Category Archives: Energy Audit

Using One HVAC System for Two Areas

My first audit was triggered by the homeowner concerned that the upstairs was several degrees warmer than downstairs. Since we all have experienced Hot Air  goes up, it makes some sense.  In this case the difference was 15° F at 8:00 am, rising to 20° F by noon that August morning.  Yes, it was hot.

4 square craftsmanThere are a number of ways to help this out, for existing homes. Which one is best depends on the specific home, the existing setup and the homeowner.  For new homes, it usually falls to the HVAC guys to work out.

In a new 2 story home, it is common to see two HVAC units.  One in the basement for most of the home and one in the attic for the second floor.  Some builders, concerned with cost, or space considerations, will try a Zoned System.  You can also find Zoned Systems in single story homes, with the master suite on one zone and the rest of the home on another zone.

furnace bypass zoneTypically, the set up uses a bypass and several dampers to control the air.  The wisdom of this approach is that changing the air flow through the unit costs a lot of $$$$.

In the video below, John Proctor, goes through the measurements and calculations of using or not using a bypass and dampers to figure out exactly what is happening.  His conclusion:  The Bypass Damper set up costs 22% – 32% more.

This video is primarily written for HVAC contractors and others interested in the details and workings of air conditioning.  If all the numbers make your eyes glaze over, that is OK.  All you want is comfort, a Bypass dampened system may do that at a cost. It may have the cost and not do that.  So if you are considering a Zoned HVAC system,  tell your contractor —  ‘No Bypass Dampers’!  And refer them to this post.

Those Pesky Directions

How many times have you started into a project and had to stop and redo some steps?  How many times have you finished and then realized that you had extra parts?  So what do we do?

Insulation RulerWe go back and read the directions! The manual!  It is so common there are several acronyms for reading the manual.  Directions written by the manufacturer serve several purposes. Some of the cynics around, including myself, realize there is a bit of self promotion and defense in these instructions.  We should also realize that the manufacturer has probably tried to put a few of these together. He may be sharing his wheel with us, so we don’t have to invent it ourselves.

Most importantly, the manufacturer knows how the piece was engineered. The directions take that knowledge and apply it to how the equipment is set up, used or installed. Equipment changes over time. New features are added, materials change and the way it used to be done, is not a good idea.  So, read the manual.

See the attic rafters above. This is the top of a vaulted ceiling, and the insulator has properly placed an insulation ruler.  In a few weeks, blown insulation will be installed and the tech needs to measure how much. The use of the ruler and blowing the insulation level are two of the biggest helps to installing blown attic insulation.  And Yes! They are in the manual!

The choice of this picture isn’t the insulation ruler, it is the nail grid on the ceiling joists. Machine applied in the truss shop, it is fast easy and effective.  Notice the upper right hand corner of the grid.  That is a sharp edge. Be careful, it will cut things.  Hands, pants, shoe tops. Yes! All of those and don’t ask me how I know that!  My wife makes me carry a first aid kit with lots of bandaids for a reason.Duct 1

The house I finished a rating on yesterday had these nail grids on the floor trusses between the basement and the main floor. It also had the HVAC Ducts run between and through the trusses.  The contractor on this job uses sheet metal supply plenums and take offs. He uses the flex duct to form the return air side of his duct system. Yes!  Flex duct gets torn also. Especially with a nail grid.

Two weeks ago, I tested this home. The duct system was very leaky.  According to the Quality Installation Verification Standard written by the Air Conditioning Contractors of America, it was leaking 100%. Wow!  I’ve tested this contractors work before. He always does better than this.  So I ran the test again. Checked my set up.  No change. So I called him.  Shon came right out.  He looked over the system and immediately saw a couple of problems. Including this section of flex duct.

ZeroNow, two weeks later, his crew has reworked their ducts. I’m back to test it again.  I run the same test and scratch my head.  What leakage –  I can get the readings right. The picture left shows no air flow, on the right side, and a very low pressure difference, on the left side of my manometer.  The procedure is to have the Blower Door depressurized the house. Then you depressurized the duct system with the duct blaster to equalize the pressure.  When the pressure difference comes down to Zero, you read the leakage to the outside of the house.

So I checked my set up and tested again. Still no readings.  So ….   I read the manual.  In this case a Field Guide from the Quality Folks at my RESNET Provider and The Energy Conservatory that makes my equipment. I read it twice.  Then it hit me.  This line: Check the duct pressure. A negative duct pressure indicates leakage to the outside. If the duct pressure measure Zero with the Blower Door running, then the leakage to outside is Zero CFM.

