guttapral

guttapral®, laid under bent and flat roof tiles, are the result of a constantsearch for quality in the field of waterproofing of brick roofs. guttapral® satisfies the basic need to ventilate the roof through its continuous waves, from the eaves to the ridge of the roof.
Information
Advantages
  • They ensure proper roof ventilation, eliminating humidity and condensate.
  • The reduce heat transmission and thermal shocks.
  • Light, flexible and resistant, capable of adjusting to structural irregularities.
  • Savings in terms of time, labour and materials.
  • 25-year warranty on the waterproofing*.
  • * If laying instructions provided by the company are carefully complied with.
Description
  • Vacuum-bituminized, multi-layer laminar sheets for laying 18-19 cm bent tiles
Technical Data
Characteristics
Laminar vacuum-bituminized sheet
Size
2,0 x 0,95 m
Thickness
approx. 2,1 mm
Wave pitch
95 x 31 mm
No. of waves
10
Average weight
2,4 kg/m2 ± 5%
Gross surface
1,9 m2
Net surface
1,58 m2
Nailing
See laying instructions
Fire resistance class
B2
Acoustic insulation
20 dB (ISO 140)
No. of layers
16 - 22
Tolerances
± 7%
Packing
150 sheets per pallet - approx. 650 kg
350 sheets per pallet - approx. 1.620 kg
Application

Garantie

PREPARING THE SUPPORT SURFACE

New roof

You can use a continuous, wood or concrete, or discontinuous load-bearing surface. In this case, use a battening with centre- to-centre distance such as to allow each bent tile to rest on the laths underneath the sheet. Then, proceed to checking the planarity of the surfaces, making up for any tolerances thanks to the flexibility offered by the sheets.

Roof under renovation

Thanks to their flexibility, the sheets can adapt to slight defects in the planarity of the support surface. Nevertheless, prior to the laying you need to make sure that such irregularities allow for the sheets and the overlying roofing layer to be properly installed. In addition to the planarity, also make sure that there are no rough areas with concentrated irregularities that can damage the sheets and compromise their efficiency. Moreover, the hooks used to secure the gutters must be positioned beforehand at the ends of the gutters, and specifically underneath.

TIMBER TREATMENT

Prior to laying the sheets, it is recommended to impregnate all the timber that makes up the roof frame which supports the roof with an insecticide and fungicide treatment on all the timber surfaces, in order to extend its useful life.

LAYING THE SHEETS

When laying guttapral®, always start from bottom corner of the roofing, on the opposite direction of prevailing winds. The sheets must be laid parallel to the eaves, moving up stepwise towards the ridge. The sheets must not stick out at the eaves for more than 5 cm.

OVERLAPPING

Lateral overlapping: one wave
Transversal overlapping: 15 cm

FIXING THE SHEETS

The sheets are fixed to the wooden structure by means of nailing using zinc-coated nails guttanit® TS18. Two rows of nails are driven in, parallel to the direction of the transversal overlapping at the end of each side of the sheets, always inserted from the top of each wave. The third row is driven in at the centre of each sheet. From 10 to 20 guttanit® TS18 nails are needed to secure each sheet, with polyethylene seal, depending on the windiness of the area. In case of a reinforced concrete slab, on the other hand, fix the sheets using the special hook, using 4 to 6 hooks per sheet, with steel nail.

ROOF SLOPES

For slopes between 15 and 30%, the tiles do not require fixing. In case of reater slopes, the roof tiles must be secured using the stainless steel hooks supplied with the sheets. In any event, it is advisable to use the hooks to secure bent tiles on all roofs.

VENTILATION

To ensure excellent roof ventilation, avoid obstructing the ridge by making sure that the sheets end at least 5 cm from the ridge itself, thus allowing the air to flow through from the eaves, through the grids and up to the rooftop. This constant flow of air avoids the proliferation of mould and mildew, and the formation of condensate.