How to Fix Energy Inefficiency in Older Homes

Older homes have charm and history, but they often waste a lot of energy. Our own 172-year-old Italianate house is a good example. Even after many upgrades, it still gets drafty in the winter. We’ve had to spend a lot of money on heating and insulation just to keep warm. Many older homes were built before modern energy-saving standards, which means they often have poor insulation, single-pane windows, outdated heating systems, and inefficient lighting. This guide covers the best strategies to improve energy efficiency in old homes, lower utility costs, and create a more comfortable living space based on our experience.

Quick Summary

• Older homes lose heat through gaps, poor insulation, and drafty windows. Sealing these gaps and adding insulation can reduce energy loss by 15% to 20%.
• Replacing outdated heating, cooling, and appliances with high-efficiency models reduces energy waste. 
• Upgrading to double-pane windows and new HVAC systems can lower energy use by 30% to 50%.
• Using LED lighting, smart thermostats, and solar panels can improve comfort and reduce energy bills.

Understanding Energy Efficiency of Old Homes

Most old homes were built long before we understood how to save energy. Back then, fuel was cheap and people didn’t worry about wasting it. As a result, many old homes have serious energy problems that cost homeowners lots of money every month.

Energy efficiency means using less energy to do the same job. For example, an energy-efficient light bulb uses less electricity but gives the same amount of light. When we talk about energy efficiency of old homes, we mean making these houses use less energy for heating, cooling, lighting, and running appliances.

Old homes typically waste energy in several ways. First, they let heated or cooled air escape through cracks and gaps. Second, they don’t have enough insulation to keep the temperature comfortable inside. Third, they often have old systems that use much more energy than newer ones.

How Energy Loss Happens in Older Homes?

Most older homes were built before today’s energy codes. Many have little or no insulation, old single-pane windows, and outdated heating and cooling systems. We can confirm this from personal experience. Despite our efforts, our home still loses a lot of heat.

Common Causes of Energy Waste

Why You Should Do a Home Energy Audit?

Before making improvements, hire a professional to do a home energy audit. While this assessment costs money, it is a good idea to look at any local or state incentive programs that can partially or fully cover it. The audit can identify specific areas where your home loses energy and help you reduce your energy costs and carbon footprint.

During a professional audit, experts will do several tests. They use special tools to find air leaks and missing insulation. They also check your heating and cooling systems to make sure they work safely and efficiently. At the end, you get a detailed report that shows exactly what needs to be fixed.

What a Professional Audit Includes:

1. Blower door tests to find where air is leaking
2. Infrared camera scans to spot missing insulation
3. Check appliance efficiency and safety
4. Combustion tests for heaters and stoves
5. Look over past utility bills to find patterns

If you don’t want to hire someone, you can do a simple check yourself.

While a professional audit provides detailed insights, you can also conduct a simple DIY inspection to reduce draft and make your home more comfortable.

How to Do a DIY Home Energy Audit

1. Check for air leaks: Feel around windows, doors, and electrical outlets for drafts.
2. Inspect insulation: Look in the attic, walls, and basement for gaps or insufficient insulation.
3. Evaluate windows and doors: Check for single-pane glass, broken seals, or deteriorated weatherstripping.
4. Assess heating and cooling systems: Listen for unusual noises, check air filters, and look at energy bills for signs of inefficiency.
5. Examine lighting and appliances: Identify older incandescent bulbs and outdated appliances that consume excess energy.

Sealing Air Leaks and Adding Insulation

One of the most cost-effective ways to reduce heat loss in an old home is by sealing air leaks and adding insulation. The U.S. Environmental Protection Agency (EPA) estimates that homeowners can save an average of 15% on heating and cooling costs by air sealing their homes and adding insulation in attics, floors over crawl spaces, and accessible basement rim joists.

Where to Add Insulation:

1. Attics and roofs
2. Outside walls
3. Basement walls and crawlspaces
4. Around pipes and ducts
5. Floors above unheated spaces

How to Seal Air Leaks in an Old House

Here are some simple ways to seal air leaks in your old home:

• Add weatherstripping to doors and windows – This flexible material fills gaps around movable parts. You can buy foam, felt, or rubber weatherstripping at any hardware store.
• Use caulk to fill gaps and cracks – Caulk is like toothpaste that hardens when it dries. Use it around window frames, where walls meet, and around pipes.
• Seal your ductwork – Leaky ducts waste a lot of energy. Use special duct tape or mastic to seal any gaps or holes in your heating and cooling ducts.
• Install door sweeps – These attach to the bottom of doors to stop air from coming in underneath.
• Add foam gaskets behind electrical outlets – Remove the cover plate and install a foam gasket to stop air leaks.

