The primary difference between lumber tarps and steel tarps lies in their design, size, and intended use. While both are used to protect cargo during transportation on flatbed trucks, they cater to different types of loads—lumber (typically taller and more irregular) versus steel (typically lower, more compact).

Here are the main distinctions between lumber tarps and steel tarps:

  1. Size and Dimensions

Lumber Tarps:

Larger in size, usually around 24–28 feet long and 20–28 feet wide.

Designed to cover taller loads of lumber that may be stacked high on a flatbed truck. The extra width and length allow the tarp to drape fully over the cargo and cover the sides.

Many lumber tarps feature end flaps that provide additional coverage for the front and back of the load, especially for uneven or irregular shapes.

Steel Tarps:

Smaller and more compact, typically around 16–20 feet long and 10–16 feet wide.

Designed to cover lower, more compact loads like steel sheets, pipes, or other flat or cylindrical cargo. Steel loads usually don’t require the same height coverage as lumber.

Steel tarps do not usually have end flaps, as steel loads tend to be more uniform and lower to the ground.

  1. Design and Shape

Lumber Tarps:

Feature side and rear flaps to cover the entire height and ends of the load. This ensures complete protection of taller, bulkier cargo from rain, snow, and debris.

Often come with additional D-rings and grommets along the edges and flaps for securing them tightly, especially given the irregular shape of lumber loads.

 

Steel Tarps:

No flaps or only minimal side coverage. Steel tarps are rectangular and flat, focusing on providing coverage for low-profile loads that don’t need the extra material to cover large side areas.

Typically lighter than lumber tarps due to less material being required, making them easier to handle for drivers.

  1. Weight and Handling

Lumber Tarps:

Heavier and bulkier due to their larger size and extra flaps.

Can weigh 60–120 pounds, depending on material and dimensions, making them more challenging to handle.

Require more time to secure properly because of their size and extra tie-down points.

Steel Tarps:

Lighter and easier to handle since they are smaller and don’t have the large end or side flaps.

Typically weigh around 40–70 pounds, making them quicker and more efficient to deploy and secure over low-profile loads like steel or machinery.

  1. Intended Use

Lumber Tarps:

Primarily used for transporting lumber or other tall and irregularly shaped loads that require full coverage from top to bottom.

Also used to cover other materials like insulation or equipment that might be stacked high or exposed to the elements.

Steel Tarps:

Specifically designed for transporting steel or other flat, low-profile cargo like pipes or sheets of metal.

Ideal for protecting cargo that doesn’t require coverage for height or unusual shapes, focusing more on surface protection from rain, dust, and road debris.

  1. Material and Durability

Both lumber and steel tarps are typically made from durable, PVC-coated vinyl material that is waterproof and UV-resistant. However:

Lumber Tarps may have heavier material to provide better durability against elements like wind and to withstand the strain of covering larger, irregular loads.

Steel Tarps are usually slightly lighter because they don’t need to cover as large or tall a load, though they still provide strong protection against rain, rust, and road debris.

Summary of Differences

Feature Lumber Tarps Steel Tarps
Size Larger (24-28 feet long, 20-28 feet wide) Smaller (16-20 feet long, 10-16 feet wide)
Shape Includes flaps to cover high stacks Rectangular with no flaps
Weight Heavier (60-120 pounds) Lighter (40-70 pounds)
Usage Tall/irregular loads like lumber Low-profile loads like steel sheets
Durability Made to handle taller and bulkier cargo Focused on surface protection

In essence, lumber tarps are larger and heavier, designed to protect tall and irregularly shaped cargo like stacked lumber, while steel tarps are smaller, lighter, and ideal for low-profile, more uniform loads like steel sheets.

GSM (Grams per Square Meter) and OZ (Ounces per Square Yard) are two units used to measure the weight and thickness of tarps, helping to determine their durability and strength.

 

GSM (Grams per Square Meter)

GSM measures the weight of the tarp material per square meter of fabric.

The higher the GSM, the thicker and heavier the tarp, meaning it will generally be more durable and better at withstanding harsh weather conditions.

OZ (Ounces per Square Yard)

OZ measures the weight of the tarp material per square yard of fabric.

Like GSM, the higher the OZ, the thicker and stronger the tarp will be.

How to Convert OZ to GSM

To convert ounces per square yard (oz/yd²) to grams per square meter (GSM), you can use this formula:

GSM=OZ×33.906

Conversion Example

If a tarp has a weight of 10 oz/yd², you can calculate its GSM as follows:

GSM=10×33.906=339.06GSM

This means a 10 oz/yd² tarp weighs approximately 339 GSM.

Why Convert Between GSM and OZ?

GSM is more commonly used in European and Asian markets, while OZ is more common in the USA and Canada Converting between the two allows you to compare tarp specifications easily, no matter where you’re buying from.

In short:

GSM: Grams per Square Meter (used more globally).

OZ: Ounces per Square Yard (used mainly in the U.S.).

By understanding both units, you can select the right tarp based on the region and ensure you get the right weight and thickness for your project.

GSM stands for Grams per Square Meter and is a unit of measurement used to describe the weight and thickness of a material, in this case, tarps. GSM indicates the density of the tarp fabric, with higher GSM values representing thicker, heavier, and typically more durable tarps. Lower GSM values correspond to lighter, thinner tarps. Knowing the GSM of a tarp helps in selecting the right tarp for different applications based on the strength and durability needed.

What GSM Means for Tarps?

Lower GSM (100-200 GSM): These tarps are lighter and more flexible. They are often used for lighter-duty applications, such as temporary covers, camping, or protecting items from light rain.

Medium GSM (200-350 GSM): These are medium-duty tarps and are suitable for general purposes, including construction sites, gardening, and short-term outdoor storage.

Higher GSM (350-700 GSM and above): These are heavy-duty tarps that provide superior durability and protection. They are used for industrial purposes, long-term outdoor exposure, transportation, and covering large or sensitive items like machinery, lumber, or vehicles.

How to Measure the GSM of a Tarp?

To calculate the GSM of a tarp, follow these steps:

  1. Weigh a Known Area of the Tarp

Cut a small, measured section of the tarp, typically 1 square meter (or a known size, e.g., 1 square foot, and convert to square meters).

Weigh that section using a digital scale that provides the measurement in grams.

  1. Calculate the GSM

If you already measured a 1-square-meter section, the weight in grams is the GSM.

If you measured a different area (e.g., 0.5 square meters or 0.25 square meters), multiply the weight to reflect a full square meter. Here’s the formula:

GSM= Area of the tarp section (in square meters)÷Weight of the tarp section (in grams)

For example:

If you weigh a 0.5 square meter section and it weighs 200 grams, you would calculate the GSM as:

GSM=200÷0.5=400GSM

Why GSM Matters?

Durability: Higher GSM tarps are more durable and better suited for long-term or heavy-duty use.

Water Resistance: Heavier tarps (higher GSM) generally offer better water resistance, making them suitable for rain, snow, or extreme weather.

Application: Choosing the correct GSM helps ensure that the tarp will hold up to the required task. For example, a tarp with a higher GSM is ideal for covering construction materials or vehicles, while a lower GSM tarp might suffice for lightweight outdoor protection.

Understanding GSM ensures that you select the right tarp for your specific needs based on strength, weather resistance, and durability.