Rehabilitation of the building drainage system in 2018: New market develops - growth of over 70 % compared to 2017
A new market for trenchless sewer rehabilitation is building drainage. In addition to damaged mains and connection pipes, installed underground, downpipes, kitchen and bathroom pipes as well as rainwater pipes within buildings also have an enormous need for rehabilitation. Innovative hose lining and centrifugal spray systems, which have been specially developed for this application, are being used more and more frequently. Scandinavia is a role model. The trenchless rehabilitation of the building drainage system has been the absolute standard there for over 15 years. The new business segment is also developing very dynamically in Germany. In 2018, growth of more than 70 % compared to the previous year was recorded, which can be derived from the sales figures supplied by manufacturers.
While the length of the public sewerage system, at approx. 600,000 kilometres, can easily be derived from statistical surveys, valid figures for private drainage are scarcely available. Experts assume that the length of private property drainage lines is about two to three times that of the public sewer system, meaning that a length of about 1,500,000 kilometres can be assumed. These estimates do not yet exist for building drainage. Experts from trade associations, pipe manufacturers and the industry estimate that, once again, considerably more waste water pipes are installed in building drainage than underground areas. Based on the sales figures, it is assumed that more than 20,000,000 kilometres of waste water pipes in Germany are installed inside buildings. Even if no statistically reliable figures are available, a very high market potential can be assumed when it comes to the rehabilitation of building drainage systems.
Little known about damage profiles and statistics
While it is known from statistical surveys and pilot projects that around 20% of public sewers and probably well over 50% of the property drainage system are defective, not much (yet) is known about the structural condition, damage and damage rates in building drainage. From the trade it is heard that the familiar damage profiles in the case of older pipes made of cast iron or steel are particularly concentrated around corrosion, cracks, incrustations and partly leaky pipe connections. As for first generation plastic pipes, which have been used since the end of the 60s for instance, reports say that these are sometimes brittle. It is known from many fibre cement pipes that these today often show damage in the form of leaks, e.g. caused by cracks and defective pipe connections. In this context it should be noted that, in many waste water networks, a normal operating life of more than 50 years is (far) exceeded these days.
Nine hose lining and centrifugal spray systems already with DIBt accreditation
The trenchless rehabilitation of waste water pipes inside buildings with hose lining and centrifugal spray systems is becoming increasingly popular in Germany. Rehabilitation systems used in building drainage must meet the structural requirements placed on the procedures in order to obtain a generally valid building approval from the DIBt (German Institute for Structural Engineering). In particular, the products used must meet the requirements of building material class B2 for normally flammable materials and have sufficient temperature resistance (e.g. for discharging hot kitchen waste water). The DIBt has already approved nine hose lining and centrifugal spray systems for use inside buildings, which allow rehabilitation without chiselling and demolition work in this special application (see www.dibt.de). Other systems are currently not yet approved, such as short liner products.
70% market increase in 2018 compared to 2017
The trenchless rehabilitation of building drainage with hose lining and centrifugal spray systems has been the absolute standard in Scandinavia for over 15 years. In Finland alone, a turnover of more than 120 million euros was achieved in this market in 2017 with over 1,000 industrial employees at over 85 companies. These figures extrapolated to Germany would theoretically mean an annual volume of more than one billion euros in the national market. For about two years now, various players have been undertaking activities to develop this new business field in Germany. Among others, real estate owners and companies, industry, architects, technical building planners and structural engineers are thus being made aware of the still little known technical possibilities and alternatives to traditional chiselling and demolition work by being provided with information. With success! In 2018 - not least against the background of the above-mentioned activities - many projects aimed at rehabilitating the building drainage system were already implemented. Based on the sales figures of the products developed specifically for this application, a market growth of over 70 % compared to the previous year can be derived. Tendency continues to rise sharply!
Outlook for 2019: Growth, public relations, rules and regulations and work guidelines
Further market growth is also expected in Germany and throughout the EU in 2019. The manufacturers and users of the building products specially approved for the rehabilitation of building drainage systems will continue their efforts to develop the market, e.g. through appropriate public relations work at real estate fairs and in real estate and other trade journals. Furthermore, the possibilities of the trenchless interior rehabilitation of waste water pipes within buildings are increasingly being made known to real estate owners and companies, industry, architects, technical building planners and structural engineers. It is very likely that further manufacturers and users will follow in 2019 and that the technical development of existing products will press further ahead. Many trade associations and regulators are also keeping an eye on the new market. Until now there has been a lack of uniform standards as well as planning and decision-making aids for clients, contractors and engineering offices. Against this background, at a European level DIN and CEN (European Committee for Standardization) are currently working on a Europe-wide standard specifically for this area. The publication of national regulations and work guidelines by the RSV - Rohrleitungssanierungsverband e. V. and the VSB - Verband zertifizierter Sanierungsberater für Entwässerungssysteme e. V. is also expected in 2019. All these measures will increase the acceptance and willingness of real estate operators to use trenchless methods to rehabilitate building drainage systems.
Project reports from the year 2018
In 2018, a large number of projects for the trenchless rehabilitation of building drainage with hose lining and centrifugal spray systems were successfully implemented. This included both smaller construction measures, during which individual defective pipes were rehabilitated in a single day's work, and complex construction measures where complete drainage networks of apartment buildings were carried out with construction times of several months.
In the project, up to 50-metre long waste water downpipes, including the opening of up to 26 inlets, were rehabilitated using the hose lining method on each working day. The inversion took place from the roof to the basement. The curing was carried out with superheated steam. The rehabilitation of a pipeline was completed within 4 hours. The inlets were then opened from the inside using a special robot. After 8 hours at the latest, the drainage system was able to be put back into operation.
Over 20 rain water downpipes from DN 100 upwards made of PE-HD in three new buildings by means of hose lining.
Functionality of the existing fire protection sleeves / pipe penetration seals had to be ensured; very bendable pipe runs starting from DN 100
In the project, more than 20 PE-HD rain water downpipes incorrectly fitted during installation were rehabilitated. The functionality of the existing fire protection sleeves / pipe penetration seals had to be ensured, which was tested beforehand in extensive tests. The pipes starting from a nominal diameter of DN 100 featured lots of branches with in some cases more than four 90° bends over a total length of less than 20 metres. The pipes were able to be successfully rehabilitated using the hose lining method. The curing took place based on the existing pipe penetration seal using ambient temperature.
Rehabilitation of more than 400 m of defective downpipes using the centrifugal spray method
Rehabilitation of the drainage system during ongoing residential occupancy in the nominal sizes DN 50 to DN 70
In the project, damaged WC soil pipes were rehabilitated using the centrifugal spray method. Initially, the downpipes were pre-cleaned using high pressure and the BRAWO® Vortex Cutter. Subsequently, the pipes covering over 400 m, each with a length of between 4 m and 20 m, were rehabilitated using the centrifugal spray method with the aid of brush technology. Projects like this are handled several times a year by R + M Umweltservice GmbH from Sindelfingen. In 2018 alone, waste water pipes in more than 30 buildings were rehabilitated by the company using the centrifugal spray method.