Charlie Gohman & Ken PancostArizona Department of Commerce

Energy Office

Energy Efficient Housing

Homes That Work

Importance of Energy Use

• Energy use in your operations is going to grow in importance for one simple reason.

Energy is going to get even more expensive!

How Much Will This Family Impact the Cost of Energy in the Furture?

What Can You Do?

• Supply your own power.• Reduce the demand for energy.

– Today we will be talking about how you can maximize the savings you can get with your limited resources.

Report on DSM programCost to save a kWh

Less then $.01

Here Is How You Do It!

• Demand the right thing done right.• Get the right thing done right.• Verify that the right thing was done right.

– Do not expect performance if you do not inspect for performance.

How do you determine what the right thing is?

Energy Efficiency Yesterday & Today

What if you don’t feel right and go see a doctor.

You walk in his office and the first thing he says is…

Take these pills and call me in the morning

What is wrong with that approach

• No diagnostic to determine what is making you sick so...– Some pills may help– Some pills may do nothing– Some pills may make you worse– Some pills may combine to kill you

This is how we use to do deal with homes!(some still are)

Old Approach• Measures are recommended/installed on

homes with no real understanding of impact on energy or other areas.– Lists of measures applied to all homes!

• Limited testing to determine problems in individual homes.

• Limited commissioning/inspection to make sure measures really work.

My First Bit of Advice

• If someone come in and says ”I can solve all your energy problems” without a detailed audit/inspection plan, show them the door.

• They may end up doing the wrong thing right.– I will review some of the aspects of what a

detailed audit should include.

Today’s Approach

• Gather complete data on existing characteristics of the home.– Need information on all the characteristic that

may impact your decision making process.• Based on data about the house, develop a

scope of work.• Inspection of work to insure it is competed

per scope.

General SpecificationIf you take one thing away today, this

should be it!

• New construction – EPA Energy Star (+ room pressures)

• Existing - EPA’s Home Performance with Energy Star Program – An auditor/contractor should be certified by the

Building Performance Institute.

Work is inspected

Home Performance with ENERGY STAR

A whole-house program with contractor participation and quality

assurance.

AZ HPwES(602) 532-2976 ext. 1

Building Performance InstituteBPI

• The Building Performance Institute, Inc. (BPI) is a recognized global leader, supporting the development of a highly professional building performance industry through individual and organizational credentialing and a rigorous quality assurance program.

• Foundation for Senior Living Home Improvement is the local affiliate of BPI and trains and certifies local technicians at the Southwest Building Science Training Center.

Southwest Building Science Training Center

• Operated by Foundation for Senior Living Home Improvement.

• Funded through the Department of Commerce Energy Office and Local Utilities.

• Goal to provide building trades with the knowledge and skills needed to successfully perform diagnostic and repairs on Arizona’s housing stock.

If there is any interest in having your staff trained, let me know!

The Right Thing

• Details on the key “right things” that must be looked at in each building.

Why Do We Build Homes?

• Our housing stock should be:– Healthy – Safe– Durable– Comfortable– And Energy Efficient

Making a home more energy efficientbut less safe is the right thing done wrong!

Energy is #5• Energy was number five on the list.• Never do anything to save energy that will

negatively impact health, safety, durability or comfort.

• As you take energy out of a house (energy efficient) it becomes much less tolerant to:– Heath and safety issues– Durability issues– Comfort issues

The Good News• You can achieve all five if you use applied

building science when building or retrofitting a house.

• Understand how to take energy out without the increasing the potential for problems.

Again, if someone does not talk about all of these issues, only talks about all the energy you will save, they do not know

what they are doing!

Things are changing• The introduction of Building Science is changing the

way homes are built & retrofitted.

$.25 per sq. ft. per year

Phoenix Home Energy Efficiency Study

• Baseline Homes– R-30 attic– R-19 wall– 56% low-e– 12 SEER

• Performance Guarantee– R-30 attic– R-19 wall– 100% low-e– 11.9 SEER

Study sponsored by the EPA, performed by Advanced Energy Corporation

The Performance Guarantee homes out performed the Baseline by 33%.

How is it done?

Getting The Basics Right

All the right pieces, put together wrong.Is this safe?

A House is a System

• A house is made up individual parts. • We keep adding more and more parts.• For it to operate properly, all of the parts

must work together.– This means you need to understand how any

new parts may impact a building!– This requires testing!