As you can guess, the leaks when I tested two week previous prevented this result. What changed?  The crew had found a small tear in the flex from one of the nail grids. Did you see it in the picture up above?  I can see it because I know it is there.  So I enhanced the image and that one is posted below.  To get around all the reflections of the silver colored coating, I placed a piece of white plastic inside the flex so the hole would show.Duct 2

So reading those pesky directions on a test that I routinely run, gets me the right answer. What about the Heating and Air Contractor.  Shon does good work on his jobs, because he follows the professional guidelines and tests his work.  In this case he knew the test, he knew what it meant and immediately saw how to fix it.  What would have been the result if this basement had been finished out and then he had to remove drywall to fix it?

Why is ZERO duct leakage to the outside important?  I don’t want to pay money to heat or cool the outside. If your ducts leak very much to the outside or don’t distribute the air properly, then you are spending more than you need to.  Installing ducts with no leakage to the outside in a new home is an easy process for the contractor. It give the home owner a much better value.

DuctLeak2 copyYes!  I have found duct leakage behind drywall also.  Here is an infrared image of a finished basement ceiling. The homeowners complaint is there is no air flow into his bedroom and it is cold in the winter and hot in the summer. To get this image I turned the furnace up to about 80° F. It was usually about 73° F.  I stretched out on the basement floor and waiting for the heat from the furnace to leak into the cavity between the main floor and the basement ceiling.  In a couple of minutes I had heat patterns showing.  You can see where the duct is running up and down next to the floor joist. Interesting heat spot to the right next to the other joist. Also across the joist and over to the left joist. So we are seeing the duct and hot spots on each side 16 inches away.  Lots of lost heat not getting into his bedroom.

The home with the infrared picture had the leaks on the supply side of the duct system. The one I tested yesterday had the leaks fixed on the return side. I could not have tested with the infrared in the same way yesterday.

So, on this Independence Day, we celebrate!  We celebrate our freedom to be in a business we love, where we can do some good, and make a difference.  And yes, where we can make a living for our families.  We also celebrate the freedom to know our job, to continue to learn as things change and to utilize our professional standards to keep our customers happy and satisfied.

Have a Safe and Happy 4th of July!

Credits:  Photos, myself.  Insulation Ruler –  Northstar Comfort Systems Install.  Duct system install tested yesterday with no leakage to the outside — Shon Peterman and Midwest Mechanical.  The audit providing the infrared image, my customer Craig. The new home tested yesterday courtesy of Sharon and Wade Wilkinson of GJ Gardner Homes. It is in Fontana.

 

Fresh Air, Your Home, Your Health

It has been said over the years that houses need to breathe.

One of the first times that came up, according to Bill Rose in ‘Water in Buildings’ was during the 1930’s. It had become an argument between the house painters and those pesky Energy Efficiency Folks that were beginning to install insulation in the walls of homes. The 1930’s found our country in the middle of the Great Depression and who could blame folks for trying to save a few bucks! The painters were having problem with their paint peeling.  So they started refusing to paint houses with this new fangled insulation.  If you haven’t heard, insulation in the 1930’s was not new.

John PooleAs an Energy Auditor, I have audited some old houses.  This past year, I did one that was build in 1912 – 100 years old! And a beautiful 1887, two and a half story Victorian. My friend John (on the left)  from Derby, CT works on old houses. He has found insulation in houses that are older than any houses than I’ve worked on. People have lived around Derby CT, for a few years longer than they have Derby, KS. John really likes his old homes.  He would tell you that one built in 1887 is still somewhat new.  His current project is reported to have been built in 1700, or it may have been 1667.  He is still trying to figure that one out. In some of his old homes, he has found original insulation. He is not sure about the R-Value.  That of course would depend on how well it was installed.  What were they using way back then for insulation?  Good question!  Since Derby, CT is near the Atlantic Ocean, they were using Seaweed!  An original all natural insulation! And, if it got wet, it doesn’t mold!

So the painters were slightly behind the times in refusing to paint houses with that new fangled insulation in them. They thought the insulation was stopping air from moving into the house. And that was causing the paint to peel. Actually, the insulation was not stopping the air movement in or out of the house. You can buy furnace filters made of fiberglass as you can find fiberglass insulation.

I think the phrase ‘houses need to breathe’ is somewhat misleading at best. It is the things we all cherish in our homes need fresh clean air.  So somehow, we who operate the building, we call home, need to make provision for a proper amount of fresh air.

hallway Yes, air can come in when you go in and out the door. Maybe the question is, where is your door.  Does it go to a hall way in a high rise apartment building?  How about the attached garage?  What kind of fresh air might that be?  Can you open a window? Yes – many of us do!  Is that enough fresh air? Do you do it every day? Is it really fresh air?

