriorate.   

Another example is what happens in the corner between the floor and the wall of the house. This is a very critical point, prone to movement and sagging. Good waterproofing will prevent rising damp from damaging the masonry.

Mistakes in outdoor flooring: grouting 

A fundamental step for the success of our outdoor flooring is the correct grouting, which has the task of hermetically sealing the passage of water and preventing it from penetrating into the bedding part of our floor.

Grouting stone exteriors

The composition of the grout must be prepared with the right proportions of sand and cement in order to be elastic and at the same time resistant to continuous wear. 

A decisive factor is the weather conditions in which the work is carried out. If it is too hot, the grouting will dry too quickly, creating crusts which will then have to be removed, while if it is too cold, the cement will not be able to harden and the grouting will remain loose. If it rains as soon as we grout, the water will ruin all our work just done. 

Grouting stoneware exteriors

In this case, pre-mixed grout mixtures are used. But even in this case the grout could cause problems. This happens when it is not mixed properly or when it is mixed with an electric whisk at too high a speed. But also if it has been stored for too long, perhaps in a humid environment.
In many of these cases, the grout - once dry - may appear abnormally shaded after application, resulting in an unpleasant stained effect. 

Types of grouting for external floors 

There are several types of grout for exterior floors: 

• Prepared cement mix (Keracolor by Mapei, Fugabella by Kerakoll, etc.). Typical of stoneware floors 
• With sand and cement, a mixture prepared by the operators on site. Typical of natural flooring 
• In epoxy or polyurethane resin. We talked about this in the article: grouting porphyry with resin
• With sand: by spreading sand inside the joints, typical of self-locking paving stones. 
• With polymeric sand: also typical of self-locking blocks. 

How much thickness do I need for an external floor?

A frequent question is how many centimetres of thickness (free space) must be left before an external floor covering can be laid? Depending on the type of floor, different specifications are required:

• For a porphyry or stone floor, approximately 10 cm from the concrete casting is sufficient.
• For a stoneware floor, approximately 6 cm from the concrete casting is sufficient.
• for a self-locking block floor, approximately 10 cm is needed from the subfloor, which must be made of concrete or well-compacted stabilised concrete.

Driveways are the first thing you see when you reach a house and walk along it to enter it. Good, safe, non-slip external paving will give a high quality entrance to the house, making it more valuable and looking better. It is also useful for separating garden areas or creating a path around the house so that you don't get your shoes dirty walking around the garden.

When designing the external paving of a pavement, you need to take into account the strength of the material, durability, that it is non-slip and aesthetically consistent with the style of the house. A good, safe and non-slip pavement leading to the entrance of the house will add value to your home and provide a perfect frame to make it look neater.

Typical outdoor floors are also used to pave driveways leading to garages in the home. Whether they are on a slope or not, outdoor flooring can be made from many different materials that you can discover by clicking the link below!