Monarplan
®
Installation manual
25
062014V1
Membrane Used:
Monarplan® FM
7.4 Mechanically Fastened System
7.4.1 Introduction
In mechanically fastened systems the Monarplan® FM reinforced
membrane is fastened in the overlap seam along one edge of
the membrane and secured directly to the structural deck. The
adjacent sheets of membrane are then hot-air welded to provide
the continuous waterproof covering.
The membrane is protected from mechanical damage by using
an tubular washer or pressure plate in conjunction with the
appropriate screw fastener.
For confirmation of the appropriate size of washers and fasteners
to use, refer to the Icopal Fastener product datasheet.
Prior to application of the Monarplan® FM reinforced membrane,
a wind uplift calculation must be carried out in accordance with
EN 1991-1 to -4 or to the corresponding national regulations to
determine the correct fixing centers specific to the project.
In case of refurbishment, an individual calculation should be done,
if necessary based on pullout tests of the fastener manufacturer.
On non-ventilated roofs, fastening of the membrane at the same
time provides fastening of the thermal insulation.
If the insulation boards are not sufficiently secured in this way
(min. 2 fasteners/m²), they must be additionally fixed prior to
installing the membrane.
Where the substrate comprises profiled metal sheet, the
waterproof membrane should be fixed at right angles to the
longitudinal rib of the metal profile.
7.4.2 Methodology
Prior to and during membrane installation, inspect and correct
the substrate; (i.e. voids or gaps, uneven conditions, and any other
surface irregularities that can cause voids in the weld).
Side Laps
Position sheets so they run square and with sufficient overlap
to the adjacent sheet. In the case of the mechanically fastened
system the side lap should extend a minimum 50 mm past the
fastening plates / washer. The weld must have a compulsory
minimum width of 20 mm.
Checking the seams is a compulsory action at the end of any
area of work. The welded seams have to cool down to ambient
temperature before probing.
When the sheets are fastened mechanically, a minimum 10
mm free zone between the fasteners edge and the edge of the
membrane must be observed. The minimum overlap should be
110 mm (if the width / diameter of the washers is not more than
40 mm). If washers are wider, the overlap is increased accordingly.
The overlap is calculated in following manner: 10 mm free edge
+ width of washer (45mm for a Tube Washer) + 50 mm welding
zone.
Monarplan® FM membrane
Insulation board
Icopal Vapour Control Layer
Trapezium steel roof deck
