Category Archives: Energy Use

Passive House Verifier Training Part 1

PHIUSPHIUS (Passive House Institute United States) is one of two organizations in the US that promote and issue certificates for completion of a home that uses extremely small amounts of energy to heat and cool a home. The other organization is an affiliate of the German PassivHaus Institute.

This organization is based in Illinois. The goal is to make passive building principles the mainstream best building practice, and the mainstream market energy performance standard.

prosocoWhat is a Passive House? It is a home that people want to live in. It must be comfortable for the occupants and it must use very small amounts of energy to heat and cool; and for total energy use as well. RIGHT: A Passive House under construction.

Design for a Passive Home emphasizes energy efficient features that are installed during the construction of the home which do not have moving parts. The design relies on all parts to be installed to manufacturers specifications. These details are verified after they are installed.

Smith HouseThe idea is that insulation and air sealing are very cost effective compared to large and sometimes complex new technology in HVAC Systems. Instead of buying the expensive technology, use the money, that would usually spent on upgraded HVAC system, to increase the insulation levels. The details of how much insulation, what type and where are certainly of interested to  the builder and others involved in planning and construction. These details are less important to the home buyer, they just want things to work at a lower cost.

I am writing about Passive House construction since I just finished the training and testing to become a Passive House Verifier with PHIUS. You will hear more about the Passive House concept and how it might apply to any home.

The First Clothes Dryers to Earn the Energy Star Label Now Available Nationwide

ES DryerEnergy Star Press Release Date: 02/10/2015

Contact Information: Jennifer Colaizzi, colaizzi.jennifer@epa.gov, 202-564-7776, 202-564-4355

WASHINGTON –The U.S. Environmental Protection Agency (EPA) announced today that Energy Star certified clothes dryers are now available nationwide through major retailers. At least 45 models of dryers earning the Energy Star label, including Whirlpool, Maytag, Kenmore, LG, and Safemate, are at least 20 percent more efficient and now available at prices comparable to standard dryers. 

“Dryers are one of the most common household appliances and the biggest energy users,” said U.S. EPA Administrator Gina McCarthy. “EPA’s Energy Star certified clothes dryers offer Americans an opportunity to save energy and do their part to combat climate change. By working with industry, we are bringing innovative technology to market that’s good for the planet.”

Clothes dryers consume more energy than any other appliance in the home, and 80 percent of American homes have dryers. But unlike clothes washers, which have seen a 70 percent drop in energy use since 1990, the energy efficiency of most dryers has not improved. If all residential clothes dryers sold in the U.S. were Energy Star certified, Americans could save $1.5 billion each year in utility costs and prevent greenhouse gas emissions equal to the electricity use from more than 1.3 million homes.

The efficiency specifications were developed with extensive input from manufacturers, retailers, the U.S. Department of Energy, and environmental groups. Manufacturers meet the specification requirements by incorporating advanced sensors that more effectively detect when clothes are dry and stop the dryer.

Energy Star certified dryers include gas, electric and compact models. The Energy Star label can also be found on dryers that feature new advanced heat pump technology and are 40 percent more efficient than conventional models. Heat pump dryers recapture the hot air used by the dryer and pump it back into the drum. By re-using most of the heat, a heat pump dryer is more efficient and avoids the need for ducts.
For the complete Press Release:

Energy Efficiency is America’s No. 1 Housing Concern

Home-Insulation-300x225Safety, affordability and privacy – it’s no surprise that these were some of top housing needs identified in a recent national survey of more than 10,000 households. But the No. 1 unmet housing concern, which the Demand Institute that carried out the poll defined as the “satisfaction gap” between what respondents actually have and what they said was important, was not as easily expected: energy efficiency.

Survey respondents were given a list of 52 housing and community concerns and asked to rank them, on a scale of 1 to 10, by how important they felt the issues were and how much their current home satisfied these needs. The result: 71 percent of U.S. households polled placed a great deal of importance on energy efficiency, but only 35 percent felt their homes were very energy efficient with low monthly utility costs (the respondents making up percentages answered these questions with an 8, 9 or 10 ranking).

Based on these numbers, energy efficiency was the housing concern with the largest gap between the rates of importance and satisfaction – beating out consumer needs and wants for updated kitchens, storage space, safe neighborhoods, affordability, landlord responsiveness and more.

Why the strong desire for energy-wise homes?

