Why is my house so cold—and how do I fix it?

Here’s how to get back the warmth you’ve been missing.

Here’s how to get back the warmth you’ve been missing.

Cold weather’s back, and once again you’re left wondering why is my house so cold—even with the heat on?

And it’s not just that your house feels chilly inside on winter days; it’s that you have to crank your heater up just to stay warm. You’re never comfortable—no matter how high you adjust your thermostat!

But a cold house isn’t just unpleasant. It can be bad for your health and the health of your home, too.

If you’re tired of shuffling from drafty room to drafty room, you’ve found the right place. In this article you’ll learn:

To get started, let’s cover why your house might be so cold in the first place.

(Quick tip: Depending on where you live, you could get upgrades to make your home healthier and more comfortable year round at no upfront cost with Sealed.)

The reasons why your house is so cold

When you’re stuck shivering in your living room while the heat is cranked—or laying awake on winter nights wondering Why do I feel cold in my house?, it’s easy to assume that your heating system is to blame. But that’s not always the case. 

Here are 7 reasons why your house might be hard to heat, grouped by minor fixes and big problems.

Minor fixes

  1. You need a new filter. Changing your HVAC’s air filter could improve your home’s heating efficiency. But it’s likely there’s something else going on, especially if you already change your air filters regularly.
  2. Your thermostat isn’t working correctly. If the issue is not your filter, it might be your thermostat. (Read on! We’ll discuss this issue more thoroughly below.)
  3. Your heating system needs a checkup. If the problem is not your filter or your thermostat, and if you don’t get regular annual maintenance on your HVAC system, it’s time to do a routine check up to make sure your system is operating at its best. You may need a furnace repair or replacement to get your heated air going through the house again.

Big problems

  1. Your heating system needs replacement (or it’s insufficiently sized for your home). Okay, so this is the obvious one. Maybe you do have a problem with your furnace, boiler, or heat pump, or perhaps it’s too big or too small for your home. This might be the case if you have one heating system for a two-story home or if your heater is oversized to overcompensate for heat loss throughout your home. Or maybe, it’s just simply time to replace your old heater.
  2. You have insufficient insulation. Your house and attic insulation can wear down over time. Your house also may have hidden attics that aren’t properly insulated or uninsulated garage walls that are attached to your home, and this can cause problems with heat escape, unwanted airflow, and drafts.
  3. Your ductwork has problems. You’ve had your heater checked and it’s working fine, but perhaps the older ductwork in your home has leaks and gaps that are causing heat to be misdirected throughout your house.
  4. Air leaks are causing heat loss in your house. This is a big one. Every home has air leaks—they’re in your attic, along the foundation, and around plumbing and lighting fixtures. We can’t emphasize this enough: If your house hasn’t been professionally air sealed and insulated, it’s likely this is one of the major reasons your house is so cold. Learn how to find air leaks here.

You may also be asking yourself: Why aren’t windows on this list? Great question. Many homeowners believe that their drafty windows are the cause of their climate control issues, but most of the time, windows aren’t the real culprit (although window companies would like you to think so).

If your house is experiencing heat loss, a lot of heat you’re paying for—as much as 30% to 50% during the winter months—is escaping through your attic (1). Not your windows.

Even if you install new windows, you’ll still have open gaps and seams around them if you don’t get them air sealed.

Your house shouldn’t feel like an igloo. To find out what igloo science and your house have in common, read How are igloos warm inside?

Why is my house not staying warm? How heat escapes from your home

If you’re asking yourself Why is my house so cold even with the heating on? or Why is my house not staying warm?, the truth is that air leaks—along with insufficient insulation—cause heat to escape directly from your home. 

As heat rises in an under-insulated and unsealed home, it escapes through gaps in the ceiling and is lost through the top of your attic.

And as your paid-for heat escapes through your attic, it creates a vacuum that sucks in cold air from the outdoors. This causes your home to feel drafty—especially in areas near windows and doors. Read How to fix a drafty door for step-by-step help.

In fact, as air leaks through the gaps, cracks, and holes throughout your house, it adds up to a lot of heat loss—even if the individual leaks themselves are tiny. (Air leaks also cause high energy bills.)

Check out this video below for a good visual of how this works:

Ultimately, yes, your cold house is losing valuable heat, but when that vacuum is created, your house is also pulling in moisture and allergens—both of which aren’t healthy for you or your home.

Through thousands of Sealed home audits, we’ve found houses exchange air at 3–4 times the rate they should because of air leaks. (That’s like having a window in your house open 24/7, all year long.)

That’s why replacing your windows won’t necessarily solve the problem. It’s usually the holes around windows that are letting the cold air in—not the windows themselves.

Listen, if your home isn’t properly insulated or professionally sealed, you’re already losing heat.

Combine that with an insufficient heating system, or even an energy-efficient heater that’s hampered by air leaks and poor insulation, and you have the perfect recipe for a continuously cold home.

And that also means your heating system is definitely overworked and operating at reduced efficiency.

To learn more about how air sealing your home prevents heat escape and air quality issues, check out our Guide to Air Sealing. (This guide also tackles the myth of having a “too tight” home.)

If your home isn’t properly insulated or professionally sealed, you’re already losing heat.

mature man reviewing the thermostat to make a cold house warmer

What to do if your house is colder than your thermostat reads

The majority of cold weather comfort issues are caused by heat escape, poor insulation, and inefficient heating systems. But there’s another problem you should know about: your thermostat.

