Myth Busters
Myths about home problems, and their solutions, have grown along with our expanding desire for comfort and space. As a result, many people spend time and money on the wrong solutions. Before committing to an improvement, be sure you truly understand the cause of your problem and the real solution. Click on a link below to learn more about some of the leading home myths:

New windows will lower my energy bills and prevent water and frost build-up in the winter.
A house has to breathe, so it’s fine to not seal all the air leaks.
Adding insulation will keep my house from being too hot in the summer and too cold in the winter.
Adding insulation will stop ice dams from forming.
All I need for a comfortable house is NASA tested radiant barrier insulation.
Kitchen ventilation is not necessary.
It’s too expensive to install a high-efficiency furnace or water heater.

What’s Myth and What’s Reality?



New windows are the only solution for high-energy bills and water/frost build-up in the winter.


1.    Unsealed gaps between windows and wall frames commonly cause drafts. You may only need to seal them with foam to lower energy bills.

2.    The walls around the windows may need more insulation to feel warmer.

3.    Broken seals on double-pane windows will lower the windows’ insulating ability. Replacing the window glass rather than the whole window can save you a bundle!

4.    Excessive home humidity can cause wet, frosty windows. You may solve the problem with whole house ventilation and new kitchen/bath exhaust fans.

Not sure what to do? Enlist the help of a Certified Energy Professional to test for air gaps and ventilation problems.



A house has to breathe, so it’s fine to not seal all the air-leaks.


A house does need to have fresh air coming in and stale air, pollutants and moisture going out – but not at the expense of your energy budget and comfort! Go ahead and seal-up those expensive, drafty gaps and then add a dedicated ventilation system. This may include an air exchanger, heat recovery ventilator, or new kitchen/bath/laundry exhaust fans. Build it tight and ventilate right!

A Certified Energy Professional can test and calculate the ventilation needs of your home. He can also test for carbon monoxide and other pollutants before and after any changes are made.



Adding insulation is all I need to keep my house from being too hot in the summer and too cold in the winter.


More insulation can only help if you’ve sealed the air leaks in your home first. Just like a cold wind blows right through your bulky knit sweater, air blowing through insulation reduces its effectiveness. Typical air leaks in your home occur around wiring, windows and doors, rim joists, and plumbing, ducts, and vents that go through the attic floor.

Need help? A Certified Energy Professional uses special equipment to pinpoint visually undetectable air leaks, and identify gaps or settling in existing insulation.



Adding insulation or attic ventilation will stop ice dams from forming.


Ice dams form when snow melts on a warm roof. Adding insulation is only one part of the solution. The key is to keep the roof cold by preventing inside heat from reaching it.  Adding more attic ventilation may help to remove heat from the attic but done without fixing the problem of heat escaping into the attic will actually make the problem worse.  (Negative pressure in the attic pulls more air from inside the house though the leaks)

Taking these three steps – in order – can solve your pesky ice dam problem:

  1. Seal all cracks, gaps and holes between living space and the attic to prevent warm air from getting into the attic and heating the roof.
  2. Add enough attic insulation to have at least a value of R-30. (More is better) Use spray foam in tight spots such as near exterior walls to increase the insulation value in tight spots
  3. Add vents and chutes at the soffits, and passive vents near or at the roof peak to release any heat that does make it into the attic.  (Don’t use powered attic fans)

For tough to reach spots over exterior walls an excellent time to make these upgrades is when you’re replacing the roof. Overwhelmed? Enlist the help of a Certified Energy Pro who will pinpoint problem areas. Her recommendations are helpful whether you do the work yourself or hire a professional.



All I need for a comfortable home is NASA-tested radiant barrier insulation.


Have you ever heard a snappy sales pitch for fabulous insulation developed by NASA that works like a miracle and saves you money? The science behind these claims is mostly misrepresented. Radiant barrier insulation works in space, but is not a good solution for your attic. An Oak Ridge National Laboratory study found that it is not effective in Minnesota – and that air sealing and/or adding insulation are better options.