• If not, lawyers may get involved.

Is a dryer a good addition?

• Yes, BUT– Dryers exhausts about 200CFM to the outside.– In one hour that is 12,000 cubic feet (total

volume of a 1500 sq. ft. home).– This air must be replaced by outside air.

• One CFM out = One CFM in– Where does the air come from?

• The attic, the garage or maybe down a chimney or vent?

– What is in the air? • Moisture, heat, cold, car exhaust, combustion by-

products….

The dryer hasbeen pulling the flame out of the heater.

Carbon monoxide(CO)

• CO is colorless and odorless.• It can be produced by a furnace, water

heater, fireplace, oven, car, anything that burns fuel.

• At elevated levels, carbon monoxide causes headaches, fatigue, queasiness, and at very high levels, brain and heart damage and death.

YES - DEATH

CO Testing is Standard Practice in This Field

• As standard practice, someone who does not test is open to higher risk.

• Testing is simple!

If you have combustion appliances, they should be

tested

Basic of Heating/Cooling Driven by Three Mechanisms

• Convection – Air flow into, out of and within the building (high to low pressure).

• Conduction – Heat, moving through materials (hot to cold)

• Radiation – Hot surfaces radiate heat to cooler surfaces.

This is it, it is this simple!

Must gain control of these flows

• Appling building science to address the key issues that impact all buildings.– Convection (Air flow) – Conduction (Heat flow)– Radiation– HVAC (adding or removing heat from

convection, conduction & radiation)

Infrared Camera

White is hotter 93.6°

Dark is cooler 86.6°

The shirt is insulating his body.

Uninsulated attic hatch is hot (white)

A Primer on Air Flow(Convection)

• Air flow is the most important flow!• For air to flow you need a hole and a pressure.

– No hole, no flow– No pressure, no flow

We have spent billions of dollars sealing holes with mixed results, when was the last time

someone talked to you about controlling pressures?

What Will Create Pressures

• Natural Forces (can’t control)– Wind– Stack (hot air rises, cold air falls)

• Fans (can control)– Exhaust (range, dryers, bath)– Air handlers

Wind Resources

It is not verywindy in Arizona

Stack• What does an AZ home look like to cool air? • Block or stucco walls, slab. How about your

house?

Cool Air Will Pool

Wind and Stack

• Natural pressures, wind and stack, just are not that strong in Arizona’s low desert.

• They do not cause very much pressure and will not force much air flow into or out of buildings.

• High country, wind and stack are more of an issue.

Pressures in Buildings• New studies are finding that on average

pressure created by fans cause 3 to 10 timesthe amount of air leakage then wind and stack.

Fans

• Exhaust Fans– Dryers - 200+ CFM– Range hoods and other kitchen exhaust are

getting bigger and bigger – 100 to 1000 CFM– Bathroom fan

• Air handler - 1000’s of CFM.

Fans

One out (negativepressure)

Equals one in

Where is it coming in and what is in it?

Attached or tuck under garage

A negative pressure created by a fan can:

Impact of Pressure Created by Fans on Your Health

Cause back drafting

Flame roll out

Carbon Monoxideand other fumes from a attached garage

Any fan

Fans

Where is the make up air coming from?

Do you have them in your housing?(Dryers, range hoods, bath fans)

All homes should be tested for potential back drafting, flame rollout

and issues with attached garages

Duct Leakage• National studies find an average of 300

CFM of duct leakage (1 ton = 400 CFM). On a 2000 sq. ft. home, that’s 15% of rated air flow. (AZ 371 CFM)

• Studies (80’s) from Florida estimate that 10% of Florida’s electrical generation capacity was duct leakage.

I would say this is the #1 issue in homesand can easily increase heating and cooling by

100%, 200%....

We take duct sealing very seriously

These holes are under a lot of pressure

How Not To Design Ducts

This is more common than you may think.

High Tech Duct Test

Do your ducts look like this?

If you think this is bad, wait!

That is the roof deck!

SO?

Roof Deck at 140ºWhat impact does 140º air have on AC SEER

140°

15% return leak pulling in 115º airreduces capacity by 50% (ac runs twice as long)

So what happens at 50% leak at 140º

Supply Leak

1,000 CFMreturn flow

200 CFM supply leak

800 CFM supply flow

What will happen with the house pressure?

As you loss air out of the leak, you are pulling air in through all of the holes in the house.