What about your window?  My bathroom window opens. When I do open it, and the dryer is running, the dryer exhaust comes right in?  How about that dryer sheet smell and the moisture and the lint?  Got a swimming pool, or several water features in your yard? What about living near a large pond, lakeside or near a creek or river? The higher humidity in these areas can actually be measured and can get trapped near the soffit of a nearby home. Is that part of your fresh air?

1 Inch HoleIf you don’t make the plan of where and how much fresh air your home brings in, who does make the plan?  My guess is everyone does! Fresh air moves into your home, where it can find a hole. Since most attics are vented, they can provide a hole, then the electrician just drills his one inch hole and puts the half inch wire through it! And you have a hole. The plumber runs a sewer stack up the wall and out the roof. Did he seal around his stack? What about the furnace tech?  He runs a flue up through that attic, or out the rim joist. You can add Larry The Cable Guy, the IT Tech running Cat 5 cable, and the list keeps on going!

You choice now is:

  • Allow the fresh air needed by that which you cherish to come into your home any ol’ way someone lets it!
  • Seal all those accidental unplanned air movement pathways and decide for your self and those you cherish where and how much fresh air to bring in.

Midwest AHSI Pro Home Inspectors Meeting

I have been attending the meetings of this group for about a year.  They meet every other month for dinner and a short program.  I’ve learned a lot from the group.  Information from the programs has helped with my Home Energy Audits.  I learned some things last night as well.

The Program was presented by Kerry Parham.  He has completed home inspections since 1978 and is a state licensed Geologist. He has been a home builder and a licensed General Contractor. His inspection company is “Terra Inspections, Inc” of Wichita.

He showed several pictures of roof damage, to new and existing roofs.  Some serious damage was found after he had been told the roof had been checked.

Most interesting were the pictures of electrical panels with Ground and Neutral problems. Several with his Clamp Meter showing current flowing to ground. Talk about high electric bills!  Makes a good case for proper monitoring of your electric bill on  a regular basis.

The pictures that were very similar to what I run into were about HVAC units. He showed several units that were installed in new and existing construction. There was no way they could operate and provide heat or a/c. I have found the same thing. From their reactions, the other inspectors in the audience had similar experiences.

Some of his pictures were from “Flips” and they became slightly scary, with some of the fixes.  Some of his stories were the result of well intentioned homeowners trying to fix a problem without the proper knowledge. Electrical, plumbing were two common ones, also attempted repairs to water leakage.

I also appreciated the pictures of replacement siding installed over obvious rotted exterior walls.

Thank You for the great information.  I always learn something from this group.

A Home Energy Audit — The Value

There is lots of discussion about Home Energy Audits. Utility companies may be providing them to their customers. You can find sources locally and nationally to provide you with one. There are sources online, and several outfits that will sell you a kit to ‘Do It Yourself’!   What should you expect from and audit? Is it worth the expense? Today’s post covers one audit and the results.

A homeowner called wanting to get a handle his old drafty 2 story all brick home.  He thought insulation in the un-insulated walls would help with heat and with the drafts.   He also wanted to know what else might work, and he was interested in how quickly any investment in his home might be recovered with savings from heat or cooling bills.

My visit revealed a nicely maintained home, with minimal energy efficiency beyond the current building practice of 90 years. There had been a few things done in the 1930’s and in the 1980’s that helped.

In discussing the concerns of the family, it was clear they liked their home very much. They had lived there long enough that through re-decorating, gardening and life – it was their home. Comfort issues were not the first concern. There big question was ‘what can we do to save some money?’.  In discussing that, the living room was mentioned as the room that was hot in the summer and cold in the winter.

The audit visit collected data from observation, my tape measure, some pictures.  I looked up in the attic, down in the basement as well as out and around. The furnace, AC and water heater were inspected. The manufacturer had issued a ‘Heat Rise” specification, so testing for that was part of the audit. There was a conventional water heater, and we did a ‘Worst Case Combustion Air Zone” test.

Finally, we would use a Blower Door and an Infrared Camera to measure and locate the potential drafts.

I found some insulation in the attic spaces, and confirmed the homeowners concern of un-insulated walls.

The furnace was within specifications heat rise.  The Worst Case Combustion Air Zone test passed.  The details on these tests and their meaning for a homeowner will be the subject of future posts.

We ran the Blower Door Test.  This test allows us to simulate a 20 mph wind on all 4 sides of the home and the ceiling at the same time. After running the test, standardizing the numbers for temperature difference, and accuracy; the house tested with a Natural Air Exchange at 1.3 times per hour.  The recommend rate without any type of added ventilation is 0.35 times per hour.