Worse yet, a radiant barrier can trap household moisture making the insulation wet, lowering its R-Value, growing mold and creating a mess. Just say NO to this product!

A better strategy is to learn about the problems that lead to discomfort in your home – lack of insulation, air gaps, heating and cooling equipment issues, window problems, etc. If you aren’t sure, enlist the help of a Certified Energy Professional who will diagnose the isues and develop real solutions.



Kitchen hood fan vented outside is not necessary.


This couldn’t be farther from the truth! Cooking food on gas or electric stoves releases stuff that makes a mess of your clean indoor air and your lungs:

  • Smoke
  • Fine particles
  • Toxins
  • Carbon monoxide and other pollutants (natural gas/propane stoves)
  • Excess heat that harms nearby surfaces
  • Excess moisture that harms cabinets, walls, windows and attic

Many homes may have a recirculating fan installed.  This was common in the 80’s and 90’s.  Simply put-they are worthless. While a filter can trap some grease and odors, heat, moisture, and cooking toxins stay inside.

If you are planning to add kitchen ventilation, here are some tips:

  • Get an exhaust system correctly sized for the dimensions and location of the cooking surface and the amount of heat produced. Otherwise the manufacturer may void the warranty of any damaged appliance.
  • Be sure the exhaust system has insulated, rigid metal ducts that vent to the outside not the attic.
  • Ventilation systems in today’s homes should consist of 2 parts – the exhaust system and a make-up air system that brings fresh air into the home. Make-up air is a safety measure that reduces the risk of carbon monoxide pollution from fuel burning furnaces, water heaters, and clothes dryers. Your appliance retailer and/or mechanical contractor can help with both parts.
  • If you are uncertain about what to do, work with a Certified Energy Professional. Her expertise will help you plan a safe, healthy, durable home in a cost effective manner.



It’s too expensive to install a high efficiency furnace or water heater.


High-efficiency equipment may cost 25% more up-front, but then save 15% on energy use year after year. That’s a good deal! The investment is worth it even if you plan to move in a few years. Today’s buyers are looking for energy efficient homes. In fact, Minnesota energy code prohibits installation of inefficient furnaces and water heaters in new homes. Why would you install them in yours?

Buying a new high efficiency furnace or water heater is a long-term capital investment – typically 20 years for a furnace and 10 to 15 for a water heater. Here are some tips to help you make a confident decision:


  1. When you’re upgrading to higher efficiency equipment, there may be some installation challenges:
    1. The new equipment requires a PVC flue pipe rather than the old metal one.
    2. Finding a way to vent the new equipment can be a puzzle depending on its location and other structures in the house.
    3. You may need to replace your water heater at the same time as the furnace in order to use the old chimney as a pathway for the PVC pipe. 
    4. You may have to cut a hole or two in the basement’s finished ceiling. Not ideal, but worth it for a 20-year investment.
  2. Some installers may not like to deal with the extra steps to ensure proper installation and maximum efficiency. Keep this in mind if they try to steer you to lower efficiency equipment. It’s more profitable for them to install 3 low efficiency furnaces in a day than one high-efficiency unit. Choose your contractor wisely.
  3. A Certified Energy Professional is a neutral party who can evaluate your existing mechanical systems, how they interact, and the impact of new equipment. He can suggest ways to relocate the new equipment, and assess the impact of a new furnace on the ventilation of your existing water heater. His recommendations will help your installer do a better, faster job.
  4. Be proactive.  Don’t wait for it to fail. If possible, buy new equipment in the spring or fall when contractors are less busy and have more time for your needs. Get multiple quotes and read them thoroughly. If you have questions about the quoted equipment and processes get help from your Energy Pro.  
  5. It’s your home and investment – take the time to get the best deal for you!

Next steps

1. Read the Most Important Step

2. Find a Certified Energy Professional

3. Enlist services of a home performance contractor

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