Category Archives: Ventilation

A Healthy House Part 1c: How Dry is Dry

rainIn Part 1a, we have looked at how your builder builds your home to keep water from the outside from damaging your home.  He used materials to shed the water and he lapped them over each other, from the roof peak and the shingles all the way down to the ground. And then directed the water away from the house, using gutters and sloping the landscape away from the house. Easy, quick and it looks nice.

In Part 1b, we looked at how your builder builds your home on the inside to keep water where you want it, and provide easy clean up when it does get out of the pipes, the sink, tub or shower.

BucketYou can think of this as bulk water.  You can see it, this is water that is usually measured in quarts or gallons, and it is responsible for 50 – 60 % of the water damage that occurs over time. The exact percentage depends on the source doing the figuring.  So why is there a Part 1c?   There is one remaining source of moisture in most homes.  Water Vapor.  Hard to see it, hard to measure it.  The damage water vapor causes is usually found to be very extensive.

If you have a roof leak, it usually ends up inside and you find it while it is relatively small. When it is fixed the damage is limited and fairly easy to fix.  Leaks from plumbing and over flowing sinks and tubs, is usually caught very fast. The surface is easy to clean up and many times contains the water.  Damage from these sources doesn’t really occur unless the water continues over time to get there.  It stays wet and is not allowed to dry out.

Flood type events are not really of concern here. When they happen, the homeowner is aware, his insurance may cover repairs and there are lots of contractors that will do the work. Generally, they have little to do with how the house was built.

teapotWater vapor is present in varying amounts in every home.  What is the relative humidity in the home?  40% – 25% – 65%?  That is water vapor in the air. We add to that from breathing, cooking, and hygiene activities, like showers and running hot water for various purposes.

How do we control this water vapor?

Spot ventilation.  This may be as simple as opening a window next to the stove where the pasta is boiling, or the tea pot is ready to pour. It may be using an exhaust fan over the stove to actually remove the water vapor from cooking out of the house. Same in the shower.

acWhen the heat and humidity arrive around here, in the summer, it is air-conditioning season. Most air conditioners will lower the temperature of the air and remove some of the humidity at the same time.  Somedays they do a great job, somedays the ac unit really has to work and it.  Occasionally, you will find a unit that makes the room fairly cold, and you just feel clammy.  Like you just walked in from 100° outside and you are wet all over. The trouble is, it doesn’t go away.  You keep feeling cold and clammy.

That is the first way that water vapor causes a problem with our homes, it makes us uncomfortable.

How does the water vapor move into the walls and attic to cause problems like the liquid or bulk water we looked at?  It has two ways to move.  Air Movement and Vapor Diffusion.

Vapor Diffusion involves moving a vapor, in this case water.  It involves temperature and pressure.  It also involves Math, lots of fancy math.  I know some math teachers that can run these numbers, and a couple of physicists here in Kansas.  I’m sure the characters on TV’s ‘Big Bang Theory’ could run the numbers.

Adding MachineThe good news is, we don’t have to run the numbers.  If you take a room in your home with the humidity at 40% and 70° –  you will find less than a gallon of actual water.  By the time all the numbers are done, the answer is:  Yes – Vapor Diffusion put some of that water vapor into the wall.  And we can test that the 7% moisture content of the drywall, studs and other parts of the wall, is now 7.5 or 8%.  Not much change.   If you have read much on this blog, you know I lower my blood pressure by turning wood, into bowls.  Anything less than 12% moisture content in wood is considered dry.

If the builder bought kiln dried lumber, and kept the rain off it, while the house was built, the wood is probably 8 – 9 % moisture content when the home is finished.  Kiln dried lumber is typically 6 – 8 %.  Moving from an enclosed type shed to the job site, wood will pick up a little moisture.

What about air movement and water vapor?  That is the one to take care of.  Uncontrolled air movement takes the water vapor right along with it. When that vapor comes in contact with a surface that is below the current dew point, it will condense and the liquid wets the material.  We know that energy savings is easy to obtain with air sealing.  So fixing the air leaks is good for stopping the water vapor from making our house wet also.   How much?  This graphic from the guys at Building Science Corporation shows how much.

Air_Vapor

This post is part of a series of posts on A Healthy Home.

A Healthy Home

Healthy HomeBuilding a new home, gives the homebuyer an opportunity to build in all the things they want. The floor plan, bedroom arrangement, windows are all important.