Best Insulation Options for Old Houses

Different types of insulation work better in different parts of your home. Here are the most common options for improving energy efficiency of old homes:

• Blown-in cellulose is made from recycled paper and works great in old homes. It can be blown into wall cavities without removing the wall covering. This makes it perfect for old homes where you don’t want to tear down walls.
• Spray foam expands when it’s applied, so it fills gaps and cracks while also providing insulation. It costs more than other types, but it’s very effective at stopping air leaks.
• Fiberglass batts are the pink or yellow insulation you see in most hardware stores. They’re easy to install yourself and don’t cost too much. However, they don’t work as well if they’re not installed perfectly.
• Rigid foam boards provide excellent insulation and can be used in places where other types won’t work. They’re often used on basement walls or on the outside of homes.

Upgrading Windows and Doors for Better Energy Efficiency

While replacing all windows in an older home can be expensive ($8,000-20,000 on average), the energy savings can be substantial. According to the National Fenestration Rating Council, high-performance windows, doors, and skylights regulate heat flow, contributing to lower energy costs.

Old windows usually have single panes of glass with very little protection from outside temperatures. Modern windows have two or three panes of glass with special coatings and gas between the panes. This provides much better insulation.

However, you don’t have to replace all your windows at once to improve energy efficiency. There are several less expensive options that can still make a big difference.

Window Improvement Options:

1. Install storm windows: An affordable alternative to full window replacements.
2. Upgrade to double or triple-pane glass: Reduces heat transfer.
3. Apply window films and solar blinds: Helps reflect heat in summer and retain warmth in winter.
4. Use thermal curtains: Adds an extra barrier against heat loss.

Door Improvements

Don’t forget about your doors when improving energy efficiency of old homes. Old doors often have gaps that let in lots of outside air. Here are some ways to improve them:

• Replace old doors with energy-efficient models that have better insulation.
• Add weatherstripping around the door frame to seal gaps.
• Install door sweeps at the bottom to stop air from coming in underneath.
• Use storm doors to add an extra layer of protection.

Modernizing Heating and Cooling Systems

Old heating and cooling systems are often the biggest energy wasters in old homes. A furnace or boiler from the 1980s or 1990s might only be 65% efficient. This means 35% of the fuel you buy is wasted. Modern systems can be over 95% efficient.

Replacing your heating and cooling system is expensive, but it can dramatically improve energy efficiency of old homes. The average cost is $5,000 to $15,000, but you’ll save money on energy bills every month for many years.

When choosing a new system, look for the efficiency ratings. For furnaces, look for Annual Fuel Utilization Efficiency (AFUE) ratings of 90% or higher. For air conditioners and heat pumps, look for high Seasonal Energy Efficiency Ratio (SEER) ratings.

Best HVAC Systems for Old Homes

• High-efficiency furnaces burn fuel much more completely than old ones. They also have better heat exchangers that capture more heat from the burning fuel. This means you get more heat for every dollar you spend on fuel.
• Heat pumps are very efficient because they move heat instead of creating it. They can provide both heating and cooling, which means you only need one system. New cold-climate heat pumps work well even when it’s very cold outside.
• Ductless mini-splits are perfect for old homes that don’t have ductwork. They consist of an outdoor unit connected to indoor units in each room. They’re very efficient and let you control the temperature in each room separately.
• Smart thermostats learn your schedule and adjust the temperature automatically. They can save 10-15% on heating and cooling costs by making sure you’re not heating or cooling your home when nobody’s there.

Improving Your Existing System

If you can’t afford to replace your entire heating and cooling system, there are still ways to improve its efficiency:

• Seal your ductwork – Leaky ducts can waste 20-30% of your heated or cooled air.
• Replace your air filter regularly – A dirty filter makes your system work harder.
• Have your system serviced annually – Regular maintenance keeps it running efficiently.
• Add a programmable thermostat – This lets you automatically adjust temperatures when you’re sleeping or away.