With the data collected, a computer model of the energy use in this house was created.  This showed insulating the basement would return the cost in about 5 years. Sealing the leaks revealed by the blower door test would pay off in about 10 years. The leaks were in the basement near the 1st floor; between 1st and 2nd floors and at the ceiling of 2nd floor or 1st floor where it was attic above.

Increasing the R-15 to R-60 in the attic would take 11 years to pay off. Improving a wall on the 2nd floor between a hall and the attic about 20 years to pay off.  And the exterior walls to be insulated would take about 99 years to pay off.  These periods all use the current utility rates, with no price inflation.

The homeowners contacted several contractors to obtain actual prices on the various improvements.  They chose to do some air sealing, insulate the basement walls, the attic, and the wall between the hall and the attic, and to install a new furnace and air conditioner.

After the work was complete, I returned to do a verification audit of the work. The new Blower Door test showed the planned 25% reduction was reached.  The HVAC installation included a new return line to the living room, which has reduced the temperature difference, so the room is no longer shut off on warm days in the summer or cold days in the winter.

BeforeBelow are two before and after infrared images. They show the 2nd floor hallway from the same point. The before picture was taken in February about 11:30 am.  This hallway is on the east side of the roof peak.

 

AfterThe after picture is taken in June about 5:00 pm. The February outside temperature was 46 degrees; the June outside temperature was 98 degrees. Both images were taken with the blower door moving air from inside the house to the outside; simulating a windy day.

 

 

The center of the clipped ceiling (diagonal slope) measures  78 degrees  in the before picture. In the after picture it measures 97 degrees.  So the outside temperature of 45 degrees before  work translated to a 33 degree increase passed through the deteriorated insulation.  After work 98 degree outdoor temperature translates to a 0 degree increase passed through the air sealed and new insulation.

If you look closely the air sealing could have been improved. The planned 25% decrease was accomplished.  It would have been nice to exceed the plan.

What good are the results?  The increased insulation is allowing the AC to work a whole lot less!  If the home had a 33 degree increase in June as it did in February – summer in Wichita would have been miserable in that home.  Also when the new furnace was installed the contractor running the new return to the living room, found a old return in the room that had no duct work. So he hooked up to that return grill for less than planned.  The living room is now comfortable.

Will your Home Energy Audit achieve these kind of results?  Perhaps it will!  If you would like to find out – give us a call.  We would be happy to discuss in more detail how your Home Energy Audit would work.

International Code Council Adopts Energy Rating Index Compliance Option into the 2015 International Energy Conservation Code

This was released today!  The NAHB noted the approval through their Twitter Stream @HAHB on Tuesday!  More options to meet the Energy Code!  Great way to provide flexibility for all builders. One more reason for adoption of the 2015 Energy Code in Wichita/Sedgwick County.Factsheet on adding the HERS Index compliance path

TEXT OF ANNOUNCEMENT:
On October 7, 2013, the International Code Council (ICC) voted to incorporate an optional Energy Rating Index compliance path into the International Energy Conservation Code (IECC) at its meeting in Atlantic City.

The ICC action establishes a new voluntary performance compliance path for the 2015 version of the IECC the “Energy Rating Index”.  The Energy Rating Index is a numeric score where “100” is equivalent to the 2006 IECC and “0” is equivalent to a net-zero energy home.  The current HERS Index Score is compatible to the Energy Rating Index requirements.  This means a builder can use a HERS rating to comply with the 2015 IECC.

The adopted new performance path also requires that a builder must meet the mandatory envelope requirements of the 2009 IECC.

The rating scores that were adopted by the IECC are:

Regions 1 and 2               52
Region 3                           51
Region 4                           54
Region 5                           55
Region 6                           54
Region 7 and 8                53

The new compliance path was proposed by the Natural Resources Defense Council, Institute of Market Transformation and the Britt/Makela Group.

RESNET backed an amendment that represented a compromise on higher rating scores that was reached between the Leading Builders of America and the cosponsors.  This amendment, however, was defeated.

RESNET Executed Director Steve Baden lauded the ICC’s action as a “victory for consumers and builders.  Homes complying through this path will be higher performing hence having lower utility bills while at the same time provides more flexibility to builders in meeting the code.  The action is also a big step for RESNET and the HERS industry.  With this new responsibility RESNET has to step up its game and make a concentrated effort to ensure consistent and accurate HERS Index Scores.”

