ELEMENT FOR TURFED ROOFS

Abstract: Element for laying turfed roofs, preferably with an inclination of less than 45 DEG , or outdoor areas, the element comprising growth turf or other turf material surrounded by a water and air permeable material, preferably sacking or netting.

Description: Element for turfed roofs. The present invention concerns an element for making -turfed roofs, covering inclined areas such as hills or mounds outdoors etc. , and where the element in addition is suited as a growth substrate "which is not eroded from the roof or the sufrace on which it lays. It is previously known to use peat or turf on roofs both for sound-proofing and isolation. It is thus known from DE Off. Schrift No. 3.510.318 to use turf mats containings glass wool for covering roofs with an inclination of more than 45" . It is, however, not known from this publication to contain the turf mats in a surrounding sheath to contain the turf material more easily. The problem which represents the basis of the present invention is that turfed roofs often are used on climatically exposed buildings such as mountain cabins. When laying such a turfed roof it has previously been common practice to use a loose layer of turf or cut turf or peat mats which afterwards are sowed with grass and plant seeds and optionally covered with a netting to prevent wind or water scouring of the the turf or peat material. In practice, however, this has not been sufficient since the turf already at the laying has had a tendency to become eroded, and in dry weather large amounts of the turf has blown away before the grass or plants have rooted themselves sufficiently to secure the turf material. Another problem in laying turfed roofs with such conventional turf mats has been that they have a tendency to disintegtrate during handling so that the construction worker remains standing with loose and unusable peat dust. This is especi¬ ally true with turf mats. In addition to this type of problems with dry turf material, such turf material when wet may ooze down or possibly be flushed away during rainstorms. The purpose of the present invention is thus to produce a turf material which is suited for laying turfed roofs, especially in exposed places, which does not erode and which is especialy suited for laying roofs with an inclination of less than 45" . This purpose is achieved by including growth medium with a large water- and air capacity in a sheath which may secure the turf material. Such a sheath may inter alia be a netting sack with a mesh opening of 1 mm 2 to 1 dm 2 . The material of such a netting bag or sack may comprise plastic, sacking etc. The laying of such a roof may be done by, after having performed the necessary basic work on the roof by laying sufficiently waterproof and lasting base layers such as tarred board and/or plastic foundation plates etc. together with necessary edge boards, preferably in impregnated materials, laying the above described filled netting sacks closely together on the roof. Possible spaces between the sacks are filled by using the contents of some sacks as filling material or by using other suited material for such use. Thereafter the roof is sowed with suited seeds, inter alia grass seeds, and the seeds are covered with a thin layer of growth turf, growth earth, etc. , and the material is then supplied with sufficient moisture through rain or watering. Alternately, the grass or plant seeds may be sowed directly on the netting or sacking material. Enclosed are in addition figures showing examples of the construction and use of turf covering sacks according to the invention, wherein: Fig. 1 shows the construction nof a turf sack according to the invention, Fig. 2 thows a cross section of the placement of turf covering sacks according to the invention on a base treated roof, Fig. 3 shows an overview of a partly covered turf roof with a covering material according to the present invention. In fig. 1 the reference number 1 represents the surrounding material Df netting or sacking, preferably with a light opening of between 1 and 100 mm 2 , around the medium 2, comprising inter alia growth turf. In fig. 2 the reference number 3 represents loose growth medium used for filling out the space between the turf sacks according to the invention. The numbers 5, 6 and 7 repre¬ sents edge boarding, drains and water-proof base of the roof 8 , respectively. In fig. 3 there have been used the same reference numbers as in fig. 2.

Claims: C l i s 1. Element for laying a surface-protecting turf layer, c h a r a c t e r i z e d i n that it comprises turf material with large water and air capacity surrounded by a sheath -which is permeable "to air and water. 2. Element according to claim 1, c h a r a c t e r i z e d i n that the sheath comprises netting with a mesh size between 1 mm 2 and 1 dm 2 . 3. Element according to claim 1 or 2, c h a r a c t e r i z e d i n that the sheath comprises plastic or sacking material. 4. Use of element according to each of the previous claims for laying roofs with an inclination of less than 45°.

Inventors: ORDING ALF, ORDING, ALF
Applicants: NITTEDAL TORVINDUSTRI AS, NITTEDAL TORVINDUSTRI A/S
Application year: 1990
Main classification: E04D7
IPC codes: E04D11