Double Wall

Name: Double Wall
Brand: FRP MFG
Price: 199.90 USD
Availability: InStock
Rating: 4.6 (27 reviews)

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FRP/Mocoat is a leading manufacturer of double wall tanks – both above ground and below ground throughout North America. Our projects start with proper engineering design in conjunction with customer specific requirements. Typically, an in-house autocad drawing will be generated for approval and involves a sign off from a professional engineer registered in the province or state that the tank will be put into service.

The interstitial space is composed of a 3D fabric providing for continuous monitoring of the interstitial space while also providing continual laminating support to maximize strength. Each primary tank is tested and the interstitial space is also tested using either a pressure or a vacuum test.

Unlike steel it will not rust or corrode. Unlike concrete it is lightweight and not subject to deterioration.

Click on the link below to watch a video on our double-wall tanks!

Videos – FRP Mocoat Fiberglass Ltd. (frpmfg.com)

Frequently Asked Questions

Are FRP septic tanks approved for use in Washington State?

Yes. Every FRP septic tank we manufacture meets or exceeds CSA Standard B66, a key compliance benchmark for wastewater containment. These tanks are suitable for use across Washington in residential, industrial, and remote applications, where code-compliant, environmentally safe septic solutions are required.

What sizes do your fiberglass septic tanks come in?

We offer a variety of sizes to accommodate different needs – from small-capacity tanks for cabins and tiny homes, to larger systems for full-time residences, work camps, and commercial setups. Our team can help you select the right size based on your expected usage and site conditions.

How long do fiberglass septic tanks last?

With proper installation and maintenance, fiberglass septic tanks can last 40 years or more. Their corrosion resistance and seamless construction help prevent leaks and structural failures, even when buried underground for decades. That’s why many Washington property owners choose fiberglass over concrete or steel.

How does a fiberglass septic tank handle Washington’s wet and coastal regions?

Washington’s coastal zones, like those around Seattle or Bellingham, deal with high groundwater and fluctuating soil conditions. Fiberglass septic tanks are non-corrosive and watertight, making them a great fit for these environments. Their lightweight nature also allows for easier placement without the need for heavy equipment, even in challenging terrain.