Will A Metal Roof Save On My Heating And Cooling Bill?

       

The answer to this question is yes and no; it will save money on your cooling bill, but the effect will be negligible on your heating bill.

 In addition to no maintenance costs, a metal roof, especially aluminum, can lower your demand for air conditioning. According to the Florida Solar Energy Center, installing a simulated cedar-shake aluminum roof can reduce heat gain from the roof down through the ceilings by as much as 34 percent. Steel roofs, although not as efficient as aluminum, are also better than asphalt shingles. A metal roof cools down in five minutes once the sun sets.

An Energy Star rating for all roofing products is based on TSR (total solar reflectivity). Classic black asphalt shingles will have a TSR of only 0.05, while a quality aluminum roof will have a TSR of around 0.40. The larger number will mean that the roofing materials remain cooler and less heat will be radiated down through the ceilings to the living area. Also the underside of the aluminum metal surface has a lower emissivity (the ability to emit heat) than asphalt shingles, so less heat radiates downward.

Follow this link to an Energy Star roof calculator: http://www.roofcalc.com/    before making any roofing decision.

Metal roofs can save you as much as 20% on your summer utility bill by keeping your attic several degrees cooler. You can increase the savings by adding a radiant barrier under the metal roof to reflect even more heat rays.  A radiant barrier http://www.energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11680  can also be installed inside the attic as a retrofit on any metal or asphalt shingle roof. Avoid a horizontal application because dust from your insulation will reduce the radiant barrier’s effectiveness over time. The best application will be between the rafters up against the underside of the roof.

So the answer to this question is yes, a metal roof can reduce you energy bills. I will add that a radiant barrier alone will reduce your energy bills as will lighter color asphalt shingles or shade from large trees. A new roof can be an expensive proposition and it is always wise to calculate your ROI (return on investment) http://www.greenandsave.com/master_roi_table.html  on any improvement.

Energy improvements on an older home: where to begin

             Energy improvements on an older home: where to begin

Before the fuel crisis of the 1970s most Americans never thought twice about their home’s energy consumption. Many lived in older homes that had been retrofitted with electricity, indoor plumbing and forced air heating and cooling, and how efficient these systems were was less important than the fact that were simply there. Efficient and installed were synonymous!

The air conditioner brought an explosion of growth to the southern half of the United States that had once been declared “too hot for civilized people” to live year round. These systems were installed in homes that were not designed for such modern equipment and the results were mixed. Basically as long as the system was blowing cool air the house was cool. These homes were just not good at holding the cool air. So let’s discuss a few ways to bring these homes up to reasonable energy consumption levels. 

Below is my priority list, but it is okay to skip around some if you can’t afford the next measure.

1.     Seal all balloon framed walls and attic penetrations (plumbing, wiring, HVAC).

2.     Seal and insulate attic hatch.

3.     Seal and insulate knee walls in attic area.

4.     Insulate attic to R-30.

5.     Seal and insulate all forced air duct work.

6.     Install vapor barrier in crawlspace.

7.     Seal all plumbing and wiring penetrations in crawl space area.

8.     Caulk and weather strip around doors and windows.

9.     Install bath fans and range hood.

I would consider this list of priorities as a baseline before I purchased any type of energy saving appliances. Of course if the appliances or HVAC system need replacing before you complete the list, do so with Energy Star models. 

I would also consider having a blower door test conducted by a qualified individual before attempting any work. By doing this problem areas can be identified and large amounts of air infiltration/exfiltration can be eliminated. It is a good idea to have the testing done by an impartial person and not a company that wants to sell you the improvements.

Homework

                                                          

The first day of Spring is right around the corner! Now we can spend a little time outside instead of looking out the window and saying, “boy it looks cold out there”. As bad as I hate to admit it that is what happens at my house. I tolerate cold weather, but the novelty does wear off eventually and I hate it. So get outside and enjoy the warmer weather and when you have a little free time…how about some energy saving homework!

Rebates and incentives are available from the power companies to throw you in gear, but if you’re like me you would rather do it yourself and not have a stranger looking at your junk. I can only say that my wife is collecting stuff for a yard sale so many times before it begins to sound stupid even to me, so let’s minimize outside labor. Here is a good way to get started. Turn on every appliance that exhausts outside the “envelope” of your home. This would be bath fans, range hood and clothes dryer. This will put your home under negative pressure (more air going out than is coming in) similar to what a blower door will do, but on a smaller scale. With a lighted stick of incense in hand walk around your home and test areas you suspect air to infiltrate. Suspect areas would be:

1.       *Doors and windows.

2.       *Plumbing penetrations in cabinets.

3.      *Fireplaces.

4.       *Light switch and receptacles.

5.       *Attic access.

6.       *Whirlpool tubs and shower stalls. (this will be covered in another blog about     dealing with the giant hole under bath tubs)

7.       *Duct registers and return grills.

If you don’t like using the smoke, just use your face. The skin there is very sensitive and you will feel the air moving against it, but the smoke is a great visual aid.

If you choose to use spray foam to seal some of the leaks you find, be careful. It takes a little practice to not get it everywhere, and once it’s on your skin, you will wear it for a while. Latex caulk is much easier to use because you can wash away your mistakes. If you choose to caulk larger holes, go at it in stages by allowing the initial application to harden and apply in layers.

This is the basic premise of air sealing. It is a homeowner friendly sport and it will save you dollars. Keeping the conditioned air in your home is very important and will save you money. Insulation alone will not hold the air in your home; it will only filter the escaping/infiltrating air. I will add that an official blower door test is a good idea for everyone. This will insure that you home is not too tight, but it has been my experience in the hundreds of homes that I have tested that few are too tight! In a future blog I will cover homeowner friendly duct sealing, attic and knee wall sealing and large hole repair. Until then….enjoy the changing season!