“Utilities are a significant and regular part of households’ budgets, and spending on utilities has risen more quickly than overall consumer spending – 56 percent vs. 38 percent growth since 2000,” said Louise Keely, president of the Demand Institute, a nonprofit think tank jointly created and operated by Nielsen and the Conference Board to monitor consumer demand.

To read more of this report:  The Demand Institute Poll on Triple Pundit.

Millennials Seek Smaller Homes, Energy Efficiency, Won’t Sacrifice Details

Originally Published on the NAHB Website
http://nahbnow.com/wp-content/uploads/2015/01/507029289.jpg

Laundry Room

The survey says: No laundry room = no sale.

 

As Millennials begin to enter the home buying market in larger numbers, homes will get a little smaller, laundry rooms will be essential, and home technology increasingly prevalent, said panelists during an International Builders’ Show press conference on home trends and Millennials’ home preferences last week.

NAHB Assistant VP of Research Rose Quint predicted that the growing numbers of first-time buyers will drive down home size in 2015. Three million new jobs were created in 2014, 700,000 more than the previous year “and the most since 1999,” Quint said. At the same time, regulators have reduced downpayment requirements for first-time buyers from 5% to 3% and home prices have seen only moderate growth.

“All these events lead me to believe that more people will come into the market, and as younger, first-time buyers, they will demand smaller, more affordable homes,” Quint said. “Builders will build whatever demand calls out for.”

Quint also unveiled the results of two surveys: one asking home builders what features they are most likely to include in a typical new home this year, and one asking Millennials what features are most likely to affect their home buying decisions.

Of the Top 10 features mentioned by home builders, four have to do with energy efficiency: Low-E windows, Energy Star-rated appliances and windows and programmable thermostats. The top features: master bedroom walk-in closets and a separate laundry room.

Least likely features include high-end outdoor kitchens with plumbing and appliances and two-story foyers and family rooms. “Consumers don’t like them anymore, so builders aren’t going to build them,” Quint said.

When NAHB asked Millennials what features fill their “most-wanted” shopping list, a separate laundry room was clearly on top, with 55% responding that they just wouldn’t buy a new home that didn’t have one.

Storage is also important, with linen closets, a walk-in pantry and garage storage making the Top 10 – along with Energy Star certifications. In fact, this group is willing to pay 2-3% more for energy efficiency as long as they can see a return on their power bills.

If they can’t quite afford that first home, respondents said they’d be happy to sacrifice extra finished space or drive a little farther to work, shops and schools, but are unwilling to compromise with less expensive materials.

A whopping 75% of this generation wants to live in single-family homes, and 66% prefer to live in the suburbs. Only 10% say they want to stay in the central city. Compared to older generations, Millennials are more likely to want to live downtown, but it’s still a small minority share, Quint said.

Panelist Jill Waage, editorial director for home content at Better Homes and Gardens, discussed Millennials’ emphasis on the importance of outdoor living and that generation’s seamless use of technology, and how those two trends play into their home buying and home renovation decisions.

Because they generally don’t have as much ready cash or free time as older home owners, Millennials seek less expensive, low-maintenance choices like a brightly painted front door, strings of garden lights and landscaping that needs less watering and mowing, like succulent plants and larger patios.

They’re also very comfortable with their smartphones and tablets, and increasingly seek ways to control their heating and air-conditioning and security and lighting as well as electronics like televisions and sound systems from their phones. “They want to use their brains for other things, not for remembering whether they adjusted the heat or closed the garage door,” Waage said.

Get more details about the NAHB survey in this post from Eye on the Economy.

I emphasized the two comments about Energy Efficient Features NAHB found.  If you would like help in addressing these in a cost effective manner for your buyers, Call The Energy Guy!

Who Is Building an Igloo in Wichita?

It all started on Twitter. @AIAWichita @moongodess316 and I had some fun over building an Igloo.

Igloo1

I saw this Tweet and immediately thought of a quote from Dr. Joseph Lstiburek: “The Igloo was the First Passive House.” Joe is an engineer by training and has been working with buildings, insulation and energy use for over 30 years. His Building Science Corporation, based in Massachusetts, conducts research and is one of the best sources of verified information on building energy efficiency in buildings.

So I tweeted back.

Igloo2

What is the difference between a Passive House and a regular house? What is the buzz all about?

Strawbale

When you build a home you can use lots of insulation to reduce the amount of electricity and gas to heat and cool the home.

GSHP Diagram

You can use a lot of high tech equipment to reduce the amount of electricity and gas to heat and cool the home. You can also do both.

PHIUSThe Passive House was developed in Germany, so you see it referred to at times as Passiv Haus.