Also right up there is a house that is healthy. Everywhere you look, someone is pitching, this is healthy for you.  We have lots of buzz words for healthy.  Organic, whole grain, anti-oxidant, reduced fat, low sugar, wellness, all-natural are but a few. How do you make a house into a healthy home?  It starts with design and a few simple objectives.   Ideally, a healthy home is:

  • Dry
  • Clean
  • Well Ventilated
  • Combustion by-product free
  • Pest Free
  • Chemical Care
  • Comfortable
  • Safe

read beforeIt seems fairly simple.  We want a roof over our head to keep the elements out.  Hot or cold, rain or snow, we don’t want them in our home.  The dry home starts with a well constructed roof.  That keeps the weather related water like rain or snow out. Then the walls, and the foundation.

Clean may be obvious, or not. Well Ventilated and Combustion by-product free, along with pest free, no toxic chemicals, comfortable and safe seem also to be obvious.  There is a saying about the Devil being in the details.  It is certainly that way in building a home. So a few details on these topics that make up a Healthy Home are important.

I will be posting a series based on the Healthy Home. We will take a look at each of the points listed above and what they mean to the home owner.

Part Ia   How Dry is Dry       Bulk Water from Precipitation

Part 1b  How Dry is Dry       Bulk Water From other Sources

Part 1c  How Dry is Dry       Water Vapor

Part II    The Home Starts Out Clean

Part 3    Well Ventilated

Part 4     Free of Combustion Byproducts

Part 5     Pest Free

Part 6     Chemical Care

Private HERS Rated Homes

During 2013, New Home Builders in the US placed a HERS Rating on over 50% of the new homes built. Builders in most large housing markets have found that a HERS Rated Home sells faster than one that is not Rated.

Is the new home builder the only one that can place a rating on a home?  Actually anyone with an interest in the home can have a HERS Rating completed. The process is the same as when the builder completes the process.

Tonight a new home is on the page listing ‘Actual HERS Rated Homes’ .  This home is one the owner chose to have the HERS Rating completed.  It is being built in Derby, and is listed as Sold Projected. This home was planned to be lower than the standard new home. It is projected with an INDEX of 86.  It will come in lower.  The projected HERS process took into consideration the plan and the levels of insulation and equipment the owner and the builder have decided on.

HERS Rated Homes

HERS Rated Homes

The reports also show how much energy will be used in both heating seasons and cooling seasons by this home.  Several recommendations for cost effective improvements were made.  Several were based on simply lowering the annual utility bills of the home.  When the builder gets pricing for these improvements, the home buyer can make a good decision to proceed with that improvement or not.

Several of the additional insulation recommendations fall into this category. Several of these improvements were based on improving the comfort and Indoor air quality of the home. Again, when the builder has prices in hand the home buyer can make good decisions about these health and safety items. These items include improved equipment, and improved mechanical ventilation over the code required fresh air duct into the furnace.

Yes, there is no code adopted and enforced in the Wichita area requiring insulation in a new home. There is a code item that requires fresh air to be brought in. I have yet to see a new home without provision for a dryer and spot ventilation fans in the bathrooms. The fresh air is needed to compensate for these items.  If it is not provided, these fans will cause fresh air to come in where it can, not where you want.

When think of  a Heating and Air contractor, you have seen them referred to as HVAC Contractors.  The V is for Ventilation.

Remember to ask your Builder for the HERS Rating when you look at a new home. If the builder isn’t Rating his homes, you can obtain a HERS Rating for your favorite model.

Carbon Monoxide and Your Garage

I am studying ‘The Residential Ventilation Handbook’ by Paul Raymer. Mr Raymer has worked with residential ventilation, design, consulting, teaching for over 30 years.

I just reached the Chapter on Garages. I’ve known for several years the potential problems with an attached garage. Two years ago, I did some recommended work in my garage because of these issues. I carefully sealed the wall between the garage and the house, and I installed a mechanical ventilation fan.

lawnChemWhy is the attached garage important to the Indoor Air Quality in your home? OK! What is in your garage? Mostly stuff you don’t want in the house. Like fertilizer, bug spray, weed killer, gas for the lawn mower. Cars, and other vehicles are usually there also.

Mr Raymer includes a table of Carbon Monoxide levels and comments or the potential for harm to people. I knew some of these, and others I did not. Carbon Monoxide is a colorless, odorless gas that is a byproduct of burning fossil fuels, like gasoline, natural gas, or propane. Carbon Monoxide (CO) is measured in parts per million (PPM)

Here are some entries from the table:

1-2 PPM Normal from gas range, traffic etc.

9 PPM Maximum Allowable Level for 8 hour period in any 12 month period. EPA and ASHRAE. Normal after using an unvented gas oven.

