MA: Completing a Total Leakage Duct Test

     If you have not been asked to complete a duct test by your local Massachusetts Inspector, it is just a matter of time before you are surprised by this additional code requirement.  Despite some push-back from city and town Inspectors, all of MA is required to test new or altered duct systems - with varying enforcement, and held to various degrees of leakage rates.  All of MA adopted the 2009 International Energy Conservation Code (IECC) back in 2010.  Some cities and towns wished to be eligible for the available funding from the Green Communities Act, and voted to adopt a Stretch Code - known to most contractors as the more stringent regulation.  It pays to know which towns you are working in, and their permit structure, to avoid losing what could amount to be a significant part of your profit on these jobs.
     If you are working in most of the cities and towns across the state, you are able to complete your own "Total Leakage Duct Test". If the town adopted the Stretch Code, third-party testing by a RESNET Certified HERS Rater will be required.  This means that even if you went and got your certification, you could not test your own jobs in these towns anyhow.  Don't worry though, a HERS Rater is needed to rate the home or addition, and their testing is not exclusive to your duct system.  This means a rating is needed when a Building Permit is pulled, a change to a structural wall.  In other words, if the testing does not fail due to your duct system, the general contractor will be paying for this rating.  For all other cities and towns across MA, you can complete your own testing and no certification is needed.  In fact, there are no certifying bodies for duct testing that I am aware of.  Many organizations like BPI or RESNET will offer training, but no certification.
     Anyhow, take a look at the attached document I created, I think it will help those that are just becoming involved with Duct Testing in MA.  Also, please share your experiences with the local city and town requirements by commenting below - nobody likes to be surprised!

Home Performance: Combustion Powered Ventilation?

     I sat in a review class today prior to my Building Performance Institute (BPI) written exam, and I heard the first explanation I have ever seen as to how a basement would become more humid after replacing a furnace.  So, I have to share with as many folks as possible in our HVAC field.  You see, a Category I furnace: naturally vented and 80%+ AFUE, takes the needed air for combustion from the basement.  Once burned, said byproducts go out the chimney; the draft (or draft inducer) pulling the needed combustion air, and with it moisture out of the home.  What happens when a responsible contractor identifies an opportunity to save fuel and sells the homeowner a sealed combustion 95%+ AFUE furnace?  Now, that combustion powered ventilator was removed from the basement, leaving the high moisture content air to sit there.
     The solution?  Add ventilation.  But, one does not know what one does not test.  How do you know if you actually need to add ventilation to a home that has had the natural conditions changed, and how long does that fan need to operate?  During the retrofit furnace replacement, the HVAC Contractor more than likely changed the way the home performs as a system.  If an air-conditioner was not working correctly you would have to send a technician out to test it, right?  This is where a Home Performance Contractor, or Energy Auditor, could identify this ventilation need - or lack there of.  You don't know what you don't test, and since you installed a sealed combustion furnace you are more than likely not going to kill anyone; but this does not mean you're not killing the house!  There is some simple math that can be completed, coupled with a blower door test and you can know if you must add ventilation to the home.
     I remember a lot of local HVAC contractors up in arms last year about BPI certifying heating professionals.  Instead of complaining, I would highly recommend these guys jump on board.  As an HVAC professional for all of my working life - granted that is "only" the last 15 years, I can contest that is is much easier for an HVAC technician to become a Building Analyst Professional than the other way around.  There is some training involved, but believe it or not these guys have some real important information to share that just may save your business one day - or at least help you sleep at night!  Check out their standards, easiest way to learn something new/free this week:               http://bpi.org/standards_approved.aspx

Dirty Socks in the Attic?

     Last week I heard a great idea from a great HVAC contractor - the two kind of go together don't they?  It is an easy answer to a common problem in our industry: the dirty sock syndrome.  I have heard of many ways to avoid condensation forming over the winter in ducts and on coils, including but not limited to: operating your fan constantly, installing a fan cycling thermostat, and use of a UV light.  Unfortunately, all of these solutions are not demand based, meaning they will operate whether they are needed or not.  For those of you that know me, you know that I have crossed over to the dark side of Energy Efficiency - and I can't sleep at night if I installed one of these solutions.  Don't get the wrong idea, these are solutions and will stop that smell first thing in the Spring.  But, how much energy did it take to get you there, and how much was the total investment for the homeowner?  What if I told you there was a simple fix that would cost you, the contractor, about $50?  Got your attention?
     In the Northeast we have a lot of boilers, and I mean a lot!  Usually, this means a lot of ductwork must be added in the attic - for that all important conditioned air in the Summer.  Unfortunately, this creates quite the "chimney effect" and phantom airflow issues all winter.  Most homeowners are aware that they need to close the supply registers, but returns are often ignored since there is no easy way to close them.  I used to use a white trash bag to cover the air filter, but you can see where this is leading when the homeowner forgets to call you for maintenance by late May.  So, instead of closing off the registers, why not cycle the fan on a demand basis?  Mold, mildew, and that dirty sock smell is created by condensation and standing water in the ducts and coils over the winter.  In order for condensation to form, the relative humidity in the ductwork must reach 100% Rh, right?  That is the humidity when it is raining outside, 100%.  For sake of simple math, and to avoid the psychrometric conversation, I am going to leave out dew points and surface temperatures.  The easiest solution there is to just insulate your ducts to code.  Anyhow, if you install a De-humidistat to close the Fan circuit, or 'G' on your Integrated Fan Control, than the fan will cycle on (in most cases on your lowest speed) prior to condensation forming in your ducts and coils.  The key point here is that it will then shut off when the humidity reaches the acceptable level that you set it for.  So, you may get a short span of cool air being blown around that zone, but doesn't that beat the poor indoor air quality and men's locker room stink in the Spring?  Not to mention less energy use (Kwh) to get you there!

Special thanks to Jeff Rossi of RER Fuel for sharing this week's tip.  Jeff knows this works because it was a solution for his own house!