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Ductwork Design: How Bad Ducts Waste Your Money

Discover how ductwork problems cause comfort issues and energy waste—and what can be done about it.

David KimJanuary 14, 20258 min read

The Hidden Impact of Ductwork

Ducts distribute conditioned air throughout your home. Poor ductwork can waste 25-40% of heating and cooling energy—more than any other component.

Common Ductwork Problems

Leaky connections, crushed flex duct, undersized runs, poor insulation, and restrictive turns all reduce system performance significantly.

Signs of Duct Problems

Some rooms too hot or cold. Higher-than-expected energy bills. Excessive dust. Noise from ducts. Poor airflow from registers.

Duct Leakage Testing

Duct blaster tests measure total leakage. Many homes lose 20-30% of airflow through duct leaks. Sealing to under 10% leakage significantly improves efficiency.

Duct Sealing Options

Mastic sealant and metal tape seal accessible leaks. Aerosol duct sealing (Aeroseal) seals from inside, reaching inaccessible areas.

When Duct Replacement Is Needed

Severely damaged, undersized, or poorly designed ductwork may need replacement. This is often done during HVAC replacement for optimal matching.

Frequently Asked Questions

Quick answers to common questions

No. Cleaning removes dust and debris; sealing fixes air leaks. Both may be beneficial, but they address different problems.

Manual sealing with mastic costs $500-$1,500 depending on accessibility. Aeroseal costs $2,000-$4,000 but reaches all leaks.

Related topics:

ductwork designduct problemsduct efficiency

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