Much appreciation must be expressed to our partners for their effective leadership.  Without the leadership of the by the Natural Resources Defense Council, Leading Builders of America, Institute of Market Transformation and the Brill/Makela Group this would not have been possible.  Support from the National Home Builders Association, North American Insulation Manufacturers Association, DOW, Green Building Coalition and the Southwest Energy Efficiency Program was critical as well as the more than 150 RESNET member companies and organizations added their voices in support of this effort.

What Tools do you carry in your Tool kit?

I have all sorts of small items in mine; a list would include flashlight,  screwdriver, hammer, tape measures, wrenches, my blower door and infrared imaging camera.  Plus a bunch of flashlights. Yep!  A bunch of flashlights.  I like those everywhere, usually two at a time.flashlights

What kind of tools do you carry?

furnaceAn HVAC Tech might have the first part of my list, and a set of pressure gauges and thermometers instead of my specialized equipment.  Yes, I don’t really need his specialized equipment.

An Install Tech for an Insulation Company would probably have the general stuff and some specialized tools like an insulation blower, staple guns, and an air compressor.

Yes, the work you do requires certain tools. Most tools are fairly general and found in almost everyone’s tool kit, some are specialized to the work we do.

Now that I have pointed out the obvious, everyone maybe wondering why I’m thinking about tools and home performance. So lets connect the dots a little.

First, what happens if you get to the job and you can’t find a screw driver?  It has happened to me more than once!  I just hate that!  How many knife blades have we broken on our pocket knives when we find ourselves in that position?  We still have a job to do and the wrong tool takes longer, sometimes with banged knuckles.

What happens when the products or services we provide to our customers, can perhaps meet their need, like the blade on a pocket knife, but do not meet the need like a screwdriver?  That is the position many in the building performance are find themselves in.  They have a customer that is uncomfortable in their own home or a business with uncomfortable employees and customers.  How does the management design a solution for their techs to implement and thus satisfy their customer, making them comfortable again.  As a business, we each try to provide the solution to the customer from our stock.  That is how we get paid. You don’t pay the mechanic that fixes your car, when the plumbing needs to be fixed.  You pay the plumber, after the drain works again.

So you have a room that is Hot in the Summer and Cold in the winter?  Who do you call and what solution do the problem do you implement?Insulation Blown

If you call a Heating / Cooling contractor, they have equipment on the shelf, probably not insulation. So you will have a proposal to change your equipment for bigger units or perhaps to add a unit. The proposal will certainly involve equipment.  After all, if your mid size car gets you to the store, a larger car will get you there with more comfort.  Would you expect your HVAC contractor to recommend insulation?

What is the actual answer to to your comfort situation? Larger equipment with more punch or some insulation?  What if your solution does not involve either equipment or insulation?

Now we are back to the tools of our Trades!  What tools do you have?  Equipment, Insulation, Air Sealing, Windows?  The solutions you provide must involve the tools of your trade. That is why a savvy homeowner might consult with more than one contractor.  That is a great argument for savvy contractors to partner with contractors and others that work on changing the energy use in your home or business. Why should a good contractor limit themselves to providing only part of the solution.

Air SealingThis is happening in many areas of the country.  Contractors are partnering with others in their area to build home performance teams. There are contractors in Wichita that are moving in this direction.  I think that is great!

Deciding on the measures that will solve your comfort concerns, while bringing down your energy costs, involves a team that includes all of the contractors and a Energy Specialist that does not have a product on the shelf to sell you. The ability to recommend, without having a financial interest in the products, has been valued by many home owners. An Audit by Efficient Energy Savers, provides you with the independence in evaluation, and recommendations needed to get the answer you are actually looking for.

 

Some Results from Energy Improvements

When doing a Home Energy Audit, I always tell people that what I find is not good or bad. I tell them that what I can recommend for improvement depends on  the cost of their Utility Bills.

If you have a water leak, we all know that paying the price to a plumber to fix it, will cost us when the plumber comes. We also know if we don’t fix it, we can pay the water company that amount over 1 or 2 or 6 months. How long depends on the amount of the leak and the cost from the Utility for your water. And then we still have to pay the plumber. so we make a choice.

Blowing insulation into the walls!

Blowing insulation into the walls!

Wendy stuffing insulation into the hopper!

Wendy stuffing insulation into the hopper!

Some choices are easy, for improving the efficiency of a home.  Most homes with a tank type hot water heater inside the home, in a balanced or cooling climate (south of the Kansas / Oklahoma border) will benefit from installing a water heater insulating blanket.  They cost about $25.00 and typical savings just north of the above line can run from 6 – 8 dollars per year. So at $6 bucks a year, the blanket pays for itself in about 4 years. And most people can afford $25.00.