Energy-Efficient Lighting Solutions

Switching to efficient lighting for old houses is a simple, cost-effective way to cut electricity use. LED bulbs use 75% less energy than traditional incandescent bulbs and last 25 times longer. This means you’ll save money on both electricity and replacement bulbs.

The upfront cost of LED bulbs is higher than old-style bulbs, but they pay for themselves quickly. A typical LED bulb costs about $3-5 but can save you $50-100 over its lifetime compared to incandescent bulbs.

Best Energy-Efficient Lighting Options

Here are the best lighting options for old homes:

• LED bulbs – Use 75% less energy than incandescent bulbs and last much longer.
• Smart lighting systems – Let you control lights from your phone and set schedules.
• Motion sensor lights – Turn on only when someone is in the room.
• Dimmer switches – Let you adjust brightness and use less energy.
• Solar-powered outdoor lights – Use the sun’s energy for outdoor lighting.

Water Heating Improvements

Water heating accounts for about 18% of home energy use. Modern water heaters can significantly reduce this consumption. Consider solar water heaters for maximum efficiency.

Water Heating Options:

Here are the main types of efficient water heaters:

1. High-efficiency tank water heaters (Energy Factor > 0.90) – These look like traditional water heaters but use less energy.
2. Tankless water heaters (Energy Factor > 0.95) – These heat water only when you need it.
3. Heat pump water heaters (Energy Factor > 2.0) – These use heat from the air to heat water.
4. Solar water heating systems – These use the sun’s energy to heat water.

Simple Water Heating Improvements

Even if you can’t replace your water heater, you can still make it more efficient:

• Insulate your water heater – Add an insulating blanket to reduce heat loss.
• Insulate hot water pipes – This keeps water hot as it travels to faucets.
• Lower the temperature – Set your water heater to 120°F instead of 140°F.
• Fix leaks – A dripping hot water faucet wastes both water and energy.
• Use low-flow showerheads – These use less hot water without reducing pressure.

Installing Energy-Efficient Appliances

Older appliances consume more power than modern energy-efficient models. Refrigerators, washers, dryers, and dishwashers have all become much more efficient in recent years. Energy-efficient home improvements should include upgrading outdated appliances to ENERGY STAR-rated models.

Appliances That Should Be Upgraded

Exploring Renewable Energy Options

Adding renewable energy options for old homes can further cut energy costs. Solar panels are the most popular option, but there are other renewable energy choices too. Solar panels have become much more affordable in recent years. The cost has dropped by more than 70% since 2010. Federal tax credits and state incentives can reduce the cost even more. In many areas, solar panels can pay for themselves in 8-12 years.

Solar Power and Other Renewable Solutions

• Solar panels: Generates electricity and lowers utility bills.
• Solar water heaters: Uses the sun’s energy to heat water.
• Wind turbines: A good option in windy regions.
• Geothermal heating and cooling: Provides sustainable temperature control.

Consider installing a hybrid solar-wind system or exploring DIY solar panel options. Also, home battery storage systems can help optimize your renewable energy usage. Be sure to follow proper battery storage safety guidelines.

Financial Assistance and Incentives

Upgrading an old home can be costly, but energy rebates and tax credits can offset expenses.

1. Federal tax credits: Available for insulation, HVAC systems, and renewable energy.
2. Utility company rebates: Many utilities offer incentives for efficiency improvements.
3. State and local grants: Some states provide financial aid for home retrofits.
4. Low-interest energy loans: Special financing options for energy-efficient upgrades.

How to Find Available Programs

To find programs in your area:

• Check the Database of State Incentives for Renewables & Efficiency (DSIRE) – This website lists all available programs by state.
• Contact your utility company – Ask about available rebates and programs.
• Check with your state energy office – They can tell you about state-specific programs.
• Ask contractors – Experienced contractors often know about available incentives.

Planning Your Energy Efficiency Project

Improving energy efficiency of old homes can seem overwhelming, but breaking it down into phases makes it more manageable. Start with the improvements that cost less and save the most money. Then gradually work on bigger projects.

