Building Science Summer Camp 2013

August 7, 2013

It’s that time of year again where some of the greatest minds gather in Massachusetts for The Westford Symposium on Building Science, or better known as Building Science Summer Camp.  This event is hosted every year by Joe Lstiburek, PhD. PE and his wife Betsy Pettit, FAIA.  This camp is an all-out building science geek fest where some of the top researchers present studies and new building products and systems in an effort to help design and build more energy efficient and healthier homes.

As this is an invitation only event, I am left glued to my seat to follow and decipher the presentations live, 140 characters at a time from its 430 attendees by following the twitter hashtag #bscamp.  However social media has increased access to this event yet again.  A big shout out goes to Michael Anschel and Stephen Davis for broadcasting live the now famous tweet chat in Joe’s crawlspace via Ustream. Follow their channels here & here.  Thus if you have any interest in the latest building science research, I encourage you to watch last nights crawlspace interview of Joe and to follow the #bscamp twitter chat as today is the last day of the symposium.

Video streaming by Ustream

 

Building Science Sunday – Knowledge & Practice

February 17, 2013

I recently read an article (here) from Dr. Joseph Lstiburek.  It wasn’t his overly technical type of writing diving deep into building science, it was more of his personal story of how he began his career and some of the great building science minds of the 60’s & 70’s that he had the pleasure of meeting and learning from.  Yes I did write the 60’s & 70’s.  Building Science is not a new thing, the topics Joe has been presenting have been done before, but no one was doing it and to this day building science is still a mystery to most of the design and construction industry.

Now what I took from that article is not the name dropping of who he met early in his career, but more of what he did with those connections and new found knowledge.  He applied it, he took what he learned from those individuals and put it into his then home building practice.  And to this day he is still refining some of those early construction practices. Read the rest of this entry »

Potential Hazards of Conventional Water Heating

November 29, 2012

Beginning May 1st, 2013 80 AFUE, also known as induced draft atmospheric furnaces will not be installed in cold climates, such as here in Ohio (article) as determined by the US Department of Energy (DOE).  The new minimum AFUE requirement is 90 AFUE, which means the unit is a sealed combustion unit.  All combustion is contained inside of a sealed chamber and a powered vent fan is used to exhaust all of the combustion gases.  The DOE reason for the new change is to set a new higher minimum efficiency standard; however I like this new requirement for safety reasons.  It practically eliminates the potential of backdrafting.

I would like to see the same kind of requirement for water heaters.  In my professional opinion atmospheric water heaters do not belong in today’s homes, even the older ones that are getting weatherized.  New homes and even older ones that are getting sealed and insulated are getting tighter, and this could have a negative effect on the atmospheric water heater.  How do you ask?  Well as we tighten things up we have less air infiltration into the home which means fewer holes to allow air to replace the air that is being pulled out of the house by running bathroom or kitchen exhaust fans.  Because the adage is for every bit of air you pull out of the house, it has to be replaced.  Why does this mater, how does it affect your water heater?  Well your water heater has a 3-4”, sometimes larger hole to the outside known as the flue.  So when you turn on your exhaust fans or even use your fireplace, this is the path of least resistance and can be a harmful one pulling combustion gases and carbon monoxide back into the home.  Because when your water heater is running, it relies on the buoyancy of hot air to travel up the flue pipe to exit the home and it does not take much to pull that hot air back down the pipe along with the carbon monoxide.

Read the rest of this entry »

Why I Hate My Job

September 23, 2011

Well not much really.  But let’s be honest, would you have even had interest in reading if the title was “Why I Love My Job”?  So this is basically my year in review of working for Conservation Services Group performing home energy audits and to share a little more about my job that I did not get to share during the panel discussion at the AIA Ohio Valley Region convention in Dayton, OH last week.

So let’s stick with the title and what I do not enjoy about my job.  First, 90+ degree days, it makes for very uncomfortable working conditions as the attic is 100+ degrees.  However that is a condition of the job and is only an issue of comfort.  The hardest, as well as worst part of the job is delivering news to customers as I was reminded of today.  First is the customer that already has decent levels of insulation and based upon calculated paybacks and program goals do not qualify for very attractive incentives for energy efficiency improvements through the utility rebate program that we do work for.  I get a lot of eye rolling, but that is easy to handle, just lots of additional table talk which can add a lot of time to an appointment that only allows 4 hours to inspect, test, generate a report and present it to the customer.  However the absolute hardest part about my job is telling a customer, especially an assisted customer that is getting free work done that cannot have any air sealing or insulation work done until combustion safety issues have been resolved such as back drafting water heaters, or high CO levels.  This can really tug on the heart strings when you are in a home that has little to no insulation and you can see they would greatly benefit from lower utility bills and truly cannot afford to make some of the repairs necessary, yet their income level is not low enough to qualify for weatherization assistance that would actually make these repairs.

Read the rest of this entry »

Kitchen exhaust really sucks!

March 23, 2011

Range HoodI think the title explains itself.  Commercial range hoods or downdraft exhaust are becoming popular in new homes and kitchen renovation projects.  You know they look cool or have the ability to hide in the counter top, and man can they suck.  Hold your hair piece around some of these because you could lose it.  They actually pull so much air out of the house, that they cause very harmful conditions in the home.  And I have been conducting energy audits on more and more of these homes lately and leaving with not so happy customers.

The issue that these exhaust units create is that they are pulling so much air out of the home that air has to come back into the home somehow and this is causing standard atmospheric water heaters and the less efficient furnaces that are still in operation in lots of homes to backdraft.  So anytime you turn on the exhaust, it actually pulls the combustion gases from your water heater into the home increasing ambient levels of carbon monoxide.  And this situation can occur in any old, new, large, and leaky home.

I mention not so happy customers because when I come across this condition, all incentives from the local utility to make efficiency improvements are halted until the back drafting issue is resolved because we don’t want to tighten up a home and make the conditions worst.  Although this is not really a green building issue, it is just that green builders and designers who look at how the house works as a system takes these kinds of issues into consideration.  Therefore here is a preview of a great article from GreenBuildingAdvisor.com on ways to prevent the back drafting from these high cfm rated exhaust fans that any homeowner, architect, designer & builder/remodeler should read if considering one of these units.

Makeup Air for Range Hoods

If your kitchen has a powerful exhaust fan, it may be pulling air down your chimney or water-heater flue

Most homes have several exhaust appliances. These typically include a bathroom fan (40-200 cfm), a clothes dryer (100-225 cfm), and perhaps a power-vented water heater (50 cfm), a wood stove (30-50 cfm), or a central vacuum cleaning system (100-200 cfm). But the most powerful exhaust appliance in most homes is the kitchen range-hood fan (100-1,200 cfm).

Every time an exhaust fan removes air from your house, an equal volume of air must enter. The air that enters cracks in a home’s envelope to replace air that is exhausted is called “makeup air.” Two trends affecting makeup air are causing increasing problems for homeowners: homes are getting tighter, and range-hood fans are getting more powerful.

So where does a powerful range-hood fan get its makeup air? If the house doesn’t have enough random air leaks around windows, doors, and mudsills, the makeup air is often pulled backwards through water-heater flues or down wood-burning chimneys — a phenomenon called backdrafting. Since the flue gases of some combustion appliances can include carbon monoxide, backdrafting is dangerous. In some cases, it can be life-threatening.

Continue reading the article at GreenBuildingAdvisor.com