Other choices are somewhat tougher.  Instead of $25.00 to invest in the improvement, cost can run $2,000 to insulate a basement.  If you spend time down there, you know it is a little colder in both the winter (brrr) and the summer (nice), then upstairs.  Again, using some Wichita area numbers a homeowner could save in the area of $350 per year. Each house is different, so I am using some averages from various audits. If you apply this  savings over 6 years, the insulation is paid for and you still save the money. The hitch? It is harder to come up with $2,000 instead of $25.00.

In 2011, I had an Energy Efficiency Project approved under the Efficiency Kansas Program. They loaned some cost, I paid some costs and we added some (a bunch) of insulation, air sealing to cut the infiltration, replaced a 18 year old furnace and air conditioner. I also added an Energy Recovery Ventilator.

Wade in the attic! Fixing a dropped soffit in the kitchen! You can see the 3:12 pitch on my roof.

Wade in the attic! Fixing a dropped soffit in the kitchen! You can see the 3:12 pitch on my roof.

My payment over the 15 year loan is 870 per year, due monthly on my Utility Bill.  So the question is, how did I do with saving some money?  I have been tracking my Natural Gas and Electric billings, with numbers going back to 2009. When I changed HVAC systems, I went to an electric Heat Pump with a gas furnace for back up or emergency heat. As a result, my gas bill dropped and the electric bill, which includes the loan repayment amount is higher than I can remember.

To account for the change, I had to do something with the natural gas, billed in MCF (1,000 cubic feet) and the electricity, billed in KWH (kilowatt-hours).  I decided to convert the gas usage to KWH for ease in comparing before and after.  I also wanted to be able to compare usage against the weather.  Some summers are hotter than others and some winters are warmer then others.

The National Weather Service tracks our weather very well.  You can get an F-6 Report from most airports around the country. In Wichita, we have a choice of 3.  There is Mid-Continent, the primary commercial airport; there is Jabara Airport, a smaller facility that specializes in private airplanes.  And we have McConnell AFB.  All have weather observations and reporting.

The F6 NOAA Report for March, 2011 at ICT. The 2 columns between the red lines show the HDD and CDD.

The F6 NOAA Report for March, 2011 at ICT. The 2 columns between the red lines show the HDD and CDD.

How did I compare the before and after?   Excel works great for prototyping number crunching and charting the results.  I collected my data on usage, cost and Degree Days from the Weather Service.  I built two charts. First one covering January 2009 through present. After looking at this chart, I built another showing January 2011 through present.

The charts show three (3) lines. The Blue Line represents Heating Intensity by month.  I took Heating Degree days, multiplying by 5.  The Red Line represents Cooling Intensity by month. I took Cooling Degree days, multiplying by 3.5.  The Green line represents Energy, show in KWH.  I converted my gas usage to KWH by ” MCF x 293 “. Then I added the KWH from Electric and Gas to chart the Green Line.4 years

2009              2010                     2011                  2012                 2013

If you look at the top peaks of the Blue Line – you see the cold months. Imagine a level line averaging those tops. Somewhere between 4000 and 5000 on the Y-Axis. Look at the Red Line Peaks – you see the hot months. Imagine a level line on the Average of those peaks, just a little over the 2000 on the Y-Axis.

Now look at the Green Line, it goes up in the winter, and summer, down in the spring and the fall. This line doesn’t really run level on the peaks. If you pick about 6500 on the Y Axis in 2009 and 2500 in 2013, the line slopes down.  The Red vertical line shows when the improvements were made. This chart shows 3 years prior to the date of improvements and 1 year after.

The Chart below just shows one year before and 1 year after.  So the horizontal spreads out a little. I think the point is made in either chart.  The improvements require less energy to be purchased.

How much less in dollars, instead of Energy Usage? I’m saving my 870 annual repayment amount plus enough to repay myself over 15 years for what I kicked in.  And a little extra.

2 years

2011                                    2012                                   2013

Some one will ask why did I adjust the HDD and CDD numbers.  I did it to match the scales on the charts.  I first set it up with direct numbers. When you looked at the chart you could not make out any significant ups or downs to compare. So I reworked the numbers with multipliers, to make the charted numbers line up better.

In September, 2011 the chart shows 155 HDD, 591 CDD, the energy usage in KWH is 2261.  In September, 2012 the chart shows 0 HDD, 960 CDD with 1217 KWH used. Using the same Y-axis scale required some changes. So I used a multiplier to move from direct Degree Days for Heating and Cooling to an intensity measure for heating and cooling.

Thanks for following along.  I will make another post with more of this story.

Build Your Own Home Energy Audit

A comprehensive Home Energy Audit takes time and covers a number of areas. It provides lots of information and recommendations.  A homeowner may choose to limit the inspection to those items of their concern.