We know that insulation works and that more insulation works better. As the cost of electric and gas goes up, it makes financial sense to add insulation to a home or business. In 2000, the local cost of Electricity was 8 – 9 cents, the recommended level of attic insulation was R-30. Today the cost of electricity is 12 – 13 cents and the recommended level of insulation is R-49.  Both have increased about 1/3 in 1 years. We also know that air movement, cold drafts, makes people uncomfortable and causes insulation to not work as effectively.

Round Metal TubeThe sources of air entering a home are usually related to corners. Since we like living in buildings that have square corners there are a lot of them in a home. Windows do not usually cause air leakage. How they are installed can cause air leakage. The age or the quality of the window does not seem to matter when installation mistakes occur.

PHIThe primary requirements for a passive ouse certification are based on Energy Usage and creating a structure that needs very little energy for heating and cooling. These standards are effectively summarized with these two limits.

  • Total primary energy (source energy for electricity, etc.) consumption (primary energy for heating, hot water and electricity) must not be more than 120 kWh/m² per year (37900 btu/ft² per year)
  • The building must not leak more air than 0.6 times the house volume per hour (n50 ≤ 0.6 / hour) at 50 Pa (N/m²) as tested by a blower door.

In our Twitter Conversation, Angee McBustee tweeted a question about how is building a igloo in Wichita. Then I responded with the offer to run the blower door test. As you can see from the primary requirements the Blower Door result is very important to a passive house.

Igloo4

How good is a Blower Door Test of 0.6, as required by Passive House? Energy Star New Homes require a Blower Door Test of 5.0 or less. New homes in Wichita routinely test around 4.0. In the blower door testing, lower is better.

For standard construction, I have tested several homes at 1.0. There is one home that I have tested with a lower result. A custom home in Butler County is under construction. They had me do a Blower Door test after it was sheathed. No insulation, no drywall. The test result was 0.62. We were able to find several leaks using biometrics and the infrared camera. That was last September. I returned in December to test it a 2nd time, the results were so low, that I didn’t have the right test equipment to measure the result. I would estimate it to be in the 0.30 range. I now have the equipment to test a home like that.

In February, I have been accepted for training and certification as a Passive House Rater/Verifier. Christine is building the home in Butler County, I want to thank her for the push to obtain this certification.

In the Twitter Conversation, AIA Wichita came back and said they were posting an information tweet.

Thanks to Angee and AIA Wichita for a nice idea for a Blog Post.

Passive House Work in Wichita

In the last two weeks, two national groups that certify construction for Passive House Standards conducted their annual conferences.  PHIUS was held in Portland, OR; and PHI was held in Maine. Locally, I have completed the first of 3 planned Blower Door tests for a passive concept home under construction; discussed the planned construction with another builder to start later this year; and discussed passive building concepts with another builder planning his first homes next year.

PassivhausDarmstadtKranichstein-300The Passive House concept started in Germany, with construction starting in 1990 on several homes. In German, it is Passiv Haus,  PHI for Passiv Haus Institute.  The standards followed by this concept require an attention to detail in design and construction of the thermal enclosure.  Historically referred to as the envelope, the thermal enclosure involves the exterior bottom, sides and top of the structure.

  • Higher than commonly used levels of insulating material,
  • windows meeting specific standards and very
  • Effective work on air sealing
  • Attention to the Solar Orientation of the home to maximize the use of solar heat in the winter

PHIThis results in an extremely low energy bill.  How low? In the Wichita area, this would translate to an $88 – $110 annual natural gas bill, instead of $500 – $900 bills that I routinely see on Home Energy Audits.

The passive term comes from the idea of using insulation and construction techniques to create a significant energy savings instead of relying on fancy machinery to create that savings. Dr. Wolfgang Feist of Dahrmstat, Germany founded the Passiv Haus Institut in 1996.

Smith HouseThe passive house concept arrived in the US in 2003.  Katrin Klingenberg, a licensed architect in Germany, She built a home meeting these standards, 2 hours south of Chicago.

 

Most countries have a local organization that trains and certifies homes and commercial buildings to the Passive Standard. Yes, passive concepts apply to buildings other than homes. These groups train people to apply and measure the standards. They also review the reports on specific buildings and accept or deny actual certification for a specific building.

PHIUSIn the US, this organization has been known as PHIUS.  Passive House Institute, US. Ms Klingenberg has been the leading light of this group, which was founded in 2007.  There are some things in each country that differ from the original German model of Passiv Haus.

