FAQ

Here you will find the most frequently asked questions and answers 24 hours a day, 7 days a week. However, the technical issues may be different for each project. So if your roof is complex, we recommend that you contact our technical department. They will be happy to help you.

When the VAEFUSION S has completely evaporated, you can still touch up the seam with warm air.

The entire roof can be welded with hot air, both the details and the flat overlaps.

With VAEFUSION S, only the flat welds can be made, and that after the details have been made with hot air.

For correct processing, it is best to follow a training course and/or contact our Technical Department.

The minimum ambient temperature for hot air is +5°C.

For VAEFUSION S, this is +10°C. The maximum temperature for VAEFUSION S is 30°C.

Extremely cold weather is first and foremost a problem for the liquid accessories, such as glue, solvent, …. These do not react or react too slowly at low temperatures or are not liquid enough and therefore more difficult to apply.

The VAEPLAN roofing membrane can be installed, but will be more rigid due to the cold temperatures and therefore more difficult to install flat without undulations.

To improve the flatness, the foil can be heated with a flame. The necessary safety measures for working with an open flame must be observed. In colder climates, the rolls can be stored in a heated container on the roof.

In order to weld the seams, the overlap can be pre-heated with the hot-air apparatus, just before the final weld is made.

The method of installation depends on the entire roof structure and possibly on the purpose of the building. Our Technical Department can advise you on this choice.

VAEPLAN is applied in a single layer system. A bituminous underlayer on top of the insulation can be a practical solution as a quick protection of the insulation in less favourable climatic conditions, but it will cancel out the advantage of vapour permeability of VAEPLAN.

In case of increased risk of mechanical or chemical damage, a second layer can be applied locally.

At the start of the installation a small weld test is carried out on a piece of VAEPLAN. By peeling off this weld, you should get a break in the thickness of the VAEPLAN. When you peel off the two strips of VAEPLAN without damage, the settings have to be adjusted (Temperature – Speed – Pressure).

On carried out work you go with a hook or control needle along each joint and try to get under the overlap with light pressure. If this does not work, the weld is good. If it does work in certain places, then pull the overlap loose without damaging the foil, and touch up the weld with hot air.

No, you cannot. Only the flat welds can be carried out with VAEFUSION S. Wherever VAEPLAN has to be deformed, i.e. at the start of a seam, T-seam or corner detail, hot air is required.

In theory this would be perfectly possible, and up until the 1990s this was actually done, but with today’s knowledge this is no longer done. Reinforced roofing membranes with polyester fabric or self-adhesive strips are a much more durable solution.

No problem at all. VAEPLAN consists of one full layer over the whole thickness, therefore it has the same properties on top as on the bottom.

It is allowed to carry out the upstands in VAEPLAN F, but as for the roof surface, for the upstands the preference goes to a reinforced membrane, and in particular to the self-adhesive membrane VAEPLAN VS.

This results in a tighter finish.

The VAELIST profile is aligned according to the VAEPLAN welds. In order to fix the VAELIST profile in a straight line, it is pointed every 10 to 15cm with the manual welding device. In the case of flat or convex roofs, VAELIQUID is then applied under the two side edges of the profile. In the case of hollow roofs, the two side edges are completely welded with hot air.

The VAEFIX profile is always welded on the VAEPLAN with hot air.

For the exact positioning of the profile you can contact DERBIGUM’s Technical Service.

This is perfectly possible. After placing the foil on the curb, a connection profile in VAEPLAN coated steel sheet is attached together with the aluminium profile. With a punched tape in VAEPLAN F the connection between curb film and connection profile is made.

This is perfectly possible. After placing the foil on the curb, the aluminium base profile is fixed. Then the connection between the curb film and the click profile is made with a VAEPLAN F punched strip.

The drains are provided with a strip of homogeneous VAEPLAN F so that they can be directly welded onto the surrounding VAEPLAN. With VAEPLAN a counter seam is not a problem because the seams are homogeneously welded.

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