How well my manhole cover must seal?

A manhole cover should be reliably pressure-tight against daytime water, i.e. natural precipitation such as rainwater, to ensure a dry manhole. In addition to rain protection, increased reliability is also available in the form of flood protection. This is usually guaranteed up to one or even five metres of water column and is indispensable in certain areas of application.

Insulating or sealing the manhole cover, for example by means of completely filled thermal insulation without any cold bridges, reduces the formation of condensation in your manhole. As the name suggests, insulation also helps to retain heat in your shaft or structure, which can be very important in cold winter months. Depending on the situation, professional insulation can also completely prevent the formation of condensation.

Frost penetration is significantly reduced by applying rigid polyurethane foam (PUR) insulation to the inside of the manhole cover. This insulation is injected in liquid form and additionally secured on the underside by a metal sheet, i.e. not just loosely inserted or glued in. The liquid injection means that there are no cavities inside, the entire gap is filled without any gaps and there are no thermal bridges. The insulating material PUR is resistant to mould and rot and is not a breeding ground for vermin. PUR does not absorb water or moisture, so the insulating effect cannot be lost. Always ensure that the material is CFC-free. Problems caused by moisture and frost in shaft structures can best be tackled with insulation in combination with a ventilation chimney and vapour hood.