Prague, March 1 (CTK) – Researchers from Brno with their colleagues from Iceland and Switzerland are looking for a suitable green roof to meet climate conditions in the Czech Republic, daily Pravo writes yesterday.
Green roofs are common in Iceland and other Nordic countries, where this tradition dates back to the Viking era (9th-11th centuries) as well as in the Swiss mountains. They are also spreading in the neighbouring Austria and in Britain.
Though there are still few buildings with a green roof in the Czech Republic, housing experts say this trend will soon arrive in the country, Pravo writes.
However, it is quite complicated to find the right mixture of plants for a green roof to last long. Those who will use a natural grass carpet from a hobby market on a roof will not succeed, the paper adds.
“We have other climate conditions than Nordic countries, which means that green roofs for Central Europe will differ from those we know, for instance, from Scandinavia. We had to find a tailor- made grass. Green roofs en masse are just a question of time in the Czech Republic,” Petr Selnik, from the University of Technology (VUT) in Brno, told Pravo.
His research team has built a test house in Brno to try which grass roof is ideal for Central Europe, Pravo says.
In Iceland, the roof structure is covered with hydro insulation on which three grass layers are placed.
But this method does not work in the Czech Republic where the precipitation level is thrice lower and the sunshine intensity much higher than in Reykjavik. Consequently, the sun would burn the grass on southern roofs in the summer.
The tests show that the most suitable green roof for the Czech climate conditions would resemble a meadow with corn poppies and thyme in blossom in the Palava locality, south Moravia, Pravo writes.
“A model from the Swiss mountains is the most advantageous to us. A thin layer of a substrate with an admixture of soil is put on hydro insulation. Seeds of plants from the Palava steppes are planted there. We know that exactly these plants will survive the summer heat,” Selnik told Pravo.
The owners only must water their green roofs from time to time. Otherwise such a roof is as resistant as that made of standard burned tiles, Pravo writes.
Selnik points out that a green roof is not only environmentally friendly, but it has also great thermal insulating qualities and besides, the grass on it need not be cut.
