Energy FAQ's
Do you have questions about your home's energy use, saving money on energy costs, or improving your home's efficiency? Ask your questions here and our home energy experts will provide answers.
Search FAQ's by subject:
Roofing/Siding
We need to replace our roof this year and would like to know which types of roofing are most energy-efficient?
The type of roofing you choose can have a tremendous impact on the energy efficiency of your home. You may even qualify for a Federal Energy Tax Credit.
- Metal roofing reflective, very durable and stands up well to extreme weather.
- Clay and concrete tiles are sustainable materials that are popular for energy-efficient roofing. Some tiles can have an additional energy-efficient coating added. You can also get roof tiles with solar panels on them to absorb solar energy for use in the house.
- Membrane roofing is easy to install, durable and long-lasting. It is often used on commercial buildings for its durability. Membrane roofing can be expensive, but worth it if you intend to live in your home for many years.
- Sprayed-on polyurethane foam roofing is affordable, leak-proof and energy-efficient, but not the most attractive roofing material. It is often used on flat or hidden roofs because of its appearance, although it is possible to apply it to sloped roofs as well.
Insulation
Is there an easy way to tell if I have enough insulation in my attic?
A rule of thumb is that if you can see the joists in your attic, you need more insulation. But even with lots of insulation it’s very important to seal any air leaks or your insulation won’t be performing as effectively as it could.
Heating and Cooling
I've been told to change my air conditioning or furnace filter each month. Is this really necessary?
During winter and summer when your heating and cooling systems are working the hardest, it’s a good idea to check the filters each month and replace them if they’re dirty. At other times of year, you should replace your filter at least every three months. The dirtier your filter the harder the system has to work to do its job. This harder work takes energy, resulting in a higher energy bill. Also, changing the filters regularly will keep the system freer from dirt build-up, which can lead to system failure.
What is the SEER rating of an air conditioner?
SEER stands for “Seasonal Energy Efficiency Ratio”. It is a measure of the energy efficiency of cooling products, which allows consumers to compare operating costs of various cooling systems and products.
SEER = [Cooling Output] / [Electrical Energy Input] for an entire cooling season. The thing to remember is that higher a SEER rating means greater efficiency (and therefore less cost to cool the building).
Beyond the SEER rating, other factors affect the cost of cooling a building, such as building insulation, air leakage, room layout, quality of windows and adequacy of the duct system.
How can I lower my heating costs?
- Lower your thermostat. By lowering your thermostat by 1 degree you can save about 3% on your heating costs.
- Use a programmable thermostat to adjust the temperature when you are asleep or away from home. Set the thermostat to reduce the temperature at least an hour before bedtime. You likely won’t notice the change in temperature before you go to bed, as it takes awhile for the house to cool down.
- Put on a sweater. This will allow you to lower the room temperature and still stay comfortable.
- If some rooms in your home are too warm and other are too cold, your heating system is unbalanced and needs to be adjusted. Call a professional.
Windows/Doors
Can you explain U-values and R-values?
U-values are used to express the amount of heat that is transferred through a window by conduction, convection and radiation. So, the lower the U-value the better.
R-value is used to express the resistance to the flow of energy. A higher resistance to energy loss – and thus a higher R-value – is better. Note that the R-value equals the mathematical inverse of the U-value. So a window with a U-value of 0.5 will have an R-value of 2.
What are Low-E windows?
Low-E windows are windows which have a special coating that limits the transfer of heat through the window. In cold weather, less heat escapes through the window glass, keeping more heat inside the house. As a result, your furnace doesn’t need to work as hard and you save on your energy bills. In warm weather, Low-E windows keep the heat out, so the inside of your house stays cooler. As a result, your air conditioner doesn’t need to work as hard and you save on your energy bills. Low-E coatings have about the same insulating value as an additional pane of glass – so a double-glazed low-E window insulates about as well as a triple-glazed clear window.
Indoor Air Quality
How can I prevent mold growth in my home?
Mold grows in damp environments. It is often found in basements, on walls, windows and damp carpets. You can help prevent mold growth by reducing indoor moisture levels. Try the following suggestions:
- During the winter season, maintain a relative humidity in your home between 25 and 35 per cent
- Ensure proper venting of moisture from the kitchen, bathroom and laundry area
- Do not hang excessive amounts of clothes indoors to dry
- Provide adequate ventilation or use a dehumidifier to remove excess moisture from the basement
- Make sure window caulking is in good condition to prevent leakage, indoor moisture and water damage
Solar
Is it possible to power my whole house with solar energy?
Yes, it is possible, although it is sometimes necessary to power high-load appliances such as refrigerators and clothes dryers with alternate means. With stand-alone systems you store energy in storage cells for future use. With grid-connected solar systems you sell your excess energy to the utility company, and buy back energy only when you need it.
