Istanbul brings together the densest construction and the most varied ground conditions in Turkey. Near the Bosphorus, soils close to sea level carry a high groundwater table, while further inland different geological layers create different drainage needs. Our team provides foundation drainage, basement waterproofing and roof insulation across Istanbul, particularly in Kadikoy, Besiktas, Uskudar, Sariyer, Bakirkoy, Maltepe and Pendik.
Intensive urban regeneration and the spread of basement car parks in high rise buildings have both increased the need for professional waterproofing. Sudden, heavy rainfall is also becoming more frequent, which makes the correct design of surface drainage systems more critical each year.
Istanbul carries high seismic risk because of its proximity to the North Anatolian Fault, and that raises the importance of ground stability alongside waterproofing at building foundations. The damage seen in the region during the 1999 earthquake showed how critical correct insulation of foundations and basement floors is for the life of a structure.
Ground conditions differ across the city: alluvial, moisture laden soils along the coast, and firmer but locally permeable rock formations inland. Before every project our team assesses the ground and climate conditions specific to the area and selects the appropriate material and application method.
The three situations we meet most often in İstanbul
Plots where excavation is impossible. Dense development means the outer face of the retaining wall cannot be reached in most buildings. The solution is then built from inside: active flow is cut off by injection, a system that works on the negative side is applied to the wall face, and where necessary a collection channel and pumping chamber inside the basement reduce the pressure.
Deep basements and car park levels. In multi level basements the lowest floor is exposed to high water pressure. The lift pit, as the deepest point of the building, must be treated as a separate detail.
Highly variable ground. Ground character changes markedly from district to district across the city. Near the Bosphorus and Golden Horn shores the water table is high, while on the ridges and rocky sections the picture is entirely different. For this reason no single prescription works in İstanbul, the decision is made plot by plot.
What we look at during the survey
Access for excavation at the outer wall face and distance to neighbouring buildings, the number of basement levels and the lowest floor level, the condition of the lift pit and plant room, the height of existing damp marks, the age of the building and any previous interventions, and the conditions for working in common areas under the management plan.