By Noel Omollo Okello
Floor finishes are the directly visible material surfaces of completed floors. Though some authors conflate floor finishes with floor coverings, they are different: Floor finishes are integrated into the upper surface of composite materials of floor slabs to fulfil the general performance criteria required of floors whereas floor coverings are installed or fixed onto the completed floor surface to serve specific or secondary purposes. Screed and ceramic floor tiles, for instance, are floor finishes which are often used on entire floors; floor mats and Persian carpets are floor coverings that are often used to demarcate entry points from points of arrival and functional space from circulation space.
General performance criteria for floor finishes include requirements such as the structural integrity to support dead loads and imposed loads, general aesthetic qualities including their range of colours, textures and patterns, impermeability to penetration of subsurface moisture, desirable acoustic qualities such as sound insulation properties, fire resistance, and the ability to resist material deterioration due to exposure to weather elements.
Before I discuss various floor finishes and how they are used in Kenya, it is important to address questions regarding the import of floor finishes and how they can be applied in the design of buildings.
Architecture comprises three planes; the overhead plane (roofs, ceilings, canopies, the sky), the wall plane (fences, barriers, screens) and the floor plane (paths, slabs, bridges). Arguably, our most intimate, but often overlooked experience of architecture occurs on the floor plane. This, perhaps, may be due to the fact that the floor plane is below our line of vision. But other plausible reason may go beyond our sense of sight, or visual laws, to the way our experience of the environment is determined by how our other senses are affected by the floor plane.
We connect with our environment through five senses; touch, smell, sight, hearing and taste. In addition to these senses, sensations of movement inform us of our position relative to the elements of the built environment and also aids in appreciating and apprehending our environment through these cardinal senses.
The Floor Plane and Senses
The floor plane and, by extension, the floor finish, simultaneously enables peripatetic penetration of space (going through a room, going around a column, going down to the sunken lounge, climbing onto the balcony) or bodily pause in space and facilitates our direct sensation, through touch, of our immediate surroundings. The floor plane may also communicate movement through the sense of hearing. For instance a suspended front porch made of wooden slats, or a gravel walkway, by emitting sounds of walking feet would signal the arrival of visitors before they knock on the door. Floor finishes may also be applied in such a manner as to aid wayfinding in buildings: a colour-coded strip on the floor or a floor finish with requisite signs may lead people to a given department. Floors may have heating installed so that during cold seasons residents may feel comfortable stepping on the floors with bare feet. Floor materials may emit certain smells that over time come to be associated with space. For instance a cedar strip floor stained and coated with polyurethane varnish for a lounge may remind a resident, years later, of that lounge when they encounter a similar smell. Floor finishes and floor coverings inevitably absorb spills and the smells of cleaning fluids of various kinds over the duration of their use. They are, thus, a default store of everyday memories communicated through touch, hearing, smell and vision.
Due to this ever-present and intimate mediation role it fulfils between the human body and the environment, the floor plane evokes some of the most vivid sensual and spatial associations. For instance cold, hard and damp floors trod upon with bare feet are associated with dungeons and hardship. Similarly, warm soft fuzzy floors are associated with relaxed living and hallowed religious space while softly reflective and subtle floors are associated with the hygienic environments required in tech manufacturing and hospital theatres. These mental associations are both the means and the result of the realization by architects of how floors can be put to use, for instance, for harsh carceral punishment, soothing medical recuperation or needful spiritual edification.
Choosing the Right Floor
The choice of materials for floor finishes though it may be considered by many in the building industry to be a financial and technical decision, is primarily a sensory decision. Though funds spent on a floor finish may be long exhausted, the effect of the floor finish on the senses lingers –sometimes until the time the building is demolished. Some of the considerations that architects make with regard to floor finishes include:
- the function of the space in which the floor finish is to be applied,
- the local context in which the building construction is done and the locally available materials,
- whether the space is interior space or exterior space; public space or private space, mono-functional or multifunctional.
- sustainability which subsumes considerations such as whether floor finishes can be recycled after the building is demolished, the carbon footprint of processes involved in their manufacturing, and how their application helps in energy conservation within and outside buildings,
- the live loads and impact loads the floor finish is expected to carry,
- the ease of cleaning of the floor finish.
- the kind of exposure to natural elements the floor finish is expected to withstand,
- the aesthetic qualities of the materials of the floor finish and the style of interior being designed for whether modern, postmodern, neo-classical and so forth. Each style has a distinct material expression, and,
- safety with regard to providing sufficient friction to enable locomotion, containing chemically benign materials with consideration to human health, allowing the installation of special services that the floor may be required to contain such as electrical wiring, telephone cables, plumbing, underfloor heating and so forth.
- The cost of floor finishes. The comprehensive costs include cost of purchase, cost of transportation, cost of installation, costs of maintenance over their useful lifespan of a building. The costs of floor finishes vary greatly depending both on their type and their quality.
In terms relevant to floor finishes, space (including that in rooms) is of two kinds; functional space and circulation space. Broadly speaking, these categories of space are distinguished by idioms in architecture such as Moughtins “the street and the square”.
