Look to building science and having a proper assessment performed to help you make the right improvement choices for home comfort in the hot summer months. 

A new HVAC system is likely not the right solution for a cooler home when it is blazing outside!

Temperatures in the attics of Maryland homes during summer months can go as high as 150-160 degrees.  It is a brutal place with stifling air and high amount of humidity. 
 

Healthy Attic  vs. Unhealthy Attic 

When an attic is not properly vented, air sealed and insulated the stagnant hot air and pressure is too much for an old insulation system making summer days at home a drag. 

Add leaky ducts to the situation and it makes for a long, hot summer.
 

Watch how this BPI Certified Pro and Owner of Insulwise in PA
Breaks it Down in this Excellent Animated Video

 

Consider this:

Maryland homeowners that have a minimum insulation level in the attic equal to R-19, reflective roof shingles and proper ventilation can experience up to two-thirds less solar heat gain than those with characteristics such as little to no insulation, dark roofing shingles and no attic ventilation. 

There are five things we recommend to make an impact on your summer comfort.

1. Air Seal Your Attic
2. Insulate Your Attic
3. Seal Your Accessible Ducts 
4. Encapsulate Your Crawl Space
5. Improve Attic Ventilation

 

 1. Air Sealing Your Attic

If you want to know if you should air seal your attic, then you can ask yourself a few basic questions and quickly arrive at the answer. 

The easiest way to know is to determine if you have air sealing in your attic now.  If not, then you definitely need air sealing.

When the hot build up of air in the attic creates pressure then the cracks that are left unsealed are gateways for the heat to enter your home.

If you want to learn much more about air sealing and watch how it is done in different areas of your attic and basement then check out this cool article with demos...

2. Insulate Your Attic

If you are having comfort issues in your home there is no doubt that a good place to start looking for answers is in the attic.  

Maryland attic insulation projects can be better understood and considered with a little effort and knowledge.

To get things going you must identify two main things so use this recent write up as a guide to figuring out if insulation is your next move to beat the Maryland summer heat!

 

 

3. Seal Your Accessible Ducts

When it comes to improving home comfort and energy efficiency it is amazing how little attention is paid to sealing HVAC ducts.  Properly sealing leaky HVAC ducts should be a high priority for energy efficiency and comfort.

According to the EPA and other studies, the HVAC ducts in your home can be leaky enough to account for up to as much as 30% of a household's total energy loss. 

So, what can you do?  Check out this article with great information on next steps you can take to seal your accessible ducts.

 

 

4. Encapsulate Your Crawl Space

Let’s face it – you want nothing to do with your crawl space.  You just assume that it does not exist.  You ignore it.  You board it up, lock it and put it out of your mind! 

But, it keeps reminding you it’s there.  In the summer when you go down to wash the laundry and you get a whiff of that musty odor that only comes out when it is humid. 

A few years ago you poked your head in the crawl space for one reason or another and you noticed several pieces of insulation falling down.

Read this article on what to do with crawl space vents, walls and how to properly seal it up!

 

5. Improve Attic Ventilation

Typically, condensation in the attic starts due to a moisture issue created by introducing two completely different air masses.  A possible issue in summer if the attic is not ventilated properly will certainly contribute to an uncomfortable home.

In hot months a leaking AC HVAC duct in an attic and other HVAC related inefficiency can allow air to seep out and interact with the hot humid attic air, particularly if the attic is not well vented.  This will cause mold and can result in comfort issues.

Read this article to get more insights into how baffles work to ventilate your attic.

 

What next steps can you take if this all makes sense to you, but you are not sure where to start?

You should sign up for a home energy audit...

Through BGE Here

Through Pepco Here

For only $100 through the Home Performance with ENERGY STAR Program - I am qualified to get all of the answers for you!

 

If you are always asking yourself, your spouse, your brother, a friend or just about anyone that will listen...

Why is my energy bill so high all of the time?

Then read this short article for key insights and actionable ways to fix your issue.
 

Three Dimensional Thinking

First, to make a house energy efficient you've got to tighten your building's shell and usually the first thing that comes to mind for most people is windows and doors.  

But, residential energy consultants know there are many other places that need attention due to physics and pressure inside your home, especially at the top and the bottom.

Have you ever noticed at one time or another that a door inside your house is particularly hard to open or that suddenly it slammed shut when otherwise on any other day, it would simply close behind you? 

The takeaway is that there are pressure dynamics going on inside your home and sometimes it is noticeable and other times you have no idea.

So, don't overlook this when asking yourself about your energy bill and use this article to begin the "hunt" for the places that can easily be fixed.  Once discovered, you will have more control over your comfort and the energy bill.

One great cost-effective example that the majority of homes have is some type of attic access panel.  In most cases, these areas are not insulated or sealed properly and they will greatly reduce the overall R-value of the rest of your insulation.

Click to watch treatment to the hatch for ideas about how you can do it at home.
 

