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18x18x18 Insulated Ductboard Elbow R4.2 HVAC Flex Triangle

SKU: 18X18X18 TRIANGLE

$127.98

Only 2 left in stock

Same-item volume pricing
QuantityUnit priceSaving
1–4$127.980%
5–9$121.585%
10+$115.1810%

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Available to order: 2.

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18x18x18 Insulated Ductboard Elbow – R4.2 – HVAC Foil Faced

This 18″ x 18″ x 18″ insulated ductboard triangle section is designed for HVAC air distribution systems where insulated elbows or plenum transitions are required. Pre-fabricated for faster installation, this component reduces field labor while maintaining thermal efficiency.

Constructed from fiberglass ductboard with a foil vapor barrier facing, this section provides R4.2 insulation value to help reduce heat loss, condensation, and energy waste.


Key Benefits:

✔ R4.2 thermal insulation

✔ Pre-fabricated elbow/triangle section

✔ Foil-faced vapor barrier

✔ Lightweight and easy to install

✔ Ideal for supply or return duct systems


Common Applications:

  • Furnace supply trunk transitions

  • Air handler elbow sections

  • Ductboard plenum construction

  • Energy-efficient residential HVAC installs

Compatible with:

  • Ductboard systems

  • Foil tape and mastic sealing

  • Standard HVAC trunk lines

Important Notice – Propane Parts, Accessories, and Regulators

This product, including but not limited to propane parts, accessories, fittings, hoses, valves, and regulators, must be installed and serviced by a licensed professional in accordance with all applicable local, state, and federal codes, regulations, and standards.

The seller assumes no responsibility for the installation, inspection, application, maintenance, or use of this product.

It is the sole responsibility of the buyer to ensure the product is appropriate for their intended application and that it is installed correctly by a qualified individual.

Improper installation, maintenance, or use of propane products may result in serious injury, death, fire, explosion, or property damage.

The buyer accepts all risks, liabilities, and potential consequences associated with the use of this product.

By purchasing this item, the buyer acknowledges that they have read, understood, and agreed to these terms and confirm that installation and use will be conducted by a properly licensed and qualified professional.

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