How much do solar energy systems cost?
The cost of a complete solar energy system would depend on your energy needs, how well you conserve energy, and which system components you choose. Solar kits that can power RV’s, boats and small homes can cost under $400, while a system to power your entire house will cost several thousand dollars.
Handyman
What improvements can I do around the house that are easy and inexpensive?
Caulking and weather stripping are under estimated in their importance for saving energy. Applying caulking around window frames and weather stripping on doors can have the same impact as shutting an open window. You may choose to do these projects yourself, or hire a handyman who can do other odd jobs at the same time, like painting, repairing drywall, cleaning eaves troughs, etc.
Remodeling
We’re remodelling our bathroom. What can we do to make it more energy-efficient?
- Install a low-flow shower head, toilet and faucet, which will save a significant amount of energy and water.
- Insulate all exterior walls and floors above unconditioned spaces to at least R-11 (recommended for northeastern US states). The added cost is minimal, and will pay for itself in about 2 ½ years.
- Have a professional seal your home’s air leaks, and in particular seal around plumbing and electrical penetrations – especially recessed lighting – in the bathroom. Although it will cost around $500, you can save about $175 each year. The improvement will pay for itself in about 3 years, and after that the savings are yours to keep.
- Add adequate ventilation in the bathroom, ensuring that the exhaust fan vents to the outdoors.
- This is a good opportunity to open outside walls behind tubs and showers which are often poorly insulated and air sealed, and install insulation and seal air leaks with caulk or expanding foam.
Home Automation
Backup Generators
I was planning to buy a portable generator as a backup power source during power failures, but I’m being advised to consider a permanent generator. Is a permanent generator really worth the extra cost?
It really depends on your needs and your budget. A portable generator can get you through a power outage and keep various appliances running, such as your fridge, furnace, lights and security system. However, there is a limit to the number of devices that can be plugged in at one time. Portable generators are also quite loud, very heavy and hard to move, and run on gasoline. A permanent generator can run off your home’s natural gas or propane supply, and can be wired directly into your home’s circuit panel and switch on automatically to power your entire home’s needs when the electric power fails. Permanent generators are also much quieter than portable generators. It is a good idea to have a backup power source for power failures, but ultimately the choice between a portable generator and a permanent one depends on the level of comfort and security you desire during a power outage.
Plumbing
Appliances
How much more cost-efficient is a ceiling fan compared to a window air conditioner?
While a ceiling fan may not provide the same cooling effect as an air conditioning unit, it can reduce the perceived temperature by 3 or 4 degrees, which many be a sufficient cooling effect on most days.
Consider that it costs 1 to 2 cents per hour to run a ceiling fan, compared to 25 cents (approx.) per hour to run an air conditioner (assuming 12,000 BTU, 9-10 EER).
On hotter days when it is necessary to run the air conditioner, it can save you money to run both the ceiling fan and the air conditioner at the same time. While this may seem counter-intuitive, the ceiling fan works to distribute the cold air from the air conditioner throughout the room, making the air conditioner work less, thus saving you money.
How can I use my appliances more efficiently to save money on my energy bill?
Here are a few tips:
- Run your dishwasher only when it's completely full, and use the energy-saving settings if available
- Run your clothes washer only when you have a full load of laundry
- Whenever possible, wash your laundry with cold water
- Clean your clothes dryer's lint tray before each load
- Avoid overloading the clothes dryer as this will make it work harder
- When replacing any appliance, look for Energy Star-labelled products, which provide significant energy efficiency and savings
Is it more cost-effective to re-heat food in the microwave or on the stove?
It costs roughly 2 to 4 cents to run your microwave for 10 minutes, compared to about 38 cents to run the stove for the same amount of time. Also consider that food cooks faster in the microwave, requiring less time.
Radon Services
Mold Remediation
Electrical
Public Information
Realtors
General
What are some inexpensive improvements I can do to make my home more energy efficient?
There are several things you can do easily and cost-effectively that will save you money on your energy bill each month.
- Replace incandescent light bulbs with fluorescent. While the fluorescent bulbs are more expensive initially, they last much longer and use far less energy. They will pay for themselves over time and they are better for the environment.
- Add insulation in your attic. This is where most of your heat escapes from.
- Seal any cracks or leaks that let outside air into our home.
- Insulate and seal the air ducts running through your attic or crawlspaces.
- Replace older, less effective appliances or heating/cooling systems with new, efficient models. You may not consider this to be inexpensive, but if you can afford it you will see saving immediately on your energy bills.
The auditor did a TERRIFIC JOB! The report was FANTASTIC! I will make all the repairs he suggested. I will definitely recommend him to everyone I know that could benefit from a home energy audit.