The experience of the professionals working with PHIUS in the US has resulted in some changes to how the concept is applied in the US. For example, the metric units used in the German (and most others in the world) have been translated to the Imperial units used in the US. The collaborative nature of US business groups has been essential to moving the passive concept from being used by a relative few to becoming a market force in the US.

Because these adaptations by PHIUS to the US market, were not acceptable to the original PHI, a divide between the approaches has occurred in the US.  It is mostly technical, and both groups agree the concept is still primary.  Effective building resulting in low energy use.

Some claims have been made that these concepts are two expensive for the US market. The original Passive House in Illinois was built at a 2003 cost of $94/ sf.  That is very favorable with current US construction costs. Since additional people are using the concept and the resulting products that manufacturers are producing, the mass production will bring some drop in costs.

If you wish to read more about the two national conferences for both the PHI and the PHIUS organizations that just finished, you may use these articles.

The 9th annual North American Passive House Conference (PHIUS)

Report from the Passive House Conference in Maine

I will keep you updated on activity in this area about Passive House building activity, as it progresses.  Three projects is a great start.  I’m glad that builders are willing to try new concepts and that home buyers are willing to step up and buy these homes.

In the introduction of this post, I mentioned a house under construction with the Passive House concept. I conducted the first of 3 Blower Door Tests last week.  This test was after the framing and exterior sheathing was completed.  Insulation, plumbing, electrical and trades had not started.  The second test will be in a few weeks after these trades have done their initial work and put holes in the enclosure.  Electric wires, plumbing, HVAC and other necessary conveniences of our lives will be installed in passive concept homes. The third test will be done at the end of construction.

The PHI/PHIUS standard for Air Infiltration as measured by the Blower Door Test is 0.60 –  The current 2012 recommended code requirement for this is 3.0 — Wichita/Sedgwick County does not have an energy code in place, but the Kansas City area does. They enforce a 5.0 standard.  Typical homes built from 1980 and prior are in a range of 10 – 38 from my testing.

The goal of the builder on this passive concept home was to reach 1.5 on this first test. Then using the Infrared Camera to find areas to caulk, and fixing the penetrations mentioned above, have the next test come in lower.

Blower Door62This test, actually came in at 0.62 —  almost the standard.  Much better than the expected 1.5 .   While the blower door was running, the Infrared found some places that could be fixed.  Dan, the carpenter, was right there with a caulking gun.  We also found some leakage with biometrics. A back of your hand that is wet, will show you extremely small amounts of air movement.  Most builders like to use expanding foam to seal the actual window to the rough opening.  We found some of these foamed openings were still leaking. Again the caulking gun was a good answer.

 

A Healthy Home Part 3 — Well Ventilated

Fresh AirA Healthy Home is well ventilated.  Everyone knows fresh air is important. This should be easy.  Well ventilated in more than just bringing in fresh air. The concepts are certainly easy, the details on the other hand take some thought and planning.  A new home ventilation strategy is fairly straight forward to design and implement. An existing home needs the input from the occupants and good analysis to address the problems. An effective ventilation strategy should address these issues in either new or existing homes.

  • Remove humidity, odors,, or significant problems from specific areas.
  • Remove stale, musty or other objectionable air.
  • Allow the occupants to choose fresh air sources that can be filtered or treated in other ways
  • Allow the occupants to choose to open windows when outside weather is appropriate
  • Allow the occupants to operate a system that can provide the amount of fresh air, to the appropriate places, in adequate amounts when needed
  • Provide fresh air when the outside air creates potential problems, such as Ragweed season or when other allergens are active
  • Provide air movement within the home, without the use of the expensive blower on the furnace or heat pump.
  • Allow minimal use of heating or cooling equipment during the shoulder seasons, when temperature changes are minimal, while keeping the home comfortable.

Billings QuoteHow much fresh air is needed?  Going back to the 1890’s, the number has been pegged at 30 CFM (cubic feet per minute) per person. This number was validated in a number of different studies and with the public health authorities in larger cities, dealing with large apartment buildings and recurring respiratory diseases.  I was pointed to the quote at the left by Allison Bailles. he located the original book on Google Books, page 20.

Beginning in the 1930s, research into changes in building techniques began to show the optimal number was closer to 15 CFM per person.  Some of the changes in construction included the increased use of forced air heating, moving from balloon framing to platform framing, increasing square footage, and the use of insulation in walls and attics. The formula changes from time to time and everyone has an opinion on details. The common point remains, fresh air is needed in every house.

