Ductwork and Indoor Air Quality Guide: Denver

Overview

Ductwork is the hidden half of a forced-air system. Supply ducts carry conditioned air to rooms and return ducts bring it back to the equipment. When ducts leak, are undersized, are poorly balanced or run through unconditioned attics and crawl spaces without insulation, rooms can be uncomfortable even when the furnace or air conditioner is working well.

Common duct problems include disconnected sections, crushed flex duct, leaky joints, too few returns and rooms at the end of long runs that never get enough air. Contractors can measure airflow and static pressure to diagnose these issues, and can test duct leakage with specialized equipment. Fixes range from sealing joints with mastic or approved tape to adding returns or redesigning sections.

Indoor air quality covers filtration, humidity and ventilation. Options include higher-efficiency filters, media filter cabinets, humidifiers for dry climates, dehumidifiers for humid ones and ventilation systems such as ERVs or HRVs that bring in fresh air while recovering energy. Each comes with trade-offs, and the right combination depends on the home and household's needs.

What the work usually involves

Asking about comfort problems, dust, allergies, humidity and odors.
Inspecting accessible ductwork for disconnections, damage and missing insulation.
Measuring static pressure and airflow, where the contractor offers it.
Testing duct leakage if a leakage test is part of the service.
Sealing, repairing, insulating or redesigning duct sections.

Things worth considering

Comfort issues may not be duct-related. Windows, insulation and air sealing also play a role.
Duct cleaning and duct sealing are different. Cleaning removes debris; sealing reduces air leakage. Ask which one addresses your problem.
Air purifiers vary widely. Ask how a device works and what independent testing supports its claims.
Ventilation matters in tight homes. Well-sealed houses may benefit from mechanical ventilation.
Humidifiers need maintenance. Whole-house humidifiers should be cleaned and checked regularly.

Local notes for Denver

At higher elevations, thinner air affects combustion and airflow, and gas furnaces are often derated or configured for altitude according to manufacturer instructions. Ask whether equipment is set up for your elevation.

Colorado's dry climate means many households consider humidification in winter, while summer cooling loads can be significant on hot, sunny days. Large day-to-night temperature swings are also common.

We take inquiries from Denver, Aurora, Lakewood, Littleton, Arvada, Westminster.

Before you send an inquiry

List times you can be reached and when someone can provide access.
If you smell gas or suspect carbon monoxide, leave the home and contact your gas utility or emergency services first, before sending any inquiry.
Share the approximate square footage of the home and how many levels it has, especially for replacement quotes.
Note any rooms that are consistently too hot or too cold, which can point to duct or zoning issues.
Note the make, model and approximate age of your furnace, air conditioner or heat pump. The label is usually on the side of the unit or inside a panel.

Red flags to watch for

Reluctance to show license or insurance information.
No written proposal that lists the equipment model numbers, scope of work and permit responsibility.
Claims that equipment is dangerous without explaining the specific problem or showing you what was found.
Quotes that leave out duct, electrical or venting changes that the new equipment will clearly need.
A replacement recommendation without a load calculation or any measurement of the home.

Questions to ask a provider

How will you determine whether my ducts are the cause of the comfort issue?
Do you test static pressure or duct leakage?
Do you recommend sealing, cleaning, redesign, or a combination?
Which filter rating is appropriate for my equipment?
Would a humidifier, dehumidifier or ventilation system help my home?

Quick answers

Do I need a humidifier?: In dry climates, some households add a whole-house humidifier for comfort. The right humidity level depends on outdoor temperatures and the home's construction.
Why is one room always hotter or colder?: Causes include duct leaks, undersized runs, missing returns, poor balancing, insulation and window differences. A contractor can measure airflow to narrow it down.
Is duct cleaning necessary?: It can help after construction, pest problems or visible contamination, but routine duct cleaning isn't always needed. Ask what problem it's meant to solve.

Ductwork and Indoor Air Quality in Denver