How to Make an Old Home More Energy Efficient

Older homes have character and charm, but they often lack modern energy efficiency. In Tucson's climate, an inefficient older home can mean sky-high utility bills and inconsistent comfort. Here's how to upgrade your older home for better efficiency without losing its character.

Start with an Energy Audit

Before making improvements, understand where energy is being wasted.

Professional Energy Audit

A professional audit identifies specific problems:

• Thermal imaging reveals heat gain/loss areas
• Blower door tests find air leaks
• Duct testing measures leakage
• Equipment efficiency evaluation
• Prioritized recommendations

Many utility companies offer free or subsidized audits.

DIY Assessment

You can identify some issues yourself:

• Check for drafts around windows and doors
• Inspect visible insulation in attic
• Look for gaps around pipes and wires
• Note which rooms are hardest to cool

Priority Upgrades for Tucson Homes

1. Attic Insulation

In Arizona, heat gain through the roof is a major issue.

Current insulation check:

• Less than 6 inches of insulation: Definitely add more
• 6-10 inches: Consider upgrading
• 12+ inches (R-38 or higher): Probably adequate

Recommended levels:

• Minimum: R-38 (about 10-14 inches of fiberglass)
• Ideal: R-49 or higher for maximum benefit

Cost and savings:

• Investment: $1,500-3,500 for average home
• Savings: 10-25% on cooling costs
• Payback: 2-5 years

2. Air Sealing

Air leaks waste enormous amounts of energy.

Common leak locations:

• Around windows and doors
• Where pipes and wires enter walls
• Recessed lights in ceilings
• Attic access panels
• Electrical outlets on exterior walls

Solutions:

• Caulk gaps around windows and frames
• Weatherstrip doors
• Use foam sealant around penetrations
• Install gaskets behind outlet covers

3. Window Improvements

Old single-pane windows are energy disasters in Arizona.

Options from least to most expensive:

1. Window film: Reflects heat, $50-200 DIY
2. Cellular shades: Insulating value, $100-500 per window
3. Storm windows: Add insulating layer, $150-400 per window
4. Replacement windows: Best performance, $500-1,500 per window

For older homes, low-E coating and dual-pane glass dramatically reduce heat gain.

4. HVAC System Upgrade

Older AC systems are far less efficient than modern units.

Efficiency comparison:

• 20-year-old system: 8-10 SEER
• Modern standard: 14-16 SEER
• High-efficiency: 18-25+ SEER

Upgrade benefits:

• 25-50% reduction in cooling costs
• Better humidity control
• Quieter operation
• Improved reliability

5. Duct Sealing and Insulation

Duct problems are common in older homes.

Issues to address:

• Leaks at connections and joints
• Inadequate or missing insulation
• Ducts in unconditioned spaces (attics)

Solutions:

• Professional duct sealing: $500-1,500
• Adding duct insulation: $300-800
• Potential savings: 10-30% on cooling

6. Smart Thermostat Installation

Older thermostats lack programmable features.

Benefits of smart thermostats:

• Learning your schedule
• Remote control via phone
• Energy usage tracking
• Automatic adjustments
• Typically 10-15% savings

Cost:

• Device: $150-300
• Professional installation: $50-100

Additional Improvements

Exterior Shading

Blocking heat before it reaches windows is highly effective:

• Shade trees (long-term investment)
• Awnings over windows
• Solar screens
• Exterior shutters

Cool Roof Coating

Reflective roof coatings reduce heat absorption:

• Reflects solar radiation
• Reduces attic temperatures by 20-30°F
• Extends roof life
• Cost: $2-4 per square foot

LED Lighting

Replace incandescent and CFL bulbs with LEDs:

• 75% less electricity
• 25x longer life
• Much less heat output (helps cooling)
• Immediate payback

Efficient Water Heating

Water heating is the second-largest energy expense:

• Insulate water heater and pipes
• Lower temperature to 120°F
• Consider solar water heating
• Upgrade to heat pump water heater

Prioritizing Improvements

Not all upgrades offer the same return. Here's a general priority order for Tucson homes:

1. Air sealing - Low cost, high impact
2. Attic insulation - Excellent payback
3. Duct sealing - Often overlooked but important
4. HVAC upgrade - If system is 15+ years old
5. Window improvements - Start with film or shades
6. Smart thermostat - Quick, affordable improvement

Incentives and Rebates

Take advantage of available incentives:

• Federal tax credits for energy improvements
• Utility company rebates
• Arizona state incentives
• Manufacturer rebates

Check DSIRE database and your utility's website for current programs.

Professional Help

Some improvements require professional expertise:

• HVAC system replacement
• Electrical upgrades
• Major insulation projects
• Duct system work

Intelligent Design offers comprehensive home efficiency services including HVAC, electrical, and solar. Call (520) 333-2665 for an assessment of your older home's energy efficiency opportunities.