The energy efficiency of each home combines an analysis of the components of the home and how well they are installed.  Think of a bucket of water, the bucket is the walls and ceiling of your home. A pinhole in the bucket will drain the water from the bucket and the heat from your home!

A Home Energy Audit looks at the ability of each building component to resist the transfer of heat. The air tightness of each component is also reviewed.

This post covers a description of each part of a comprehensive Home Energy Audit.

Pricing, previously contained in this post, is posted separately.

Utility Analysis

The actual usage over the last 12 months of Electric and Gas is compared to the home size and evaluated. This requires information from the Utility Companies.

Infiltration Testing                 

(Multi-point Blower Door Testing with Thermal Imaging and Indoor Air Quality Analysis)

Everyone has felt a cold draft at one time or another. Since the air blew in and the house didn’t pop like an overfilled balloon, the air blew out somewhere else.  This test simulates a 20 MPH wind on all four sides of the home at the same time. It allows an actual measurement of leakage and it identifies the leaks. This allows a specific plan for the leaks in your home to be fixed.

The recommendations will include effective measures to improve indoor air quality, not just install what the salesman has in-stock. If you have de-humidifiers running this Testing is important.

Ceiling Evaluation:

The ceiling and attic areas are examined for insulation, ventilation and thermal bypasses. This is done from the outside of the home, the inside in all rooms and from the attic. It may involve remote camera usage. If Infiltration Testing is part of the package, information from the Thermal Imaging portions are applied to the ceiling Evaluation.

Foundation Wall Evaluation (below grade):        

In most homes a major source of heat loss is from the crawl space, the slab or the basement walls. There are generically referred to as the foundation of your home. Traditionally, builders have confused the thermodynamic principles involved, with hot air rising and heat loss, to falsely assume that basements cannot be kept warm.

Wall Evaluation (above grade):

Homes over twenty years old, or homes with a major insulation failure may benefit from a specific wall evaluation for walls above grade.  It is part of a comprehensive  energy audit. All wall evaluations are conducted with Non-Destructive-Test Methods to start. Depending on the home, the type of construction, access to various areas, further testing that involves minor holes being drilled will be discussed with and approved by the homeowner before the end of the evaluation.

The condition and energy efficiency of your exterior siding is done at this point.            

Equipment (furn. AC, hot water):                    (Includes safety checks on Gas Fired Equipment)

Your heating and cooling equipment is a large investment. What are the efficiency ratings on your existing equipment and what is available on the market? How does a home owner sort out fact from sales pitch.  This inspection includes safety testing for gas fired equipment. Furnace, Heat Pump, AC, Hybrid Heat Pump, are included.

Windows and Door Evaluation:           

Windows are advertised everywhere.  On the Radio, TV, the newspapers and other print media all carry large volumes of sales pitch for replacement windows. The FTC has fined some window companies for outlandish claims on energy savings.

Are your windows an energy problem? Can those energy problems be fixed or should the windows be replaced? What is the best for my home?  Low E, argon filled, double pane, triple pane? How does a double pane window save energy?  All these questions and more are answered. And you get the answers from someone that does not have a financial interest in your purchase or non-purchase of a product.

Windows and Doors are both holes in the wall.  From an energy loss standpoint there is not much difference. Doors are not as heavily advertised, but they are pushed after the salesman gets to quote your home.          

Computer Modeling and Reporting

The Comprehensive Home Energy Audit provides a complete energy usage model and reporting of problems, recommendations and solutions. Interactions between building components are considered in the computer model. You can go from the report to soliciting firm prices from a contractor or doing it yourself with this report. This reporting will qualify for applying for and Energy Improvement Mortgage if you are buying a home, or refinancing your current home.

If you choose various parts of the Home Energy Audit, written reports and recommendations will also be provided. These will all you can go from the report to soliciting firm prices from a contractor or doing it yourself with this report. The reports are limited to the selections made. Interactions between building components are not considered.

Duct Leakage Testing Not included in the comprehensive audit.

Some comfort and energy loss issues involve improperly installed ductwork. Testing is easy. Fixing these problems can vary in complexity depending on the home.      

Lighting and Appliances Not included in the comprehensive audit.

Incandescent, halogen, CFLs, LEDs, which is best for your home?  Not every fixture needs a high efficiency light! Should I get a new fridge or other appliance?  All these are part of the Lights and Appliances.

Bonus Room (over the garage, or in the attic) Included in the comprehensive audit.

Rooms placed over a garage or in the attic are a special case. They are part of a comprehensive audit. They can be an individual item, with infiltration testing, due to the unique construction problems with them.

