Does your Brentwood home feel sticky even when the thermostat says 72? You are not imagining it. Middle Tennessee summers bring high dew points that keep indoor air damp, which affects comfort, health, and your home’s finishes. In this guide, you will learn how to control humidity with smart ventilation, whole‑home dehumidifiers, and crawlspace upgrades that work in Brentwood’s hot‑humid climate. Let’s dive in.
Brentwood humidity: why it matters
Brentwood sits in a humid subtropical zone, so summer air carries a lot of moisture. When indoor relative humidity stays high, your body cools less effectively and rooms feel warmer than the thermostat setting. That is why a 72 degree room can still feel clammy in July.
Humidity is more than a comfort issue. Elevated moisture encourages mold and dust mites, which can affect health. It also damages building materials over time. Agencies such as the EPA and CDC recommend keeping indoor humidity in a range that limits biological growth, and many guidelines point to a target around 40 to 50 percent when feasible.
High indoor humidity also strains HVAC systems. Your air conditioner must remove both heat and moisture. If your system is sized or controlled mainly for temperature, it may hit the setpoint but leave the air damp.
Smart ventilation for hot‑humid days
You need fresh air to dilute pollutants, but in Brentwood, outdoor air often arrives with lots of moisture. The key is to ventilate on your terms and pair it with moisture control.
Use spot fans first
- Run bathroom fans during showers and for 10 to 20 minutes after. Make sure they vent outdoors, not into the attic or crawlspace.
- Use a range hood when cooking and after you finish. Capture steam right at the source.
- Replace noisy, weak fans with properly sized, quiet models so you actually use them.
Whole‑house ventilation options
If you install whole‑house ventilation, follow ASHRAE 62.2 for minimum airflow. The standard formula for continuous ventilation is:
- qfan = 0.03 × floor area (ft²) + 7.5 × (number of bedrooms + 1) cfm
There are several system types:
- Supply‑only: Brings in outdoor air and lets it exit through leaks or fans. It can pressurize the house and add moisture in summer.
- Exhaust‑only: Pulls indoor air out and draws outdoor air in through leaks. It can pull humid air through the building shell.
- Balanced systems: Provide controlled supply and exhaust. Two common types are:
- HRV: Transfers heat but little moisture. Better for cold or dry climates.
- ERV: Transfers heat and some moisture. In hot‑humid climates like Brentwood, an ERV often reduces the moisture that enters with outdoor air compared with a simple intake.
Work with a qualified contractor to select and commission a system based on your home and occupancy.
When to pause outdoor air
During heat waves or very humid afternoons, bringing in unconditioned outdoor air can spike indoor humidity. Favor balanced mechanical ventilation with heat and moisture recovery, or shift schedules to cooler times when the AC is running and can help dehumidify.
Smarter controls
- Use timers and humidity controls to avoid running ventilation when it would raise indoor RH above your target.
- Consider demand controls tied to pollutants or occupancy with safeguards that prevent high humidity events.
- Do not run a continuous outdoor air intake if your home lacks adequate dehumidification.
Whole‑home dehumidifiers that work
When ventilation and AC alone cannot keep humidity in check, a whole‑home dehumidifier can stabilize comfort across the house.
Whole‑home vs portable units
Portable dehumidifiers help in a single room or basement but struggle to keep a whole house in range. Whole‑home dehumidifiers connect to your ductwork to treat all living areas, and they drain automatically instead of filling a bucket.
Selecting and sizing
Most residential whole‑home units are refrigerant dehumidifiers that condense water from warm, humid air. Look for AHRI‑listed performance so you can compare models reliably. Capacity is rated in pints per day and should reflect square footage, air leakage, and Brentwood’s high summer moisture loads.
Target a setpoint around 45 percent RH, with a 40 to 50 percent range for balance. Work with a contractor for a load assessment. Sizing only by square footage can miss real‑world factors like occupancy, ventilation rate, and envelope tightness.
Integration and controls
Install the dehumidifier with proper drainage to a condensate line or pump. Many units tie into the return plenum or use dedicated ducts. Control options include a standalone humidistat or integration with the HVAC thermostat. The best setups allow the dehumidifier to run without excessive cooling, which is useful during spring and fall when you still need moisture control.
Energy and comfort benefits
Dehumidifiers add electrical load, but they often let you raise the thermostat a couple of degrees while feeling just as comfortable. They also reduce mold risk and protect finishes. If your issue is moisture rather than temperature, a whole‑home dehumidifier usually performs better than upsizing your AC.
Maintenance
Plan an annual checkup. Clean coils and drains, replace filters, and confirm controls and electrical connections. Proper maintenance keeps efficiency and performance high.
Crawlspace fixes for Brentwood homes
Crawlspaces are a major humidity source in Middle Tennessee. Traditional vented crawlspaces often make things worse by pulling in humid outdoor air. A sealed, well‑detailed approach is the current best practice.