Getting Control of Your Home's "Breathing"

How many times have you heard somebody say "a house needs to breathe"?

The "breathing" is the start of your problem.  Yes, we want our homes to "breathe", but we must consider uncontrolled breathing compared to controlled breathing.

Uncontrolled air leakage occurs when air moves through gaps or openings in walls, floors, ceilings, duct work, doors or windows to the outside and is often a major source of energy loss in homes.

Another way to look at this is by considering how we behave on cold winter days.  Most people jump out of their skin when they realize a window was left open and most people will close it right away.

Consider this:

What if all of the holes and gaps around your house are equivalent to three open windows? 

What if you could seal enough of those areas to close two of them? 

This would mean that you have a lot less energy loss and you can still breath!

In today's technologically advanced world, it is not difficult to figure out how much air a house exchanges with the outside on an hourly basis with just a few measurements and blower door test so that properly controlled ventilation can be added if a house gets too tight.

Why Sealing is So Important

For every little bit of conditioned air that leaves through the cracks and crevices around a home it gets replaced with outside, unconditioned air. 

And, that is very costly!

When reviewing information from an energy audit report, the story becomes much clearer in terms of where we must look to be more efficient and it is not because the lights are on too much.  Also of interest, windows and doors account for very little overall leakage when tested.

The green portion of the pie chart is the baseload.  Baseload refers to everyday stuff like lights, computers, fridge, etc. the largest load is the refrigerator so if you are already using ENERGY STAR then there might not be too much more room to save.  Efficient light bulbs will help too.

Next, look at the red and light purple.  Those show the heating and cooling costs.  

Consider the most important thing to understand when it comes to making an impact on heating and cooling usage/ costs:

You can put the world's most efficient HVAC system into a leaky house and get zero results.

In other words, don't put the cart before the horse. 

Sealing up holes, gaps and cracks around the "shell" of a home is a great way to really move the needle and will make any age HVAC system more efficient and seem like brand new. 

Where to Begin Looking for Opportunities

The pressure inside a home is greatest at the top of the building and the bottom of the building so looking in those two places will yield the lowest hanging fruit.

1. Seal Recessed Light Fixtures

The first thing you can do to save energy at home and reduce drafts is seal up you recessed lights in ceilings that are below the attic.  These common fixtures are secret gateways to the attic which means energy loss and comfort challenges. 

Most older recessed lights have ventilation holes so that heat from the bulb can escape.  Energy customers with recessed lights typically have some of the biggest bills and comfort complaints.

Check out this photo I took of a group of recessed lights from the attic. 
I turned off the flash and my headlamp.

A recessed light as seen from inside of the house.

You can seal your recessed lights from the inside with an LED recessed light kit.
 

2. Seal Attic Floor Cracks, Holes and Gaps

Similar to the recessed light problem, there are other holes and cracks in the attic floor that will lead to the communication of air between the inside of the home and the attic, or outside.  Foam sealant can be purchased at the hardware store and it can be applied to the tops of walls, around light fixtures and to seal up holes drilled for electrical wires.  All of these voids contribute to a high bill and uncomfortable living space.

Wires run through the walls to hook up to electrical outlets and switches
creating pathways for air to connect between the inside and outside (attic).

A properly sealed top of the wall looking down at the attic floor.
 

3. Seal Accessible Leaky HVAC Ducts

Saving energy at home can be achieved when you put resources in the right place.  According to the EPA and other studies, the HVAC ducts in your home can be leaky enough to account for up to as much as 30% of a household's total energy loss. Sealing ducts is not something that needs to be done by a contractor.  This is a "weekend warrior" type of project that requires a little patience, a few materials and a little know how.  Sealing ducts near the air handler will also help you the most and those are usually the places that are most accessible.

Disconnected ducts are big energy wasters!

One way to fix leaky ducts is to use two-part spray foam.

Sealing ducts with mastic is another option to save energy at home
 

4. Seal and Insulate the Basement Rim and Band Joist

If you want to save energy at home and improve comfort, be sure to think about the unfinished areas of your basement, particularly at the top of the foundation walls.

Watch this to Learn How to Seal a Basement Rim Joist

5. Install a Chimney Balloon

If you have a fireplace, then you have another great way to save energy at home.  Most people keep the damper closed when the fireplace is not in use, but usually it is made of metal.  Chances are there is nothing stoping the flow of air through the chimney damper flap and out.  Using a very simple blow up type device can really help to move the needle and decrease energy usage and improve comfort.

A great way to save energy at home and improve comfort is to seal the chimney with an attic balloon.

The attic ballon has a stem that can easily be accessed to blow up the device and create a nice seal in the chimney.

 

Conclusion

High energy bills also typically mean uncomfortable homes.  The two go hand in hand.  So, if you follow these tips or decide to get an audit done and take advantage of incentives to get the work done, you are not only lessening your carbon footprint, but you will also be more cozy and comfortable as well.