15 – 20 PPM Impaired performance in time discrimination and shorted time to angina response

30 PPM UL standard that detectors not sound an alarm unless exposure is continuous for 30 days.

35 PPM Maximum allowable outdoor concentration for any one-hour period within a 12 month period. EPA – ASHRAE

50 PPM Maximum allowable 8 hour work exposure (OSHA)

150 PPM UL Listed detectors must sound full alarm between 10 – 50 minutes of exposure.

500 PPM Car started from cold in garage with door open, and allowed to run for two minutes

800 PPM Dizziness, nausea, and convulsions within 45 minutes.

6400 PPM Death in 10 – 15 minutes

70,000 PPM Typical tailpipe exhaust concentrations after cold start during the first minute the engine runs.

NOTE: After running for 17 minutes, these concentrations finally drop to 2 PPM

tailpipeI think the above table is worth serious consideration from every home owner, every father and every mother.

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.

Water Pipes Freezing and Cold Weather is Predicted — What should I do?

When the recent cold snap with below Zero temperatures approached, I had several calls about the potential for freezing pipes and what a homeowner could do.  This blog post has compiled all those answers and some other information for easy access.

Things you should know about your water pipes.

Location:  Where are they?  Interior walls?  Exterior walls?  Typical plumbing runs pipes through the wall to the cabinet under (or behind) the sink, shower or tub.

If it is an interior wall, you have less chance of those pipes freezing, then if they are in an exterior wall.

Location:  Where do the pipes enter your home?  Into a basement?  Into the crawl space? Under your mobile home?

This can be a problem area.

The weather forecast says “Your Water Pipes Might Freeze Tonight! Knowing where your pipes are enables you to take some simple preventative action.

Open the cabinet doors by the pipes on exterior walls.  This allows the warmer air from the room into the cabinet area.  Check to see and remove any cleaners etc that a child or pet might get into.

Open a cold water faucet at the sink and let it drip slightly.  Moving water does not freeze. It doesn’t need to move a lot, just a little.  If you do this you may need to replace the faucet washer later. Small price compared to frozen pipes.

Don’t lower your thermostat temperature.  Bypass any setbacks on the thermostat. The amount of energy will be a minimal cost compared to frozen pipes.

Don’t leave home in the winter for any length of time *and* turn the heat down.

If your water supply comes in through a vented crawl space, close the vents.  Check to see that insulated pipes have intact insulation and that it is not wet.  Wet insulation is worse than no insulation. This also applies to mobile homes.

If your water supply comes in to a basement that is not heated, check as if it were a crawl space.

You get up in the morning and there is no cold water at one sink.

First try the other faucets to see if this is just at the one sink, or perhaps where the pipes come in.

Leave each frozen faucet open.  As the ice begins to melt, the water will begin to move and that is good.  Moving water will melt the ice faster.

How you identify the area where the pipe is frozen may vary, you will find it in an area that feels cold, and it seems logical to you that no heat is getting there.

You will have to search for the frozen section(s) of pipe. You can do this with your hand. If you touch the pipe and it is really cold,  you may be close or there.  Normally, water coming from a pipe that is under ground, will be between 50 and 55 degrees F. You will feel the difference with a frozen section or close to frozen section of pipe at 32 degrees.  You can also use a contact thermometer.

If you find no water at all faucets, then your frozen section is probably at a point of entry to the home. Older homes, prior to the 1940’s, that were built before running water was brought into the home, will have many varied places to look. If you have lived there very long, you probably already know. Otherwise, it will be in a basement or crawl space, or perhaps an exterior wall.  If you live in a home that is built on a concrete slab, your odds of a frozen entry pipe happening are minimal.

To Thaw the frozen section. Use heat!

Use a blower dryer, a heat lamp, some type of portable heater. You can use a towel soaked in very hot water, and wrung out well.

Do *not* use any type of open flame.  Pipes are almost always close to parts of the home that burn, and that is not a good thing.

Second, stay with your heat source and the frozen pipe.  If the pipe starts to leak during the process, you need to know so you can shut off the water.

When you get the pipe section thawed, and you have no breaks or leaks, great! If you get any type of leaking, get it fixed.

Prevention for the next cold snap.

You should follow the simple preventative steps listed earlier.

For a more permanent solution, you need to create a situation where the pipe section that froze is kept warmer. That means you add heat or insulation and stop cold air movement.

