Key takeaways
- Most heat in older homes escapes through air leaks and under-insulated attics, walls and basements.
- Equipment age and settings matter too, but fixing the building shell usually comes first.
- A home energy assessment or blower door test shows where your money is going.
- Mass Save® incentives cover much of the cost of air sealing and insulation for eligible customers.
It is not just the price of fuel
Massachusetts has some of the highest energy prices in the country, and winters are long. But two neighbors on the same street, with the same size house and the same fuel, can have very different bills. The difference is almost always the house itself: how much air it leaks, how well it is insulated and how efficient its heating system is.
9 common causes of high heating bills
1. Air leaks at the attic floor
Warm air escapes through gaps around chimneys, plumbing stacks, light fixtures and the attic hatch. This is usually the largest single loss. See air sealing before insulation.
2. Thin or settled attic insulation
Many homes have 3 to 6 inches of old insulation. Current recommendations for Massachusetts are R-49 to R-60, roughly 14 to 18 inches of blown insulation. See how much attic insulation you need.
3. Empty exterior walls
Homes built before about 1960 often have no wall insulation. Dense-packing them with cellulose makes a big difference.
4. Leaky basements and rim joists
Cold air enters at the foundation and spreads through the house. See rim joist insulation.
5. Leaky ducts in unheated spaces
Forced-air systems with ducts in the attic or crawl space can lose a lot of heat before it reaches the rooms. See duct sealing.
6. An old or oversized heating system
Older boilers and furnaces are less efficient, and oversized systems short-cycle. But replace equipment after fixing the shell, so the new system can be smaller.
7. Thermostat habits
Big setbacks in a slow-responding system, or space heaters fighting the main system, can waste energy. A smart thermostat helps.
8. Unheated spaces you are heating anyway
Rooms over garages, three-season porches and finished attics with poor insulation pull heat from the rest of the house. See cold rooms over garages.
9. Hot water
Water heating is often the second largest energy use. Pipe insulation and an efficient water heater help.
Where to start
| Step | Cost | Impact |
|---|---|---|
| Home Energy Assessment | No cost (Mass Save®) | Shows your biggest losses |
| Attic air sealing | Often no cost (Mass Save®) | High |
| Attic insulation | Rebated (Mass Save®) | High |
| Wall insulation | Rebated (Mass Save®) | High in pre-1960 homes |
| Rim joist sealing | Moderate | Medium to high |
| Heating system upgrade | Higher | Depends on age and fuel |
A blower door test shows how leaky your home is, and an infrared scan shows where the heat escapes.
Mass Save® makes the first steps affordable
Eligible customers can get a no-cost Home Energy Assessment, no-cost air sealing and rebates on approved insulation. For many households, the most effective improvements cost far less than expected.
How to compare your bills fairly
Heating bills vary with the weather and with fuel prices, so comparing one January with the next can be misleading. Better ways to compare:
- Use quantity, not dollars: gallons of oil, therms of gas or kilowatt-hours, rather than the total cost.
- Adjust for weather: compare usage per heating degree day if your utility provides it.
- Compare full seasons: October through April gives a more reliable picture than a single month.
What a "high" bill looks like for your house
There is no single number, because homes vary in size, age and heating type. But some signs suggest your house uses more than it should:
- Your neighbors with similar homes spend noticeably less.
- Your heating system runs almost constantly on moderately cold days.
- Some rooms never get warm no matter how high the thermostat is set.
- You get ice dams every winter.
Quick wins this week
| Action | Effect |
|---|---|
| Lower the thermostat a few degrees at night | Less heat lost overnight |
| Close the fireplace damper | Stops a major leak |
| Replace furnace filters | Better airflow and efficiency |
| Weatherstrip the attic hatch | Seals a common large leak |
| Bleed radiators | Hot water systems heat more evenly |
Fuel-specific notes
- Oil and propane: price swings make efficiency especially valuable. Every gallon saved stays in your pocket.
- Natural gas: generally lower cost per unit of heat, but older homes still waste a lot.
- Electric resistance: baseboard heat is expensive to run; air sealing, insulation and a heat pump can make a large difference.
When to call a professional
If your bills are rising and you cannot explain why, an energy assessment or audit will show where the heat goes. It is often the fastest way to cut costs, and in Mass Save® territory it is offered at no cost to eligible customers.
Lower your bill this winter
BCI Group helps Massachusetts homeowners find and fix the real causes of high bills. Call (774) 278-8256 or request a free estimate.
Frequently asked questions
What is the biggest cause of high heating bills?
In most older homes, air leaking through the attic and basement, combined with too little insulation, is the biggest cause.
Will a new furnace or boiler lower my bill?
It can, especially if your system is very old. But fixing air leaks and insulation first lets you buy a smaller, cheaper system.
How do I find out where my heat is going?
A home energy assessment, blower door test and infrared scan show where heat escapes.
Are space heaters a good idea?
They can help in one room but are expensive to run as a main heat source. Fixing the room’s insulation is usually better.
Does Mass Save® help with high bills?
Yes. The program offers a no-cost assessment, no-cost air sealing and rebates on insulation for eligible customers.
Services mentioned in this article
Insulation Contractor near you in Massachusetts
BCI Group crews work in these communities every week. See local details for insulation in your town:
