Last week I wrote about what causes flooding and what we can do to help prevent it. For some communities, both in the UK and abroad living on water, or near water is a fact of life. To avoid being flooded these buildings might be built on stilts or float and adapt as water levels rise. Today’s blog explores these designs.
Floating buildings – Expanded polystyrene is a key component to ensure the house stays afloat. it can either be used to create a slab on the water: or by creating a composite material with concrete:Presumably there are longevity issues with bare polystyrene and that the composite hull will be much longer wearing.
An alternative to polystyrene is to use a reinforced concrete hull: The hull is often left as a void, perhaps filled with polystyrene, with the house constructed above. It is possible though to use the hull as a basement though, as was shown on grand designs: The building is connected to four columns, and can slide up and down these as required by the flood water. This ensures the house stays level as it rises and falls and it obviously means it doesn’t float off during a flood. Much of the design inspiration for these has come across from the Netherlands. In Amsterdam there are entire communities floating on the water, such as the IJburg estate: All of the houses and walkways are connected to steel mooring poles to ensure they stay in place, floating up and down, as the water dictates.
Building on stilts – It may be very obvious how this design works in the floods, but let’s not knock the simplicity. Here are two UK build houses on stilts: Architecturally, building on stilts can be very effective. The top building appears to levitate above the ground due to the slender and dark columns. In contrast the bottom design emphasizes the columns locations with the glazing and wall panels breaking at these points, leaving clear vertical lines through the design. This is accentuated further by the horizontal lines at each floor level, and by the roof line.
All of the buildings featured in this blog have clear architectural / structural overlaps within the design work and must be the culmination of great collaborative working. As more developments creep onto existing floodplains I hope design strategies such as these are utilized and that rather than feeling threatened by more, unpredictable weather and the associated higher flood risks, we actually use it to inspire us. Perhaps we too will create floating communities like those in the Netherlands.