If your house is colder than your thermostat reads, take these steps:

  1. Check the battery. You might just need a new battery. Try this step first.
  2. Clean it. Sometimes the temperature sensor is blocked with dust or dirt. A quick clean might be all it needs. Check with your specific thermostat’s product guide for specifics.
  3. Determine when it was last replaced. Thermostats last about 10 years, so if yours is getting old, it may be time for an upgrade.
  4. Make sure there isn’t a source of cold or heat nearby. Is there a heat source that is affecting its temperature readings? Is it too close to a window? Is there a draft?
  5. Recalibrate your thermostat if needed. Sometimes, your thermostat can be reading the temperature incorrectly. Recalibrate it according to the manufacturer’s directions.

Need a new thermostat? Learn more about smart thermostats (and how to get one). They can actually learn your temperature preferences and help you use a lot less energy to heat and cool your home.

But if your thermostat is working just fine and you’ve still got a cold house with the heat on, it’s important to take steps to resolve it.

Is a cold house bad for your health?

Here’s the thing: It’s easy to dismiss a cold house as just that—a cold house. But it can be bad for your health, especially the health of older people and young children.

A too-cold house is usually an indicator of a larger problem with your home’s airflow, one that causes heat loss and air quality problems. Learn more about keeping your home’s air healthy and clean.

According to the WHO Housing and Health Guidelines, cold indoor temperatures have been associated with increased blood pressure, asthma symptoms, and even poor mental health (2). And poorly-heated houses have also been found to contribute to winter deaths.

The good news is your cold house doesn’t have to stay cold. Here’s how to fix it.

How to make a cold house warm

Air leaks are a cause of a large heating and cooling burden on your HVAC system—and they cause heat to escape your house. That’s a big problem, but one that—thankfully—has a straightforward solution.

First, we’re going to talk about a few ways to permanently fix a too-cold house. Then we’ll dive into some quick-fix solutions if you need to warm up your place while you’re waiting.

Steps to permanently make a cold house warmer

  1. Determine where you’re losing the most heat in your home from a professional energy audit from your local utility company. (Often, these are free or come at a low-cost!)
  2. Get professional air sealing for your home and attic to seal up air leaks that are causing heat escape.
  3. Upgrade your existing home and attic insulation to help create a solid thermal barrier to keep heat inside. (Plus, learn how insulation upgrades save energy here.)
  4. Check and repair ductwork if needed. 
  5. Install a new, energy-efficient home heating system if your last HVAC system needs replacement. (We recommend an electric air-source heat pump—the Tesla of HVAC. Learn why heat pumps are so cool.)
  6. Enjoy a warmer house in the winter.

Talk to a climate control expert to determine which custom cold house solution is best for you. (It’s 100% free.)

Practical tips to make your cold house warmer right now

If you need fast solutions to make your house warmer today, here are some quick tips:

  1. Use blinds and curtains to trap in heat. Open insulated curtains during sunny cold days to let in warmth, and close them to trap heat in at night.
  2. Try space heaters. This isn’t a long-term solution—space heaters have safety concerns and are energy wasters. But these can be a fast remedy if you need to warm your house today.
  3. Use draft stoppers with exterior doors. Applying a draft stopper at the bottom of exterior doors can help reduce heat escape, and you can find them at most hardware stores.
  4. Warm up with a heating pad or heated blankets. Using electric heat via an electric blanket can be a temporary way to stay warm. However, this is a short-term fix.
  5. Add fresh weather stripping to doors and windows. This can help you feel warmer and reduce drafts in your house.
  6. Use your fireplace. If your fireplace is in working order, use it to boost your home’s heat until you can take steps toward permanent solutions.
  7. Or block off your fireplace. If your fireplace isn’t in working order, consider blocking it off so it’s not contributing to your home’s heat loss.
  8. Open up the linen closet. If you’ve got extra blankets and sheets, use them to stay warm and to temporarily block drafts coming from side attics or unused fireplaces.

Okay, but what if you only have one really cold room? Or a couple cold rooms, and the rest of your home is comfortable?

Read How to stay warm in a cold house for more quick tips. Or learn how to fix cold floors for good.

How to fix a cold room in your house

Sometimes your overall home might be comfortable, but you have a room that just doesn’t stay warm in the winter. 

First, you should know that this kind of problem is usually a symptom of a poorly-sealed house or under-insulated house (even basement insulation matters here!). But there are a few steps you can take to diagnose the issue:

  • Check your heater and room vents to make sure warm air is actually flowing to the room. 
  • If heat is flowing to the room, this room may have insulation issues that are causing heat to escape.
  • If heat isn’t flowing to the room at all when your heat is on, there may be leaks in your ductwork or an issue with your furnace, boiler, or home heating system.

This is a situation where having expert help can really save you time and frustration. Get a free consultation from Sealed.

Learn more about when to replace your home heating system and discover how electric air source heat pumps allow you to do custom temperature zoning.

Get the permanent solution for a cold house. Pay no upfront costs.

Ready to solve your cold house problem once and for all? 

Depending on where you live, you can get home upgrades that keep you warm and healthy with no upfront cost. Yes—really. Learn how.

We stand by our work 100%, too, with an energy-savings guarantee.

Fill out our fun, 2-minute questionnaire to see if your house qualifies.

5 energy efficiency myths FREE ebook animated gif

Check out our FREE home comfort guide to learn how to make your house feel better year round

Case studies and checklists included

Get your copy

November 22, 2021