_

100º outside

140ºAttic

Suck

Return Leaks

800 CFMreturn flow

200 CFM return leak

1000 CFM supply flow

What will happen with the house pressure?As you pull air in the leak, you are forcing air

out through all of the holes in the house.

+

100º outside

140ºAttic

Blow

Common example are platform returns, a woodenbox with the air handler sitting on it. In most cases it is located in the hallway.

If you can see studs, you may have large amounts of duct leakage.

The air handler will suckair down these walls fromthe attic.

DO NOT USE A PART OF THE BUILDING

TO MOVE AIR!

This will not leak!

Ducts must be sealed withmastic, not duct tape

At least the air you are blowing through the tape and into the attic is filtered

Mastic

Mastic

Get the hintWe like mastic!

Boot to sheetrock, easy to get at

Boot to sheetrock, easy to seal

Leaks are expensive

Mastic is cheap

The patented ArizonaHigh Tech MasticApplicator

Five year, five thousand duct system warrantee

Ducts should be sealed with a water based mastic –Not Duct Tape!!!

Of any kind!!!!!

Duct leakage in the Arizona• APS study in early 90’s found 17% duct

leakage.• Today, new systems are consistently under

5%.• Systems should be tested!

StandardNew construction – 3 to 6 CFM/100 sq. ft.Existing – If you can reach a hole, seal it,

If you can’t, depends (need a trained technician)

Existing Ducts

• Weatherization program: We routinely get ducts close to if not beyond the new construction standard.

• Multi family example: We got the ducts so tight we could not get an accurate reading with a duct blaster (no leaks, no flow).

Goal for ducts should be leak free!

Duct Blaster testPressurizes ducts to

25 PascalsMeasures CFM leakage

Duct Blaster testNew construction, good at verifyingthat ducts meet standard Existing – Blower door or duct blaster

Doors and Energy Use

• What doors in your home account for the most heating and cooling costs?– Front and back doors– Patio doors– Doggie doors– Interior doors

In some homes this can be as big of an issue as

duct leakage

Doors Open

1000 CFMreturn flow

1000 CFM supply flow

100º outside

140ºAttic

1000 CFM flow through the house and is under neutral pressure

Doors Closure

1000 CFMreturn flow

1000 CFM supply flow

140ºAttic

Close a door and blockthe flow back to the return.

Return side will go negative.

Supply side will go positive

Now the home sucks and blows at the same time

DOOR CLOSURERated PG-13

Impact of Room Pressure(Door Closure)

Fixture (light out) 81.4 °.

Ceiling 75.8 °.Fixture (light out) 82.3°.

Fixture (light out) 87.9°

Ceiling 77.7 °.Fixture (light out) 85.5°.

What about the sheetrock temperature?

Fixture (light out) 87.9°

Ceiling 77.7°

Fixture (light out) 85.5°

Doors open Doors closed 20 minutes

Increased infiltration, hot air coming in the can lights.

The following video is a time lapse infrared of a homeunder negative 3 Pa pressure for 40 minutes.

Note starting temperatures.

80.8°

80.0°

82.7°

80.7°

88.9°

87.3°

90.9°

92.5°

Temperatures after 40 minutes.8 to 12 degree increase in surface temperatures.

Cheap Pressure ReliefProblems with light and sound

Don’t install vents in the door

Less issues with light and sound

Bedroom

Hall

link

Room pressure standardNo pressures greater then + -3 Pascal created by

the air handler (duct leakage or door closure)

Both APS and TEP includethis standard in their new home programs. EPA Energy Star Plus Room Pressures. Also part of AZ Tax Credit.

Closing doors can do this!!!!!

What About Holes

• Most of the holes in Arizona’s building are between the conditioned space and the attic.– Slab floors– Stucco/block walls– Doors and windows do not leak much.

• Each year you are told to seal them, weatherstripthem…

#1 rule on holes, seal the big ones

.

How big is this hole?All of the “interior wall” cavities that it is connected

to are really outside and uninsulated.How big is this hole?

This big!

Looks good, right

A Flag!

Opps, That is one big hole.

Pretty basic!

Can lights, 1 sq. in. hole per light

The air moving from the attic into the house is at least filtered

right wrong

Sealing hole is a good idea butcan we build a home too tight?