________________

Written by Eric Gans
I have over 1000 energy audits under my belt in Maryland.  I like to take my personal experiences with each of my audit customers and try to get the things that concern them out into the world so others can make good home improvement decisions - in the right order - according to their needs.
 

Did these ideas help you save energy at home?  We want to know if you tried any of our solutions and how they worked out for you in the comments below!

 

 

Written by Eric Gans

I have completed over 1000 comprehensive home energy audits and hundreds of post-treatment test-outs. I have performed the tasks described in this article and I have also overseen technicians performing the work so that results, once the work is complete, are achieved.

 

 

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Table of Contents 1. Signs You Need Attic Air Sealing 2. Why is Attic Air Sealing Important? 3. Air Leakage Variables 4. How to Air Seal Your Attic  5. Air Sealing Electrical Hole - WATCH  6. Air Sealing a Bath Fan - WATCH 7. Measuring Attic Air Sealing Results 8. Air Sealing Health & Safety Considerations

 

If you want to know if you should air seal your attic, then you can ask yourself a few basic questions and quickly arrive at the answer. 

The easiest way to know is to determine if you have air sealing in your attic now.  If not, then you definitely need air sealing.

If you are not sure whether your attic is air sealed (who really wants to get in their attic?) then there are several things you can look for around the house that will tip you off. 

Tell Tale Signs You Need Air Sealing in Your Attic

The first tell tale sign is spider webs.  If you see spider webs dangling in recessed lights, near corners around mouldings in the ceiling or near the attic hatch, then you likely need to air seal your attic.

If you are feeling drafts around your home and different rooms seem more comfortable then others, particularly on extreme weather days, then you likely need air sealing in your attic and around other key areas of your home.

So, what is air sealing anyways?  Let's figure it out...

Reasons Air Sealing is Important

You don't have to be a home builder to know a little about how a house is made.  There certainly is no disputing that older homes, in particular, are not completely air tight.  We are able to breath when we are inside, after all.

So why is it important to seal up your house?  You need air to breath so what is the end game?

The biggest source of energy usage in a household bill is directly related to HVAC.  The less your HVAC runs, the lower your bill.  Pretty much that simple!

But, if your lucky, during extreme temperature days, your HVAC will actually catch up for a few minutes.

So, the idea when it comes to air sealing, is to prevent the air from flowing through those cracks in your building's shell, thus keeping it inside your envelope and keeping your home temperature more evenly controlled and comfortable.

Without effective air sealing in the attic, the R-value of your attic insulation actually suffers and that only adds to your woes. 

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Envelope Air Leakage Variables

A super interesting physics concept should not be missed when it comes to air leakage in a house.  Without some force, air will not simply flow through a crack or gap.  Loss of energy through any imperfect connection point is dependent upon the following factors:

• Weather Dynamic Pressure**
• Size of Crack
• Shape of Crack
• Location of Unwanted Connection Point
• Material where the Weakness is Occurring

**Pressure related to weather also illustrates why on a severely cold day, for example, that it becomes difficult to regulate temperature and keep a modest energy bill. 

There are two factors at play. 

1. The weather outside creates a greater pressure inside, particularly when the gap between the two temperatures is very high (25 degrees outside/ 70 degrees inside).  Greater pressure acts to push your conditioned air through the cracks faster.

2.  It is cold outside so the HVAC is running and the additional pressure created by the air flowing actually works to push the air through those cracks simultaneously while trying to heat or cool a room to the desired temperature, effectively creating a conveyor belt of conditioned air being delivered to places that nobody in the family is hanging out (outside).

Making matters worse, of course, is the fact that all the while that is happening, fresh cold air is being drawn in from other cracks in lower portions of your home.

Typical Leakage Point in Basement

In summer the pressure in an attic due to heat forces air through the cracks and as a basic and general rule, hot follows cold.  So, in winter the warm air gets pushed up into the attic and in summer the hot attic air gets transferred down to wreak havoc on your AC unit and bills.

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How to Air Seal

The general idea of sealing up a house is rather simple from 30,000 feet up. 

But, it can be kind of tricky when you are up in the attic and different ways the house is assembled creates unique air sealing opportunities.  Sometimes different situations call for different solutions.

Common air sealing materials include:

• Caulk or foam
• Sheathing tape
• Sheet metal
• 1/2" Polyiso (Rigid Foam Board)
• 3/4" Plywood
• 1/2" Drywall

A noteworthy takeaway from the list is that many common building components are listed as air barriers.  The key is sealing up the gaps!

Take a look at this new construction wall/framing assembly and the attention to detail that is given these days in some instances to sealing up a home.

Obviously, unless we are doing a complete remodel, this is not practical for finished areas in preexisting houses.  But, it does demonstrate the ways in which a home can leak and how to seal around any areas that are unfinished.

In a retrofit air sealing project, most of the "juicy" spots to seal are in the attic and basement. 