Part of the Ventilation is removing air with a problem. Where is that?  Humidity is found in rooms that use hot water and basements.  Showers, tubs and cooking are the large sources of humidity.  The smells from food preparation and cooking can be very mouthwatering.  When the meal is finished and the refrigerator is full, the lingering smells become odors.  The answer is some spot ventilation in these areas. If your basement has a humidity problem, you can tackle that with a fitted sump pump cover to contain the humidity, and work to eliminate any water seepage.

vent fanSpot ventilation is a window that opens and an exhaust fan. The size of these fans is part of the formula that is specific to each home. The features of the fan are common to all homes.  It must be quiet. Builder grade fans are noisy. Noise in fans is measured in ‘Sones’. The Sone is a linear measurement of noise, compared to the decibels used by OSHA and others which is an exponential measurement.  Linear is better for quiet sounds, and decibels is better for loud noises. Fans should be less than 3 sones, and preferably less than 1 sone.  Reasonably priced fans are available that rate a 0.3 sones. A 1 sone fan is very quiet.

UnknownFans are certified for air flow and noise levels by the Home Ventilation Institute. HVI certification is very common and includes both the Sone rating and CFM rating.  When installing a fan, you must consider the duct losses that will occur in meeting the required air flow.   The rates for bathroom air flow  are 50 CFM, and 100 CFM for a kitchen.  Do not expect to buy a 50 CFM fan for a bathroom and connect it to 6 or 8 feet of duct work, and obtain 50 CFM.  I have measured 30 CFM routinely in these set ups.

Most people understand that various parts of their body are just a part of the whole.  If you start some type of therapy, there may be a side effect. Physical Therapy starts and you end up with some sore muscles, aha!  Side Effect!  Start a therapy for cancer and your hair may fall out, aha! Side Effect!  Your home works the same way.  Each part is just part of the whole. Change something, aha! What is the side effect?

House-System-imgAll of the items in the list above are part of the whole. For an existing home, some specifics of that house may indicate concentration on one or another of those areas.  A home built in the 1920’s will benefit from a different approach then a house built in the 1980’s.

A new home should have the ventilation system that meets the general points above.  The natural ventilation provided when windows and doors are opened, or the mechanical ventilation system that allows filtered and perhaps treated fresh air brought in from specific places and in specific amounts, allow the occupants to make the system work as they need.

 

This post is part of a Series on A Healthy Home

 

 

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 House Part 1b: How Dry is Dry

In the first installment of A Healthy House, we looked at water issues.  Specifically, water from the outside of the home.  Most of this type of water is directly from what the weather refers to as ‘precipitation’, or rain and snow.  Even the ground water we looked at were related to rain and snow.  There are other types of water issues.

pipe_leakFirst would be a plumbing problem.   You can have a leak in a water pipe, or a sewer line.  I know, sewer lines generally do no leak, they slow down, or plug up and then back up.  Either way there is water in the house, and someone is cleaning it up.

Many plumbing leaks like this or sewer problems are an ongoing maintenance issue. Not much can be done during construction.

Situations like the drain line, getting stepped on and thus the floor drain is the highest spot in the floor is a construction issue.  It takes all the trades to help finish the building correctly. The plumber may have done it right, only to have someone else step on the line.

A nail accidentally driven next to a supply pipe, may cause a problem later. If you have copper, 2 dissimilar metals touching will eventually cause a leak.  A nail next to a plastic line that moves, can also create a leak. You may find great work in a home and good, conscientious, plumbers, drywall installers, electricians and others. Sometimes these defects are hidden, like the tip of the nail inside a wall. So maintenance becomes an ongoing effort.

daltile-Bath-Accessories01Thoughtful design can help.  Specifying hard surfaces for areas within a few feet of tubs, showers, toilets, sinks and laundry facilities is important. Most leaks, spills and accidents will occur in these areas. An easy to clean surface that doesn’t hold the moisture is essential.  Carpet has it’s place, just not near water. Some floor coverings such as linoleum or cork type flooring may also not be appropriate for these areas. (Image to the right is courtesy of DalTile.)

 

Hard SurfaceAppropriately located floor drains can help.  Use of appropriate materials in the floor structure is a good thing. Most homes in this area have a basement, meaning a wooden subfloor is under and of these facilities on the main or upper floors.  The proper type of sub floor in these areas is crucial to keeping the home dry. It is also helpful in drying, when the floor does get wet and not encouraging mold growth, as many types of common building materials.

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

Using One HVAC System for Two Areas

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

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

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

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

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

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