Here’s a suggested timeline for energy improvements:

Short-term Projects (1-3 months)

Start with these quick and affordable improvements:

• Air sealing – Caulk gaps and add weatherstripping around windows and doors
• Basic insulation – Add insulation to the attic if there’s little or none there
• LED lighting conversion – Replace all incandescent bulbs with LED bulbs
• Smart thermostat installation – Install a programmable or smart thermostat
• Water heater maintenance – Insulate your water heater and lower the temperature

These projects don’t cost much money but can provide immediate energy savings. They’re also easy to do yourself or with minimal professional help.

Medium-term Projects (3-12 months)

After completing the quick fixes, move on to these bigger improvements:

• Window improvements – Add storm windows or replace the worst windows
• Additional insulation – Insulate walls, floors, and basement areas
• Duct sealing and repair – Seal leaky ductwork and insulate ducts
• Water heater upgrade – Replace an old water heater with an efficient model
• Appliance replacement – Replace the oldest, least efficient appliances

These projects cost more money but provide bigger energy savings. You may need professional help for some of them.

Long-term Projects (1-3 years)

Finally, tackle the biggest and most expensive improvements:

• HVAC system replacement – Replace old heating and cooling systems
• Complete window replacement – Replace all windows with high-efficiency models
• Renewable energy installation – Add solar panels or other renewable energy
• Deep energy retrofit – Comprehensive improvements to make your home very efficient

These projects require significant investment but can transform your home’s energy efficiency. Plan carefully and take advantage of available incentives.

Maintenance Tips for Sustained Energy Efficiency

Once you’ve improved energy efficiency of old homes, regular maintenance is important to keep your home running efficiently. Here are key maintenance tasks to do regularly:

Monthly Tasks:

• Check and replace air filters in your heating and cooling system
• Check for new air leaks around windows and doors
• Look for any obvious problems with insulation or weatherstripping

Seasonal Tasks:

• Have your heating system serviced before winter
• Have your cooling system serviced before summer
• Check and clean dryer vents and exhaust fans
• Test and clean smoke and carbon monoxide detectors

Annual Tasks:

• Have a professional inspect your heating and cooling system
• Check attic and basement insulation for any problems
• Review your energy bills to look for unusual increases
• Consider having another energy audit to see if more improvements are needed

Environmental Impact

Energy efficiency improvements in older homes significantly reduce environmental impact:

• Carbon Footprint Reduction: Enhancing energy efficiency in older homes can lead to significant reductions in greenhouse gas emissions. For instance, adopting efficiency and electrification measures can reduce carbon emissions of single-family homes by 24%.
• Reduced Resource Consumption: Energy-efficient homes consume less electricity and fuel, thereby conserving natural resources and reducing the environmental degradation associated with energy production. This decrease in energy demand also lessens the strain on energy infrastructure, promoting a more sustainable energy system.
• Improved Air Quality: By lowering energy consumption, energy-efficient homes contribute to a reduction in air pollutants emitted from power plants and heating systems. This decrease in pollution leads to improved outdoor air quality, benefiting both the environment and public health.
• Extended Building Lifespan: Energy efficiency upgrades, such as improved insulation and ventilation, can protect building materials from moisture and temperature fluctuations. These enhancements help preserve the structural integrity of older home and extend their lifespan.

Wrapping Up

The measures outlined in this article can help you cut energy waste while maintaining the historic character of your older home. My husband and I are always trying to strike that balance: keeping the old architectural features of our house while tightening its efficiency for more sustainable living. The initial investment in energy improvements typically pays for itself through reduced utility bills and increased home value.

What is important is to consult with qualified professionals for major improvements and always check local building codes and preservation requirements before making significant changes to older homes. You want to avoid paying any fines for violating a code or rules of a historical district. 

Frequently Asked Questions About Energy Efficiency in Old Homes

Why are older homes often energy inefficient?

Older homes were built before modern energy codes. They often have poor insulation, drafty windows, and outdated heating systems, which leads to higher energy loss and utility bills.

What are the most cost-effective ways to improve energy efficiency in an old home?

Start with air sealing, attic insulation, LED lighting, and installing a smart thermostat. These low-cost upgrades can cut energy use by 15–20%.

Do I need to replace all my windows to save energy?

No, full replacement isn’t always needed. You can add storm windows, apply window films, or use thermal curtains to improve efficiency at a lower cost.

Is a home energy audit worth it for an old house?

Yes. A professional audit identifies where your home loses energy and suggests specific fixes. Many utility companies and states offer rebates or incentives to help cover the cost.