The video below shows a skilled technician air sealing the tops of walls (top plates), light fixtures and electrical wiring holes that were drilled when the house was built.  These are all places that air is traveling through, effectively escaping the inside if your "envelope" and costing you comfort and money.

The insulation is missing at the attic floor in the video and air sealing can be done when insulation exists as well.

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Air Sealing Top Plates and Electrical Penetrations

When watching air sealing taking place it starts to make a lot more sense.  Of course, there is no way to actually see the air flowing through these tiny gaps in real time, but what does happen over time when there is insulation in place is that the air flows through and around around the insulation leaving dust and dirt in is track.

In the photo above taken at the top of the hallway push up attic access hatch is a great illustration of a few things. 

First, you will notice the electrical wires that are running through the top of the wall above.  The wires feed the hallway switch seen down below. 

The insulation around where the electrical wires are fed is discolored telling the story that is all too common in homes that are not air sealed.  Air is moving through those holes on the regular and air carries dirt and dust.  Over time it adheres to the insulation which proves this important point. 

Add all those holes up around your home and you have a nice big gap that can easily be the equivalent of having an open window in your home all year long.  Having the attic unsealed is actually worse than having a window open because of the pressure being the most at the ceiling pushing through more air leakage as a result.

Besides electrical penetrations, there are many other areas in the attic that need attention for sealing.  More examples include:

• HVAC Chimney Penetrations
• HVAC Duct Penetrations
• The Attic Access Panel (pull-down stairs/ push-up hatch)
• Thermal Bypasses Due to Bulk Heads
• Knee Walls
• Recessed Lights
• Bathroom Fans
• Plumbing Vent Stacks
• Chimneys
• Electrical Box Bypasses
  
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Air Sealing Bathroom Exhaust Fans

Have you ever been in the bathroom on a cold day and wonder why it feels so cold in that area despite it being more comfortable in the adjacent room or hallway?  Sealing exhaust fans is an important nuance when it comes to attic insulation and they need special attention, particularly if you are experiencing temperature variance in rooms that they exist.

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How to Measure Air Sealing Results

While listening to a podcast recently, I was struck by something that one of the hosts of the show said.  Essentially, the saying goes something like this: 

A measured project is a managed project.

There is nothing more true than this statement when it comes to air sealing an attic.  One of the most difficult things to do is check on the work once the attic is insulated.  Moving insulation around once a project is "completed" is grounds for decreasing the overall effectiveness of the work that was done.  That is obviously counter-productive. 

If you are doing this project on your own then the dynamics change and what I am about to say is not nearly as critical.

But, if you need to hire a professional, you should make sure that the company is going to perform a blower door test or air leakage test - before the work is done and after.  This way, you can measure the results of sealing up the cracks.

The blower door measures the house's "leakiness".  So, getting a flow number after can be compared to the initial number and results can be taken away in the form of a before/after.  

The best way to have this done is to get a home energy audit if you have that available in your area.  In Maryland, the local utility companies work within the Home Performance with ENERGY STAR parameters and it is a great program for the residents of the state.

Watch this blower door test reveal the leakage in recessed lights.
 

The test works by pulling all of the air out of your house and as each little bit of air leaves it is immediately replaced by air from the outside of the "envelope", thus creating a flow at the fan that is measured in cubic feet per minute (CFM).

If the recessed lights in the above video are sealed properly, they will no longer leak and it will reduce the overall flow through the fan and record a reduction.

Here is an example of readings from the same home before the work and after with the accompanying signed test-out result form.

Air Flow at Test-In = 4949 Cubic Feet Per Minute After Air Sealing Air Flow at Test-Out = 3552 Cubic Feet Per Minute 28% Reduction

The actual result sign off sheet for the homeowner.

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Health & Safety Matters to Consider when Air Sealing

Two building science principles every homeowner should know

• Air Changes per Hour
• Indoor Air Quality

Air Changes Per Hour (ACH)

Air changes per hour (ACH) can be defined as the amount of times the volume of air inside your home changes with the outside air.  It is the house "breathing" in effect. If your house is calculated at 7 ACH then you can expect that on any given day and during any given hour, the inside air will exchange with outside air seven times. 

ACH in new construction homes has to be very low (3 or less).  New building codes for energy efficiency are making builders install energy efficient measures at the time of construction so that all of the typical leakage points are sealed before walls and ceilings go up which makes those areas very difficult to treat after they are in place (like in preexisting homes).

Controlled vs. Uncontrolled Fresh Air

But, when we tighten up the envelope and don't allow the house to "breathe" as much we have to find solutions to create the right amount of ACH for healthy indoor air quality.  The key to this is to make sure the introduction of fresh air into the building is controlled so that less energy is consumed to maintain good indoor air quality (the right amount of fresh air) rather than allowing it to infiltrate uncontrolled causing heating and cooling systems to work much, much harder.

Indoor Air Quality - What is it Actually?

