Double membrane air domes look simple from the outside. A round, inflated structure standing tall without any pillars or beams. But what makes this structure work is not the shape. It is the fabric.

The fabric used in air domes has to do a tough job. It holds air pressure inside the structure. It stands up to sun, rain, and wind. And it does this for years without tearing or losing shape. In this blog, we will look closely at this fabric, what it is made of, and why it matters so much for double membrane air domes.

What Is a Double Membrane Air Dome?

A double membrane air dome is a structure made of two layers of coated fabric. Air is pumped between these two layers. This air keeps the dome standing and gives it its round shape. There is no metal frame inside. The air pressure itself becomes the support system.

This design is used for sports halls, warehouses, storage covers, and other large open spaces. It is popular because it can cover a big area without using pillars in the middle. That gives full open space inside.

But this design only works if the fabric is right. A weak fabric will not hold air pressure properly. It may stretch, leak, or tear under load. So the fabric is really the heart of the whole structure.

What Is the Fabric Made Of?

The fabric used for double membrane air domes is a coated fabric. It is not plain cloth. It has two main parts:

Base fabric This is the woven layer inside. It is usually made of polyester yarn. This layer gives the fabric its strength. It is what holds the fabric together and stops it from tearing.

Coating On top of the base fabric, a coating is applied on both sides. This coating is usually PVC (Polyvinyl Chloride) or PVDF (Polyvinylidene Fluoride). The coating protects the base fabric from water, UV rays, and weather. It also makes the fabric airtight, which is very important for air domes since they depend on trapped air pressure.

PVC coated fabric is widely used because it is flexible, cost effective, and performs well in most climates. PVDF coated fabric adds an extra top layer that improves resistance to dirt, staining, and UV exposure, keeping the surface cleaner for longer.

Why the Fabric Needs to Be Airtight

An air dome only stands because of internal air pressure. If the fabric has even small leaks, the dome will slowly lose pressure and sag. This is why the coating on the fabric is so important. It seals the woven base layer completely, so air stays trapped between the two membrane layers.

Airtightness is not something that can be fixed after the fabric is made. It has to be built into the fabric from the start, through proper coating and correct weld joints when the panels are joined together.

Flexibility Without Losing Strength

A dome fabric needs to bend and flex constantly. Wind pushes against it. Air pressure inside pushes outward. The fabric moves with these forces instead of resisting them stiffly. If the fabric was rigid, it would crack or damage under this constant movement.

This is why coated fabric works so well for air domes. The base fabric layer gives strength, so it does not stretch out of shape. The coating gives flexibility, so it can move without cracking. Together, they create a material that can flex daily for years while still holding its form.

Weather Resistance

Air domes are usually installed outdoors, so the fabric faces sun, rain, wind, and sometimes snow load, all year round.

PVC and PVDF coatings are chosen because they resist:

• UV rays from constant sun exposure
• Rainwater and moisture without soaking through
• Temperature changes across seasons
• Wind load pressing against the dome surface

This weather resistance protects not just the fabric, but everything inside the dome as well.

Why the Fabric Quality Matters So Much

Since the entire dome structure depends on the fabric, the quality of this fabric decides how well the dome performs. A well-made coated fabric keeps its airtightness, holds its strength, and resists weather damage properly.

This is also why the fabric supply chain matters. Good quality PVC and PVDF coated fabric requires precise coating thickness, strong adhesion between the base layer and coating, and consistent quality across every roll. This is a specialised manufacturing process, not something that can be done casually.

Why Choose Biodomes

When it comes to sourcing PVC and PVDF coated fabric for air domes, Biodomes Membranes India focuses on getting the fabric fundamentals right.

Fabric-first approach Biodomes works specifically with PVC and PVDF coated fabric, so the focus stays on getting the coating, strength, and airtightness of the material correct.

Consistent quality Every roll of fabric is meant to perform the same way, so dome builders can rely on it panel after panel, without surprises.

Built for outdoor use The fabric is designed to handle sun, rain, and wind, so the dome stays strong across changing seasons.

Support for dome projects Whether it's a new air dome project or fabric replacement for an existing structure, Biodomes supplies the coated fabric needed for the job.

FAQs

1. What fabric is used in double membrane air domes?

PVC or PVDF coated polyester fabric is used. It has a woven base layer for strength and a coating for airtightness and weather resistance.

2. What is the difference between PVC and PVDF coated fabric?

PVC coated fabric is flexible and cost effective. PVDF coated fabric has an extra top layer that resists staining and UV exposure better, keeping the surface cleaner over time.

3. Why does the fabric need to be airtight?

Because the dome stands due to air pressure trapped between the two membrane layers. Any leak in the fabric can cause the dome to lose shape.

4. How long does dome fabric usually last?

It depends on climate, usage, and maintenance, but good quality coated fabric is built to handle long-term outdoor exposure.

5. Can old air dome fabric be replaced?

Yes, if a dome's fabric is worn out or damaged, it can be replaced with new coated fabric without needing to rebuild the whole structure.