If you are ready to really get serious and make your home as comfortable and energy efficient
as you can then you want to continue reading the options below.
Increasing both your attic and wall insulation will reduce the amount of heat entering and
leaving your home, and will likely be more cost effective than doing each separately. Insulating
will make your house more comfortable and reduce your energy bills.
You can add attic insulation in two main ways: loose-fill or blown-in material, or blanket/batt insulation sold in rolls. For loose fill, call an insulation contractor. For batts, call a contractor or visit your local home/hardware center. Many people can install batts on a do-it-yourself basis.
Insulating the attic is also the best time to find and seal air leaks from the conditioned space. Look at attic hatches (can be weather-stripped, and insulation can be cut and affixed to the top), recessed ceiling light fixtures, pipe penetrations, or other visible air leaks. Use caulking or expanding foam to seal these leak areas. This is also a good time to ensure that your existing insulation is spread evenly throughout the attic, especially in the corners, and that the attic vents are clear of obstructions.
Insulating walls makes the most sense in the very cold and cold climate zones. In warmer climates, it is cost-effective only in certain cases: with a wood-frame wall, when there is no insulation present or when exterior siding is being added; for a masonry wall, when you are installing exterior siding or doing major rehab inside the house.
There are a few common ways to add wall insulation:
Blowing into wood-frame wall cavities: this is typically done by making temporary holes in the exterior siding and using a hose to blow in loose fill or expanding foam insulation products. These techniques can also reduce air leaks adding further energy savings.
Under siding on wood-frame walls: when you add or replace siding, it is easy and very cost-effective to add a layer of rigid foam insulation under the siding. It is also recommended to put an air-resistant housewrap under the insulation to reduce air infiltration.
For exterior insulation of masonry (block) walls, you can apply an exterior insulating foam system (EIFS), covered by stucco, brick, or siding finishes.
On the interior of wood frame or masonry walls: this makes sense if you are removing or rehabbing older walls or damaged plaster. It requires building out the inner wall to accommodate the insulation.
Whether you are insulating frame or masonry walls, this kind of work is typically not a job for the average homeowner; consult contractors who have this expertise.
If you are considering replacing your gas water heater, you should look for the most efficient model possible.
Your gas water heater uses a lot of energy even if you do not use a lot of hot water. Water heaters have standby
losses, which are minimized using heat traps and insulation in newer more efficient gas water heaters. Newer units
also have better heat exchangers and no pilot light. Look for one that has an Energy Factor (EF) of 0.6 or higher.
Depending on your usage habits, the incremental cost of purchasing a more efficient unit vs. a standard one is more
than paid for by the savings in energy that the unit will deliver over its lifetime.
If your furnace is old, worn out, inefficient, or significantly oversized, the simplest solution is to replace it. Consider upgrading your purchase with an Energy Star® model. Look for one with a Annual Fuel Utilization Efficiency (AFUE) of 90 or higher. Older furnaces can have AFUEs as low as 60 - 70. In climates with high heating demands, the incremental cost of purchasing a more efficient unit vs. a standard one is more than paid for by the savings in energy that the unit will deliver over its lifetime.
If you are considering replacing or installing a central air conditioner in your home, you should consider upgrading to the most efficient one possible. Look for one with a Seasonal Energy Efficiency Ratio (SEER) of 12.0 or higher. If your existing unit is 15 - 20 years old, it had an SEER of 8.5 - 9.5 when it was new, and has likely become even less efficient over time. In climates where the air conditioner runs frequently, the incremental cost of purchasing a more efficient unit vs. a standard one is more than paid for by the savings in energy that the unit will deliver over its lifetime.
If you use electricity to heat your home and are going to replace your existing heat pump, consider upgrading to an Energy Star® rated heat pump system. Heat pumps are the most efficient form of electric heating in mild climates, with efficiencies up to three times greater than electric resistance heating. High-efficiency heat pumps dehumidify better than standard central air conditioners, resulting in less energy usage and more cooling comfort in summer months. Look for one with a Seasonal Energy Efficiency Ratio (SEER) of 12.0 or higher and a Heating Seasonal Performance Factor (HSPF) of 8 or higher. In climates where the heat pump runs frequently, the incremental cost of purchasing a more efficient unit vs. a standard one is more than paid for by the savings in energy that the unit will deliver over its lifetime.
When it is time to replace your existing windows, consider upgrading from standard windows to Energy Star® windows. The relatively small incremental cost of Energy Star® compliant windows vs. the cost of standard aluminum dual pane windows makes Energy Star® compliant windows an attractive option. In Cold and Very Cold climate zones, low-e windows with insulated frames and gas fillers are recommended. In the Temperate and other moderate climate zones with significant heating and cooling loads, low-e windows with solar control features that limit solar heat gain are recommended to balance heating and cooling efficiency. In the hotter climate zones, the solar control features are most important. Look for window products bearing the NFRC label; which provides objective information on the window's heating and cooling performance.
Efficient windows are much more widely available than they were a decade ago, thanks to the rapid growth of new technologies.
Look for these features in efficient windows:
- Low-e coatings, which let in visible light but block radiant heat losses to cut heating bills.
- Solar control, or "spectrally-selective", coatings block out solar heat gain to save cooling energy but let in visible light.
- Insulated frames. Standard metal frames without insulation are the least efficient window choice – they conduct heat outside and can “sweat” in cold or humid conditions. Insulated vinyl, or vinyl, fiberglass, or wood frames with thermal breaks are much better choices.
- Gas fillers. The invisible gas filler in these double-pane units also makes a difference: instead of plain air, high-efficiency models are filled with argon or krypton gas, which conducts very little heat and help the window's insulating properties.
- Spacers. The material used to create the separation between the two panes of glass was traditionally metal. New materials are better-insulating and make the overall window more efficient.
For warm climate applications, retrofit tinting films can be applied to existing sun-exposed windows to reduce solar gain, cut cooling costs, and protect furnishings.
Replacing windows adds value in several ways: it improves the appearance and resale value of your home; reduces maintenance costs such as painting, and makes cleaning easier with tilt-sash designs. It improves comfort by making the area around windows feel warmer in winter, or by cutting down unwanted solar heat in summer. Another important benefit is reducing damage to your expensive furnishings by blocking ultraviolet light that fades fabrics, dries out fine woods, and harms heirloom photos and other items.
When shopping for windows, look for windows with National Fenestration Rating Council (NFRC) labels. These labels tell you how efficient the window product is, and also assures that the window has been tested and certified to perform at that level.
In the future, watch for Energy Star® labels on windows; these products will be the most efficient available, and the Energy Star® ratings will also help you select the right window for your climate.
Except for the experienced do-it-yourself carpenter, window replacement is best left to professional contractors.