So in considering indoor air quality, it is important to know that measuring indoor air quality is NOT to measure the amount of particles in the air.  Indoor air quality is actually making sure that a building has enough fresh air and in a manner that is cost-effective.  Good indoor air quality also goes a long way towards sustainability and the longevity of the buildings structural components.

Combustion Safety

A home environment is subject to many different dynamics including pressure.  Pressure inside a home varies from house to house, neighborhood to neighborhood.  When a combustion appliance, such as a hot water heater or furnace is running, the conditions in the house could change the way the appliance runs.  If the change is too much for the system, it could cause a hazardous situation inside the home to unsuspecting inhabitants.  

Combustion safety testing for gas fueled houses is a key to a safely air sealing a home.  Much like the blower door test where the air leakage is recorded before any changes and after, the appliances are tested prior to any work being done.  Once the work is completed, the testing is conducted again to see if the resulting "tightening of the envelope" creates any spillage or adverse conditions inside the home.

Get Your Scores Today! - Home Energy Audit

A comprehensive home energy audit is a great way to have your home evaluated.  Measures can be prescribed in a way that will address indoor air quality as well as energy efficiency and comfort.  It is the whole house approach that ensures that you can have the best indoor air quality and a less drafty house at the same time.

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________________

What do you think about air sealing your house?  We want to hear in the comment section below!

________________

Written by Eric Gans
I have over 1000 energy audits under my belt in Maryland.  I like to take my personal experiences with each of my audit customers and try to get the things that concern them out into the world so others can make good home improvement decisions - in the right order - according to their needs.
________________

It recommended that the attics in our homes are insulated to between R-49 to R-60. 

How much insulation you have determines how much insulation you need.

 

If you are having comfort issues in your home there is no doubt that a good place to start looking for answers is in the attic.  

Attic insulation projects can be better understood and considered with a little effort and knowledge.

To get things going you must identify two main things:

1  What insulation material exists up there now to figure out the R-Value per inch of what you already have (use the guide below)
2  Determine the insulation level in inches and general condition to calculate the R-value (download the spreadsheet)  

Once these two steps are complete, you can determine if you are meeting your regional insulation building codes.

Before Getting Started - A Few Basics
 

What is the R-Value?  The Answer in "Lay" Terms

R-value is the conventional method by which the performance of insulation is measured. 

Insulation has one job - to resist heat flow.  The higher the R-value, the better the insulation resists the transfer of heat.

Attic insulation can have a huge impact on your overall comfort, energy bill and HVAC performance.  A well-insulated attic can make an old heat pump or furnace seem like it is brand new if the project is managed and installed right!

Attic insulation is very important no matter where you live because in summer, it is responsible for stopping the hot attic air from coming inside (it gets 150 degrees in attic!!) and in the winter it keeps the warm conditioned air from going outside (through the ceiling mostly, due to pressure). 

The attic is the most important place to check first, however there are other areas that should also be considered such as the basement, overhangs and crawl spaces.
 

General Insulation R-Value Requirements

LOCATION....REQUIRED R-VALUE

Typical Places You will Find Insulation 

Attic Flat..........R49
Attic Slope..........R38
Vertical Wall (basement, crawl space, knee wall)..........R13
Crawl Space Ceiling..........R25
Below Cantilever..........R25
Rim Joist (top of foundation wall in basement)...........R19

Step 1 - Determine what Type of Insulation You Have

Different attic insulation materials yield different R-values based on how many inches are in place.  So, an important piece of information to determine your insulation R-value is to identify the type of insulation that was installed in your attic. 

Fiberglass batts, loose fill fiberglass, loose fill cellulose, mineral wool and two-part spray foam are all insulation materials that you might find in a typical attic.

Need help with this?

Pop your head up in the attic and take a photo of your insulation or if you live in an area that offers an energy audit program - take advantage and have a trained professional check for you.  

You can also call or email it to me so I can take a look and identify it for your eric@hometrustremodeling.com or refer to the photos below to try and figure it out.

Identifying the Most Common Insulation Types
 

Cellulose Loose Fill

General Characteristics

• Grey in color
• More dusty and clingy than other materials
• Has bits of newspaper in it
• Good fire/mold retarder w/ additives

Rolled Fiberglass Batt Insulation

General Characteristics

• Typically referred to as batt insulation
• Has the kraft paper or aluminum foil on one side
• Recognizable due to the "Pink Panther" commercials
• Must be installed flawlessly (unforgiving)
• Low R-value per inch if not installed properly

 

Fiberglass Loose Fill

General Characteristics

• Typically white shreds, pink squares or yellow shreds.
• Much less dusty
• Lower cold weather performance than cellulose

Different Insulation Types = Different R-Values

Once you determine your insulation type it is time to figure out the material's R-Value. 

R-Value is sometimes misleading because several factors will have an impact on R-Value, including:

• Installation integrity
• No pressure boundary (air sealing)
• Overall insulation coverage (evenly distributed)   

R-Values can be multiplied by the number of inches to see where your attic falls on the scale.