Pipe insulation from the big box or the hardware store could help.  Buy the correct size, it comes molded for 1/2, 3/4 and larger pipes.  This is a foam that you can easily compress.  So, fasten it snugly, but not tightly.  It should fit more like a nice sweater on your arm instead of a tight rubber band.  Since it is squeezable, it is open cell foam and will allow air movement through it. So I would wrap it with something to stop the wind. Tape would be easy, but you could use something rigid, like small pieces of plywood. For tape, you could use packing tape, or duck tape.

Depending on the location of the pipe section, some rigid foam, blue or pink board type, might work better. Typically this would be a pipe near an exterior wall, with room to put the insulation between the pipe and the wall.  You can fasten it to the wall.

Most of these will also benefit, and some instances will require additional heat.  So opening a cabinet door is something you might have to continue. Modifying any type of duct work is not recommended for directing heat at this type of problem.

This leaves those section in an unheated basement or a crawlspace.

You could add a heat tape.  Make sure you have easy access to this to turn it off after the cold snap and to turn it back on for the next one.  If you don’t, you will probably leave it on all winter and that is expensive. You also need to carefully check the sizing of any extension cord. If in doubt, hire an electrician to add an outlet, so an extension cord is not needed. Adding this type of fix is also something to keep your eye on and check regularly. It is a Fire Hazard.  I would not recommend a used heat tape.  Buy a new on and replace it annually, until you get a more permanent and safe resolution.

Permanent and Safe Solutions

These require some thought and planning. They may take a contractor to implement. You may find through the planning process, other problems that will be fixed.

Give me a call, if you have frozen pipes and want a permanent solution. I can develop a solution for you. Since I don’t sell the products you might use, I can come up with a solution that works for you! Not one that moves my merchandise.

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.

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.

As 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 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.

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?

hallway

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?

Half Inch WireIf 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.

Ductless Mini Split Heating and Cooling – Is it any good?

I’ve had the concept of a Ductless Mini Split HVAC unit brought up recently. I’m out doing a home energy audit, I’ve been asked on Twitter and in other contexts several times.  A discussion on a Professional Linked In group and my follow up comment has resulted in this post.

First – What is a Ductless Mini-Split?  The simple answer is ‘One type of residential HVAC equipment’.  Other common types of residential equipment are Single Package Unit and a Split Package System. An example of a Mini Split on the right by LG Electronics USA Commercial Air Conditioning. The top image is what you see inside. The bottom two views are of the outside unit. LG is one of many mini-split manufacturers.

If you are building to Energy Star, your HVAC contractor must perform various calculations to figure the size of the units, set up the duct work and select the unit. These calculations are specified by the Air Conditioning Contractors of America (ACCA) an industry trade group. Known as Manuals J (size) D (ducts) N (equipment selection).

If the process and calculations, especially Manual N will show a Ductless Mini Split as fitting the need, great! An example of a Single Package Unit on the right. Outside both summer and winter.

If you are not building the Energy Star – the 2012 recommended Energy Code requires the same process.

If your jurisdiction has not adopted the 2009 or 2012 Energy Code, the prior Residential Mechanical Codes require ACCA calculations or similar. The outside condenser of a Split System on the Left.

Heating and Cooling equipment is routinely oversized in existing homes and in new construction. This approach avoids the math and fits the American image of ‘bigger is better’. It also avoids after hours service calls concerned with the home not heating up or cooling down fast enough.

HVAC equipment, just like your car, operate most efficiently traveling at a constant speed. For your car a highway speed without starting or stopping in city traffic is the efficient speed. Note the Fuel Economy Numbers show the best and the worst MPG figures for each model. At the right is an example of the inside unit of a split system.

Due to the variations in climate from South, with little heating and lots of AC; to the North with a lot of heating and no AC; ACCA uses a design temperature in the calculations. Essentially you can figure the design temperature for your area. The National Weather Service publishes the daily highs, lows and average temperatures for each weather station. The report you want is monthly and is referred to as a J6.

How to figure that is a little much for this post.

A properly designed HVAC unit, like your car will run constantly at or in excess of the design temperature. So these hot summer days, most of us are above the design summer temperature; your AC is OK if it runs all the time. Preventive Maintenance is needed for the HVAC equipment, not sleep.

All that aside; a ductless mini-split is a great choice for a smaller space. My experience with specifying these for Homeowners is that HVAC manufacturers and contractors dearly love them. They are priced accordingly. At the left, the outside duct of a Single Package Unit, typically with no insulation.

 

The Mini Split gets away from the use of ductwork to distribute the conditioned air. That is the strength. Most ductwork in our homes is not designed correctly, it leaks and requires too much fan capacity to distribute the conditioned air. In the right sized space, going without ducts has many advantages.