Function of Rooms and Spaces
Multifunctional spaces contain many functions: cooking, meeting, meditation, learning and so forth. Monofunctional spaces contain one main function, for instance stores contain storage.
Though in reality, the main rooms in houses are multifunctional (for instance people sit, eat, sleep, listen to music, talk, dance, and so forth as part of “living” in living rooms), functional space is space in a room that is actually used for the primary function for which the room is intended. For instance, in a bedroom space that is actually used for resting and sleeping is considered functional space. Circulation space is space in a room that is used for access and movement. To get across a lounge into the dining room the residents of a house use circulation space.
In architectural design, functional space may be distinguished from the circulation space applying different floor finishes and/or floor coverings. In some upmarket residences, the sitting area of a lounge may be distinguished by a Moroccan rug while the circulation area around it is marked by non-slip ceramic tile floor finish. This makes sense because circulation space on the floor plane encounters higher pedestrian traffic and would require relatively more durable material finishes such as terrazzo, screed and ceramic tiles. Public spaces in a house too, for instance hallways, lobbies and stairwells, require more durable finishes as both residents and visitors use them more frequently. Private spaces on the other hand require warmer, customized, and more aesthetically appealing materials such as timber parquet, floor laminates, and strip flooring. In all these cases the materials chosen for the floor finish should contribute positively to the aesthetic effect of wall and ceiling finishes.
Floor finishes that are obtained close to the site of construction and made of local raw materials obtained through environmentally sound methods are more desirable relative to imported garish floor finishes. Their properties are well-tested and known over time by local craftsmen, they are easy to replace after their useful life is over, their use promotes local skills and local industry, they are unique, and their closeness to the site reduces transportation costs.
Interior or Exterior?
Floor finishes in rooms and areas exposed to moisture and direct sunlight are prone to mould and fading. Generally, floor finishes for areas exposed to moisture and solar radiation should be relatively be more resistant to moisture penetration and material deterioration. Floor finishes for exterior spaces, as they are more exposed to these weather elements, ought to be permeable to allow stormwater percolate into the ground, but resistant to weathering and the growth of mould. Terrazzo, stamped concrete, brick paving, concrete paving, exposed aggregate, quarry tiles and stone flooring are commonly used on exteriors due to their durability, resistance to mould and weathering. However, they form impermeable surfaces that prevent water percolation into the ground.
Common Mistakes in Kenya
Having shared something about design considerations for floor finishes it is useful to suggest some of the common mistakes made in selecting floor finishes for residential buildings in Kenya according to my experience as an architect. They include:
Overlooking building life-cycle maintenance requirements: All buildings require maintenance over their lifespan. Construction is both a laborious and financially demanding undertaking. This fact ultimately skews building cost considerations towards severe cost control or building construction cost minimization measures. Due to the escapist but ultimately problematic decision some clients make to lay emphasis on the costs of labour and material purchase many clients take maintenance costs for granted. Some floor finishes may be cheap in the short run but would require frequent replacement particularly in circulation spaces with high pedestrian traffic. Many cheaper materials are imitations of other materials. For instance, concrete may be finished so that it resembles wood or plastic made to resemble ceramic floor tiles. It is not illegal to apply these materials in construction, but their application carries the risks associated with their novelty. Where these materials are imported, they may eventually be hard to obtain in local stores, forcing the client to replace entire floors or end up having to live with the aesthetic of a patched-up floor.
Applying interior floor finishes to exterior spaces: Some building owners use superfluous interior floor finishes on exterior spaces, for example, ceramic tiles on balconies and terraces. The problem with such application is that exposure to weather elements causes rapid material deterioration. These materials often affect the immediate environment by reflecting solar radiation onto flora and fauna or reflecting the sun onto the faces of those who use the exterior spaces onto which they are applied. Such application often fails to match with the aesthetic of the exterior façade of a building and with the surrounding green. Most worrying is that they are dangerous to walk on when it is wet. Which brings me to the next point.
Applying slippery floor finishes in public spaces and wet areas. I have never understood why slippery floor finishes are knowingly specified for public spaces. Or kitchens. Or bathrooms. It’s not only dangerous; it is senseless. One of the tenets of universal design is that public spaces should be safely accessible to all including children, the elderly and the disabled. Since slippery floor finishes in wet areas are essentially death traps it is of utmost importance that only non-slip finishes be specified for wet areas.
Poor workmanship: In building construction, you get what you pay for. Some clients opt to employ unqualified individuals as installers of flooring in order to save costs. But they get what they pay for: problems crop up with the floor finish. Poor levelling, crooked alignment, cracked ceramic tiles, peeling polyvinyl tiles, loss of adhesion, chipping wooden floors, streaks, leaks through the suspended floors of wet areas and so forth.
The author is a director at the architectural and urban design consultancy firm Intricate Design and Build Limited located in Nairobi on Ndemi Lane. He is rescued, lately, from the belief that (formal) learning has to suck.