It is important to note that the R-Value listed here is based on materials that are in use at the attic floor, not "brand new".

• Loose Fill Cellulose
  3.13 R-Value Per inch
  (Example: 6" = R19; 10" = R31)
• Fiberglass Batt Insulation
  2.10 R-Value Per Inch
  (Example: 6" = R13; 10" = R21)
• Loose Fill Fiberglass
  2.73 R-Value Per inch
  (Example: 6" = R16; 10" = R27) 

 

Step Two: Calculate a Reasonable R-Value Based on Your Attic's Overall Condition

Insulation levels in a typical attic are rarely the same everywhere.  In order to gain an true perspective on how much insulation an attic needs will depend on what condition the existing insulation is in and what the levels are throughout the attic floor. 

Un-insulated Areas Play a Heavy Hand in Poor R-Values

Now lets go a little deeper and explore the impact an un-insulated surface has on the entire area when it comes to overall R-value.  If you go in your attic and see any area that does not have insulation, you should really pay attention to the information below.

To demonstrate the impact having no insulation has on the overall R-value, I am going to use a common set of circumstances in a typical flat attic.

For this example, the attic area in the home pictured above is 975 square feet and flat (R-49 recommended for this particular region). 

At the attic floor you see 1" of loose fill fiberglass insulation (white stuff in photo below) and 7" of rolled fiberglass batting laid on top. 

R-Value for the insulation in this attic = R17 (using this guide)

Here is the catch...

There are two major un-insulated areas in this attic (very common in our area). 

1. A three foot by three foot push up hatch
2. A three foot by three foot whole house fan

Equaling a total of 18 square fee of un-insulated area at the attic floor. 

This equates to just about 2% of the overall attic area (18 divided by 975).

   
Typical hallway push up hatch leading to an under insulated
attic.

The hatch from the attic has a plywood cover (seen in background)

Whole house fan as seen from the attic.

When calculated using the Home Energy Score Averaging Calculator it is clear that un-insulated surfaces can have a negative impact on the overall performance of your insulation. 

A 975 square foot attic with 18 square feet of missing insulation reduces the R-Value from 17 down to 13 - for the entire attic!

Calculating the actual area with insulation in combination with the areas that are not insulated yields a significant reduction in overall R-value as seen in the two scenarios above.

Conclusion: if as little as 2% of your attic surfaces are un-insulated it can have as much as a 25% negative impact on the overall R-Value of your current insulation.

What does this mean in the easiest to understand terms?

If you are missing insulation in as little as one or two areas of your attic, your overall comfort and energy bill will suffer!

GET THE INSULATION R-VALUE CALCULATOR FILE HERE
 

Watch a blown cellulose attic insulation job in progress!

What Next Steps Can You Take if You Think You Don't Have Enough Insulation?
 

And if you are not interested in poking around in your attic, then you should sign up for a home energy audit if it is available in your area.

Thank you for reading.

There are literally thousands of homeowners in Maryland that are a lot closer to having a more comfortable home than they ever could have imagined.

Let me explain...

This past March I did a BGE energy audit in Howard County for a really nice family that just moved back to Maryland from a warmer part of the country around the end of summer 2020.

They reported to me that their first winter here was brutal. 

Cold spots at every turn, drafts in areas they enjoyed to spend time and the basement has been all but abandoned, despite having a nice playroom and a video game console with surround sound.  But on the coldest days it was just too much.

Two Reasons this Audit Makes a Great Case Study

First, the family was pretty much in the dark all winter about what they could do about their issues.  They love the home and the location, but something seemed wrong and they really did not know where to turn for solutions.  The HVAC was running continuously and never caught up.

Here is the other thing too - they just came off of having a home inspection done when they bought the property. 

What I have observed from time to time is that a home inspection gives homebuyers a false sense of security, particuarly when it comes to insulation. 

The inspection is more in line with the old way of thinking about insulation...

I see pink stuff in the attic - all is good. 

The box gets checked and you, the end user, is puzzled by the drafts and looking at windows and doors for answers to why it is so cold.

But, as you will see, the inspector missed a few key things and did not give any guidance at the time that would assist the family in finding a swift solution.  So, instead, they spent the winter draped in blankets studying their window and door seals wondering if there was anything that could be done.

We cannot blame the inspector though.  Some of the key insulation concepts get lost on the best home inspectors.  It can get a little complicated.

The second thing that was fantastic about this scenario is that the BGE Home Performance with ENERGY STAR® program helped the family uncover their underlying issues and incentives, available to all BGE and Pepco customers, also paid for 70% of the cost in this case.
 

"The BGE Home Performance with Energy Star® Program will pay for 70% of the cost."

Sorry, that was worth repeating!

The part about all of this that gets my wheels spinning is how many other people are out there, enduring miserable winters, or hot summers for that matter, that could also benefit from this program in the exact same way.