Encapsulated vs vented
Modern guidance from building science experts and energy programs supports encapsulating crawlspaces in humid climates. Encapsulation typically includes:
- A continuous ground vapor barrier, typically 6 mil or thicker polyethylene sealed at seams and run up foundation walls.
- Sealed foundation vents and air sealing to the outdoors.
- Insulated foundation walls where appropriate.
- Drainage improvements if groundwater intrudes.
- Provision for conditioning or dehumidifying the crawlspace.
Benefits include lower indoor humidity, fewer musty odors, better HVAC efficiency, and improved durability. The work must be done correctly to avoid trapping moisture or creating combustion safety issues.
Crawlspace checklist
- Improve site drainage so water moves away from the foundation. Check gutters and downspouts.
- Install and seal a continuous vapor barrier over soil and up the walls.
- Permanently seal crawlspace vents per local code.
- Insulate foundation walls with appropriate materials.
- Fix plumbing leaks and address groundwater before sealing.
- Add a dedicated crawlspace dehumidifier if needed and route the condensate safely.
- Measure crawlspace RH seasonally. Keep the living space target near 45 to 50 percent and the crawlspace below about 60 percent.
Safety and codes
If you have fuel‑burning appliances near or in the crawlspace, a qualified contractor must confirm combustion safety and code compliance after encapsulation. Check with the City of Brentwood or Williamson County building department for any permits required for mechanical changes or drainage work.
A practical roadmap for Brentwood homeowners
Quick wins this week
- Run bathroom and kitchen fans during and after use. Confirm they vent outdoors.
- Set a whole‑home or portable humidistat target near 45 percent RH. Use a reliable hygrometer to spot check.
- Inspect the crawlspace for standing water, musty odors, or damp insulation. If you see issues, pause storage use and call a pro.
- Change HVAC filters and schedule annual service. A clean coil dehumidifies better.
- Seal obvious air leaks around doors, windows, and service penetrations.
High‑impact upgrades
- Install a properly sized whole‑home dehumidifier that can operate independently of cooling.
- Add or upgrade to a balanced ventilation system, often an ERV, if you plan continuous whole‑house ventilation.
- Encapsulate the crawlspace with a continuous vapor barrier, sealed vents, wall insulation, and drainage improvements. Add a crawlspace dehumidifier if needed.
When to call a pro
- Visible mold across large areas or recurring condensation on windows and walls.
- Persistent musty odors or health symptoms linked to time at home.
- Standing water or groundwater intrusion in the crawlspace.
- Plans to add an ERV, whole‑home dehumidifier, or encapsulate the crawlspace. Ask for load calculations, AHRI‑rated equipment, and references.
Local programs and resources
- Check with Williamson County and the City of Brentwood about permits for HVAC changes or crawlspace work.
- Explore local energy programs, such as TVA EnergyRight, for potential rebates, audits, or contractor lists.
- University extension and county health departments can offer moisture and mold prevention education.
Costs and timelines
- Crawlspace encapsulation costs vary widely by size, drainage, and remediation needs. Get multiple bids.
- Whole‑home dehumidifier costs depend on capacity and install complexity. Request AHRI performance documentation.
- ERV installation cost depends on equipment and duct modifications. Consider lifecycle comfort and energy benefits.
Ready to make a plan?
If you are buying, selling, or simply improving a Brentwood home, the right humidity strategy protects comfort, health, and value. From spot fans and smart controls to ERVs, whole‑home dehumidifiers, and encapsulated crawlspaces, you can sequence upgrades to fit your budget and timing. If you want local vendor referrals or help prioritizing projects that influence resale, reach out to The Phillips Group. Our team coordinates trusted inspectors and contractors so you can move forward with confidence.
FAQs
What indoor humidity should Brentwood homeowners target?
- Aim for roughly 40 to 50 percent relative humidity to balance comfort and mold prevention.
Should I open windows in summer to ventilate?
- Generally avoid opening windows during hot, humid periods. Use spot fans and consider balanced mechanical ventilation, ideally with an ERV, or ventilate when the AC can help dehumidify.
Is a whole‑home dehumidifier better than a bigger AC?
- If the main issue is moisture, a whole‑home dehumidifier is usually more effective and efficient than oversizing your air conditioner.
Are vented crawlspaces okay in Brentwood?
- In hot‑humid climates, sealed and conditioned or dehumidified crawlspaces are typically recommended over vented ones, provided drainage and safety details are done correctly.
How do I calculate whole‑house ventilation needs?
- ASHRAE 62.2 provides a baseline: qfan = 0.03 × floor area (ft²) + 7.5 × (number of bedrooms + 1) cfm. A contractor can refine this for your home and climate.