•Build as tight as possible•Pressure balance the home (less than +/-3 Pa)•Carbon Monoxide detector in homes with

combustion appliances or attached garage.•Ventilated right

–Continuous fresh air ventilation of (bedroom + 1) X7.5 CFM + 0.01 CFM per sq. ft.of conditioned space.–Spot ventilation in kitchen and baths

NO Here is the standard(new construction)

Do You Need Ventilation in a Existing Home?

• Ventilation requirements depend on:– How much do you have (fans and leakage)?– What is in your home that needs to be vented

(pollution sources)?• Number one pollutant (causes the most problems) in

an average home is…

Moisture

It not how tight a house is but if additional ventilation is needed. But no one would seal up (decrease ventilaiton) a house without

testing, right?

If this is not being using (by trained tech), you are not doing it right!

Blower Doormeasures how leaky a house is.

Control of the Air

• Continuous (really tight) air barrier that keeps the inside air in and the outside air out.– Sealed ducts– Pressure balanced – Sealed envelope– Ventilated right

Heat Flow (Insulation Performance)

• The approach to insulation has always been that more is better. At some point, this is wrong!

• The key to controlling conduction is not how much insulation (R-value) is installed, but how well the envelope slows heat flow.

Insulation

Why not just require R-60?

Heat Flow/R-ValueSq. Ft x Delta T x U-value = Heat Flow

• 1000 x 20 x 0.5 (none) = 10,000 Btus per hour• 1000 x 20 x 0.1 (R-10) = 2,000 Btus per hour • 1000 x 20 x 0.05 (R-20) = 1,000 Btus per hour• 1000 x 20 x 0.033 (R-30) = 660 Btus per hour• 1000 x 20 x 0.025 (R-40) = 500 Btus per hour

Will you ever be able to save8,000 Btus again?

R-value vs. P-valueDesigned heat flow vs. real heat flow

100% R30• .033 (R30) x 1000 x 20 = 660

BTUs

95% R30 - 5% uninsulated•.033 (R30) x 950 x 20 = 627 BTUs•.5 (none) x 50 x 20 = 500 BTUs•Total BTUs (same as a R16) 1127 BTUs •Small defects can have a large impact, today’s complex

home design is tough on the insulators.

R-Value

% defect0 5% 10% 20% 30%

R-30

R-20

R-10

R-16

R-12.5R-7.9

R-5.7

Impact of defects on effectiveR-values.R-30

#1 concern, quality or quantity?

Is there enough insulation? (insulated to code-R-30)

Does it work?

Attic With No Insulation

Stud (R-4)

R-0

Stud R-4

R-30 Batt

Why do the last two pictures look the same?

Insulated Attic - R-30 Batt

Why is the wood (R-4)cooler than the R-30batt?

Wood is letting lessheat in thanthe batt.

If it’s insulated, why isn’t it insulating?

• Defects are allowing hot or cold air to pass through or around the insulation.– Air is a fluid (just like water). If water would

pour through a material, air can also pass through it.

• This will drastically impact the effectiveness of the insulation.

Insulation Problems• Voids (area with no insulation)• Gaps (part of an area not insulated)• Wind intrusion• Compression (not installed at full thickness)• Misalignment (must touch the air barrier)

Insulation stops air flow based on its porosity.

Yes, this is a void.

Void

Stud (R-4)Dry wall only (R-0.5)

Gap

Gap

Will be there for the life of the building!

Wind intrusion, what’s that?

Perimeter radiant heating?No, wind intrusion.

High tech solution, cardboard

Compression

Compression

So if the stud is an R-4, what R-value is the insulation?

R-4 stud

R-???

What is happening? Misalignment

Misalignment

• The house must have a continuous air barrier. (Stops air flow)

• The house must have a continuous thermal barrier. (Stops heat flow)

• The air barrier and thermal barrier must be in 100% contact.

• If not, hot/cold air will pass through or around the insulation.

We have missed this one!

Misalignment

Air barrier

Insulation

Insulation is placed here

But the heat is getting here

Knee-wall insulation attached to the back of the stud.

The Sheetrock, cooled by the conditioned space will cool the air between the Sheetrock and insulation.This cool air will fall and be replaced byhot attic air. In heating season, just reverse the arrows.

Knee-wall insulation attached to the back of the stud.

The Key to Insulation PerformanceStop Air Flow

The insulation is suspended over the soffit and does not touch the

Sheetrock.

No air barrier

Allows air to flow through the insulation

Now these surfaces are uninsulated exterior surfaces(but the air is filtered)

Air barrier installed by the framerNow the insulation is in contact

with an air barrier.