This case study clearly demonstrates why an energy audit is such a critical assessment for a home to undergo. 

The same problems are happening in households everywhere in Maryland. 
  

Energy Audit - A Critical Home Assessment

An energy audit can illuminate comfort problems that would otherwise stay hidden in plain sight and this case study is a classic.

The Symptoms for this BGE Customer Case Study

-HVAC running all of the time
-Never really feel warm on the cold days
-Shockingly high energy bills
-Cold basement
-Drafty top floor
-Cold master bathroom
-Cold kids bedroom

I want to stop here and place a little emphasis on this list. 

I believe that this is where the disconnect exists for a customer that has these issues in their home and never gets an energy audit done.  

There is an expression that my dad would use - "if I had a nickel for every..."

If you add up all of my energy audits over the years, I would say that I would have fully completed roughly 1300 of them.  And, if I had a nickel for every customer that blamed their windows and doors - I would likely have 40 bucks (that is about 62% of the people if you don't wanna do the math).

The underlying message here is that if you have not gotten an energy audit because you think it is your windows and doors, then you might be surprised. 

Most people that have the audit done always seem quite enlightened by what is actually causing their problems.

 

The Case Study - Figuring Out the Root Cause

An energy audit is a process of gathering data points around your home.  The volume, square footage, foundation layout and type are all important to help you find the best solutions for making things better.

Sometimes, the first hour of an audit does not prove to be fruitful in terms of "opportunities" for improvements, or retrofits.  A well trained energy auditor never wants the cost of the project to outweigh the benefits.  An auditor is on the hunt for the low hanging fruit.

As an energy auditor, you can have some fun with this. 

It can be much like the game show Let's Make a Deal.  Every door you open to an attic or crawl space presents a unique set of circumstances that will either prove to be a great chance to move the comfort needle for the customer or it could be a dead end.

Now, this can also be kind of a slippery slope.  Great opportunities also come with a cost.  Meaning, if your home is stubbornly uncomfortable and the places that require insulation are under insulated and accessible that is fantastic because you can fix it!  But, it also means that you have to spend money to do so.

But, as mentioned, there are incredible incentives through BGE and Pepco available to help manage the cost.
 

Time to Investigate the Attic

This particular home has two sections of accessible attic space. One access point is in the hallway.

I took a trip up through door number one to inspect the attic space.

The first sign upon poking my head up is that the attic floor is insufficiently insulated.  One thing I have learned through the years is that those with some of the biggest issues have rolled batt insulation in the attic as this home did. 

Read what John Krigger and Chris Dorsi say about fiberglass batt insulation in the book Residential Energy: Cost Saving and Comfort for Existing Buildings

"All of the common facings attached to fiberglass batts are air barriers and most are vapor barriers.  However, their effectiveness as an air barrier depends on nearly flawless installation."

Fiberglass batt insulation is almost always not installed to perfection.

Now, I can't be sure about what I am about to say, but this is where I believe most energy auditors stop.  They take a quick peak at the attic and draw every conclusion for that specific attic area without proper investigation.

I take pride in going the extra few steps and I find that is usually proves to be beneficial - for my customers.  The rule is if I don't really want to go over to that spot then chances are not too many people do and therefore there could be a problem there that nobody has ever seen.

When I got in the attic and made a 180 degree turn, I saw what appeared to be a knee wall that was missing insulation.  The area was in a tough to reach part of the attic.

I decided to go around the corner to see what was going on because it was not quite making sense to me.  As with anything that you do on the regular, patterns emerge and a more comprehensive understanding of what you are doing comes over time - aka: experience. 

Adding to my sense of curiosity was the fact that during my initial tour of the home, the customer had pointed out to me that some remodeling was done in the vicinity below before they bought the home. 

A good home energy auditor has to be a like a sponge, absorbing bits of information throughout the time at the home so it can all be pulled together to produce sound solutions.

 

Then, once I was able to poke around the corner this is what I found.  A ten by ten area of un-insulated attic space hiding behind that wall. 

This is important for two reasons. 

Reason One - it speaks to the issues that they were experiencing on cold days.  Having insulation at the attic floor is the most important place to build the insulation boundary because the pressure is greatest.  

Hot air rises in a building and it wants to fly right out of the top and will if you let it.  Cracks and crevices are certainly big time issues for this, but because insulation slows the transfer of heat, the thin drywall alone is no match for the heat to escape at very high rates. 

Missing insulation is a big time issue. In an earlier article I wrote about how I examined the impact of an un-insulated three by six foot area in an approximate thousand square foot attic (2% if the area) equated to a 25% reduction in the overall R-value of the insulation in that particular attic.

Reason Two - it produces a larger incentive through the BGE Home Performance program.  Some of the rebate calculations are based on how much insulation an attic currently needs and when there is nothing, it pushes the incentive up. 

Missing the un-insulated area and modeling the home as if it did have insulation in that area would be cheating the customer.