For more information or to schedule a Home Energy Audit:  

V / T  316 641-5258  or  email:  info@efficientenergysavers.com

You have an Energy Star New Home – How accurate are the Projections?

This study is of interest to all HVAC, Insulation Contractors. It is also important to Home Owners.  An Energy Audit makes recommendations and projects cost effectiveness based on a computer model of the Energy Use in each specific home.

How much can you count on those projections? Home Energy Usage depends on three things!

  • First:  The Weather!
  • Second: The Lifestyle of the Family in the Home!
  • Third: The construction of the Home!

Mother Nature has control of the weather! Lifestyle is the difference between having 3 High School Football Players in the family, or 3 High School Cheerleaders.  Energy use will be different. Then what happens to the use when those kids go off to college.

This study actually compares the projections from several hundreds of thousands of homes to their actual usage.  You can read the RESNET Summary. You can read the report itself. I have reprinted the Summary with the link to the Report below.

The original Summary can be read here.

My conclusions:

  • The correlation from projected usage to measured usage over time justifies the reliance on computer modeling using the software to guide your decisions on prioritizing improvements in energy efficiency to your existing home.
  • The correlation of projections for Energy Star New Homes to actual usage gives Builders, Contractors and Home Buyers the confidence to use an Energy Star New Home Certification for lowering the ongoing Operating Costs for Energy in a New Home Purchase.

John Nicholas

 

PROJECTIONS FROM HERS ACCURATE August 22nd, 2012

Posted by RESNET under RESNET News

Over the years, there have been discussions over how accurate are home energy ratings in predicting the energy use of rated homes. To enhance the discussion of the accuracy of home energy ratings’ energy use projections it would be good to review a study conducted and published by Advanced Energy on a large set of homes in Houston, Texas. The authors of the study were Michael Blasnik of M. Blasnik & Associates and Shaun Hassel and Benjamin Hannas of Advanced Energy. The objective of the U.S. Environmental Protection Agency supported “Houston Energy Efficiency Study” was to assess the actual energy use of groups of homes built to different energy efficiency specifications in Metropolitan Houston – typical non-program (baseline) homes, ENERGY STAR® homes labeled by a Home Energy Rating and guaranteed performance homes.

More than 226,000 homes built from 2002 through 2007 by dozens of different production builders were included in this study. The large dataset also provided the opportunity to analyze how certain construction characteristics are related to actual energy usage. Data collected for this project included billing data for all new homes built in the CenterPoint utility service territory from 2002 through 2007, information from property assessor databases of four counties, detailed building characteristics for tens of thousands of ENERGY STAR homes from CenterPoint’s ENERGY STAR Homes tracking database, and detailed data files from energy raters including the home energy rating software tool, REM/Rate, input files and building shell and duct leakage test data. The study did not involve any direct data collection in the field but instead relied upon existing data sources.

This approach allowed the scope of the study to be much larger in terms of the number of homes analyzed but left some gaps in our understanding of some details, especially of baseline homes. The overall dataset includes hundreds of variables for 226,873 homes, including 114,035 potential baseline homes, 106,197 ENERGY STAR homes and 6,641 guaranteed performance homes.

Although consumption differences across groups of homes are smaller than advertised, ENERGY STAR homes perform very close to the predictions of the models on average, while baseline homes perform better than the reference homes defined by the HERS standard. ENERGY STAR uses a base case reference home defined as minimum local code specifications combined with the least efficient cooling, heating and hot water systems available, a leaky building envelope and a poor duct system. Using this yardstick to measure the performance of the ENERGY STAR houses in the study, they did quite well – showing a strong and fairly consistent relationship between actual and projected performance for both heating and cooling. Therefore the apparent lack of savings is attributable not to underperformance by the ENERGY STAR homes but to the fact that the baseline houses in Houston perform considerably better than the ENERGY STAR reference house.

The relationship between REM/Rate cooling load projections and actual electric usage was examined graphically and statistically for 10,258 homes with sufficient data. REM/Rate projected an average cooling load of 5,506 kWh/yr while the billing analysis estimated average cooling loads at 5,677 kWh/yr, about 3 percent higher – excellent overall agreement. Although the analysis found no systematic bias in the REM/rate cooling projections, there was a large amount of variability in the data. Findings revealed that the correlation was higher between house size and cooling load than between REM/Rate projected cooling load and actual usage. However, the study team feels confident in stating that when using current modeling software with energy-efficient new homes, there is a strong and fairly consistent relationship between actual and projected performance using REM/Rate for both heating and cooling. REM/Rate also estimated the average heating usage of program homes fairly well – only 4 percent lower than the measured loads.

To download the study click on Houston Energy Efficiency Study