The durability of this material is approximately 15-20yrs. Some of the roofs have exceeded the durability of 20 yrs. without any damages. There are many examples of roofs fulfilling their function since the early 70s without any necessary maintenance or repair.

Due to the very good material properties, a project bound guarantee up to 10yrs. can be granted.

This material corresponds to the fire class B1 according to DIN 4102 and is therefore graded flame retardant. The material can be considered self extinguishing when direct flame is removed.

In contrast to conventional roofs the maintenance intensity of this material is very low. Due to the low adhesion of dirt on PVC any pollution is mainly removed by rain. This material needs to be cleaned down annually as a minimum to maintain the fabric manufacturers warranty. No aggressive or environment-polluting detergents need to be used.

The translucency of this fabric depends on the necessary thickness of material. The translucency is approximately between 5% and 15%. Please note that the translucency of 5% for the white roof still provides enough light for reading a newspaper beneath.

PVC is available in a variety of colors.

What is the life expectancy?
Permanent Structures: 10-20 years depending on pollution
Reported Experience: 15-25 years

What happenes to the material when in use?
After some years, plasticisers begin to migrate. The material becomes less flexible. A slight change of color is possible.

What sort of warranty do you give?
Permanent structures only: 10 years for MEHATOP F, PVD top coat,
5 years for MEHATOP A, acrylic top coat.

At the end of the warranty period, the strength will not be less than 70% of the original strength. Membrane will stay flame retardant and water tight.

What is the uv stablility like?
Quite good. UV-inhibitors absorb the UV rays and protect the other pigments from fading. Depending on the intensity of the UV radiation.

Are there other colors than white?
Yes, in the range of tent materials there are 10 different standard shades available. Colors of heavier types on request.

What is the color fastness like?
Color fastness is rated as grade 6 out of 7, which means quite good to excellent.

What is the light translucency like?
Standard white 3-7%, depending on the strength-type/thickness. Higher translucency available upon request. (e.g 15% for type II). Flame-retardant liner available with 45-505 translucency, measured at 550nm. Opaque(block out) versions are available as well.

Is the material flame retardent?
Yes, the material meets most common specifications concerning combustibility, e.g California Fire Marshall, British Standard 7837, German DIN 4102, French M2. Certificates on request.

How do you make a seam?
The most effective and most controlled way of joining is "high frequency welding". Adjust the width of the seam to the strength-type/thickness of the material.

How strong is the seam?
At room temperature: 90% of the fabric strength
At elevated temperature: (=70'C): 60% of the fabric strength (Adjust the width of the seam to the type/thickness of the material)

What are the limitaions of PES/PVC?
Light Translucency is less than glass. PES/PVC have lower fire test rating than mineral based materials. Despite using anti-mildew additives, PED?PVD can be attacked by microbes if pollution is hot and very humid.

What are the advantages of PES/PVC?
Very flexible, easy to fabricate, easy to handle, light weight, lower cost.

If PES/PVC - why Valmex?
Because

	various widths quickly available
	global proven architectural experience for a long time
	a wide range of classified strength values
	easy weldable top coats: MEHATOP A = acrylic lacquer; MEHATOP F = PVDF lacquer