My final mission while in this section of the attic was to determine if I could make passage to the other side of the home and I was able to confirm that I could not and had to use the second attic entrance.

Second entrance to the attic was located in the master bedroom closet.

More of the same in the second attic area.

The verdict is in!  This attic needs to be air sealed and insulated.  Time to run the numbers!
 

How Does this Program Pay for 70% of the Cost?

In order to help you understand how this program works, I will share the exact numbers from this project and how it worked out so favorably for this customer and you can hopefully gleen information to compare to your own situation and see if you can benefit like the family in this scenario.

But, if you don't have all or any of these characteristics in your home, that does not mean you will not qualify for rebates or that an energy audit won't uncover some totally different issue for you that will find a way to make it well worth your while.

The Numbers

Prioritized List of Energy Efficient Improvements

Total Cost of Improvements: $9500.00
BGE Incentive for this Project: $6640.70

Total Ratio: 70% of the total cost
 

Financial Analysis

A financial analysis will indicate annual realizations and provide simple payback years. 

How many home improvement projects actually pay you back?
 

Summary of Proposed Improvements

Whole House Air Sealing

When receiving rebates through the BGE Home Performance Program with ENERGY STAR, the blower door test is an integral part of the overall incentive structure and it is tied in many ways to each individual item listed on the list of improvements.

For example, when treating the attic on this project, by far the largest component of the improvement plan, sealing must be done at the attic floor so that the insulation performs to the R-Value it is designed to meet. 

Basic Air Sealing

This is also a key to the whole house air sealing plan.  At the end the house is tested again for air leakage.  The overall leakage is reduced by the acceptable figure established by the program (10% minimum to qualify).
 

Rim Joist - Accessible

The top of the foundation wall in any home is leaky and needs to be sealed.  The question is how much of the area is unfinished and accessible to keep the cost vs. value in line.
 

Knee walls/Vertical Attic Walls/ Slope Transition Locations

 

Not all homes have knee walls so this section may or may not apply.  Knee walls are very difficult to visualize.  Photos can help.

Top photo: thermal image of the knee wall that is created by the transition from a sloped ceiling back to a flat 8' ceiling.

This image is taken at the exact same time the top thermal image was taken for point of reference.

This is a look at the missing insulation at the knee wall from the attic.

Attic Insulation - Sloped and Flat Areas

Once all of the "little" things around the attic and basement have been sealed and insulated and the attic floor areas have all been sealed, it is time to lay down the blanket..so to speak.

Blown Cellulose Demo

Improvement Results

Getting a considerable rebate on a project around the home that you still have to come out of pocket some money for won't be worth it if the results are not there.

The great thing about the BGE Home Performance with ENERGY STAR program is that we measure the results at the end.  This is done in a few diferrent ways.

Visual Inspection

Once the work is done it is the responbility of the energy auditor assigned to perform the final test to check the work that was done.  If they were not on the job, this can be done by simply looking in the attic.  The blower door test will reveal if air sealing was not completed, but it is very difficult to look for air sealing once the insulation has been installed.

Blower Door Test

The Blower Door Test

When the blower door test is done at the audit the "test-in" measurement is recorded.  A portion of the incentive and the customer's long term savings and comfort is also tied to the blower door test and that is why it is so important to the overall job process and the BGE program.

Here are photos of the actual blower door test results for this case study.  The numbers look really good!

Air Flow at Test-In = 4949 Cubic Feet Per Minute After Air Sealing Air Flow at Test-Out = 3552 Cubic Feet Per Minute 28% Reduction

 

Customer Satisfaction - Measured Results

It is one thing to hit the mark on the numbers and achieve the goals when it comes to measuring the work that was performed.

Another part of a successful Home Performance with ENERGY STAR project is the customer's overall experience.  It certainly would be fantastic to have a more comfortable home with lower bills, but having a pleasant experience along the way should also play into things.

Based on a recent review by the customer on Google, it seems like we hit the mark on this one too!  Making this a successul project all the way around!

"Had a great experience with Eric and his team. Eric conducted our home energy audit taking time to point out and discuss the good and bad, answering all my questions. He also took care of the whole rebate process with the local utility. All phases of project completed in about 3 weeks. Easy and painless. Definitely recommend Eric and the Hometrust team!"

Read the Review Here
 

Need Advice on How to Do Something Like This?

If you are interested in making your home more comfortable and more efficient, give me a call.  We can discuss your situation and likely getting a BGE or Pepco Energy Audit is the way to go.  

Incentives through the program can be quite advantageous, particularly for those that know that they have to get this problem resolved once and for all. 

Furthermore, an energy audit can uncover other factors that can contribute to your specific issue as each home is different - even the same model across the street.

Give me a call!  I'd love to help you out!

Written by Eric Gans
I have over 1000 energy audits under my belt in Maryland.  I like to take my personal experiences with each of my audit customers and try to get the things that concern them out into the world so others can make good home improvement decisions - in the right order - according to their needs.