Air barrier

Stops air flow through the insulationand brings that space “inside”.

Installation of air barrier

Thermo-Ply air barrier

Continuous air barrier made up of Thermo-Ply and Sheetrock

Now this space is inside the conditioned space

No air barrierAir barrier and insulation aligned

Home with no air barrier Home with air barrier

Same corner

Home with no air barrier Home with air barrier

A piece of insulation that is working!

Test, what is this?

Insulation that works•No gaps•No voids

•No compression•No misalignment•No wind intrusion

Incorporate into specificationsImportant even in retrofit

New Insulation Standards

• EPA Thermal Bypass Check List• These insulation standards are new.• If you housing stock has not been built

under a program that requires these standards (Energy Star, EFL, TEP Guarantee, AZ Tax Credit) there is a good chance you have problems.

• Can’t just look at R-value!

Radiation

Guess what, we get a little bit of sun here

Technical Break ThroughDirect From Researchers in Arizona

Shade

Urban ShadeNeighbors Helping Neighbors

Partial Shaded WallShaded - 108Sun - 148

Heat flow (delta T)on sun struck wall

is more than double shaded wall.

Shade reduces the Delta T

reduces heat flow.

Reflective products

• EPA Cool Roofs – Reflective roofing products. Effectiveness based on product’s solar reflectance.

Any reflective product (paint) that claims an R-value is…

Roof deck - 150ºAttic air - 120ºInsulation - 140º

Remember HS physics,Second law of thermo-dynamics says heat moves from high to low temperature.

How is heat flowingin an my attic at noon?

IR of my attic, summer at noon (105º)

Before reflective roofcoating - 93 degree ceiling temperature

After reflective roofcoating – 87 degree ceiling temperature

Do not coat asphalt singles

Radiant Barriersdeduce summer attic heat gain

16% to 42%

Reflexive Coating/Radiant Barrier

• Saving for these products are directly related to the effective R-value of component used on.– Higher the R-value (that is working), less of an

impact on your bills.

Attic FansHeat flow in an attic is driven by the roof deck temperature.Fan will not impact the roof deck (minimal impact on insulation temperature)!Fans will pull air out of the house!Fans consume power!

Windows

• New construction – Low -E• Existing windows - It is very tough to justify

(energy savings) replacing existing single pane windows with new windows.

• Best approach, shade the windows (low desert).

• If you are replacing windows, go with Low-E. (EPA Energy Star)

HVACThe 12/7 Rule

• Buy a 12 SEER you may only get a 7 SEER– Duct leakage (talked about this one) – Improper air flow– Over or under charge of a system– Improper sizing (bigger is not better)

www.advancedenergy.orgSEER Fact Bulletin

Air flow

• Low air flow is often caused by:• Ducts that are too small (big problem for

returns).• Duct layout that restricts airflow.• Poorly selected or restricted grilles.• Mismatch of air handler with the other

equipment.

Charge

• How common are improperly charged systems?• About 7 out of 10 systems have an improper charge.

While most systems are undercharged, some systems are overcharged by more than 100%.

• Systems with longer line sets tend to be much moreseverely undercharged than systems with shorter line sets.

• Mismeasurement of line set length is a commoncause in precharged systems.

Sizing• Over sizing has a negative effect on energy use,

comfort, equipment life, and system costs:– Oversized system run for short period and do not reach

steady state efficiency (think of city vs. highway driving). Impacts both cost and life.

– Short run times means the air does not get mixed, causing hot spots.

– Short run time will not remove humidity, increasing comfort problems.

– Over sized equipment cost more to install.

Use Manual J

Steady State Efficiency• Mechanical devises take time to go from

start up to their peak, steady state efficiency. Some, like AC units will take minutes. (SEER incorporates this start up time)

SEER

Time

Start-up

Steady State

Over sized system replaces steady state with start-up, loweringefficiency.

Real Example• House built right, HVAC contractor want to

install 12 tons total. (peak demand around 10 kW)

• Installed 5 tons, monitors at 110°, used about 90% of capacity (peak demand about 4.5 kW)

This has a huge impact on the numberof power plants needed on the hottest days.

Require ACCA Standards (new and retrofit)

Start With a Solid Foundation

• No matter what type of home, what materials used or where you are located, you need to use a solid foundation of building science.

So you don’t get a big…

Surprise!

Utility

Bill