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I work with a C.A.O. here in Ohio under the W.A.P. now that D.O.E. requires implementing ASHRAE 62.2 2010 as of PY 13 and 62.2 2013 in PY 14 my concern is accomplishing this correctly.
The required mechanical venting calculation is pretty much cut and dry with the availability of calculating programs thru R.E.D. and alike. So now I have my required cfm, do I really want to install an exhaust fan system in every home, no, not with depressurization limits, questionable infiltrating air quality source and so on.
How about a in line supply air system in the return duct to the furnace, maybe, is it a central return system if so where is it located in a hallway ceiling or on the wall in the living room ? On a branched return system, I might be wrong here but,wouldn't the path of least resistance for the in line supply air be over the heat exchanger? If that is true, wouldn't there be some kind of thermo shock to the heat exchanger having 20 or 30 degree or colder air blowing over it for any period of time then the burners lighting off, resulting in a premature failure of exchanger from expansion/contraction or possible excessive condensation?
I'm not up to speed on the other options such as ERV, HRV just the basic concept, that is next on the to do list.
I understand Wisconsin's W.A.P. has been doing this, ASHRAE 62.2,since 2005 so I,m just looking to start a conversation with anyone, especially associated with W.A.P. and familiar with the limited Health and Safety funds available, on how they approach and implement this standard, or any studies done on the energy, efficiency or comfort level penalty, along with the other side of the coin, improved heath via fewer E.R./ Urgent Care / Hospital reports of lower respiratory/health issues.
A lot of questions requiring some lengthy answers, but I’ll try to keep them concise. In NY, we are in the process of switching from 62.2-2010 to 62.2-2013. While it is an improvement in many ways, there are still some shortcomings, some of which have been discussed in other threads.
For an exhaust-only ventilation strategy, most folks are simply installing a 50 CFM fan in the bathroom with a ventilation timer switch. This typically doesn’t increase CAZ depressurization because the fan simply runs longer, not stronger.
Of course, exhaust-only ventilation doesn’t really exist, it’s actually exhaust ventilation coupled with infiltration. After air-sealing, you’ll want to determine where the remaining infiltration is located to ensure the exhaust ventilation is only pulling in fresh air. If you’re unable to control the infiltration source, then a supply air system or balanced ventilation system such as an HRV would be in order.
An outside air duct connected to a furnace return does not cause as much temperature shock as you might think because the incoming cold air is mixed with and diluted by the larger supply of return air from within the house. Still, I’d be concerned about using this method with an 80% furnace with a clamshell heat exchanger.
During mild weather, the air handler may need to turn on to provide fresh air ventilation, but there is no call for heat. It is in this scenario that cool air coming from a heat register will feel uncomfortable. Running the fan at low speed will minimize the feeling of a cold draft.
The larger challenge is controlling the amount of fresh air that comes in. An intake zone damper controlled by a ventilation timer works initially, but may not always be consistent. The timer is set based on the CFM flow with the air handler on. Clients closing heat registers in unused rooms can reduce overall airflow and thus reduce fresh air intake CFM. Supply air ventilation to the return side of a furnace typically pressurizes a home. This can work to help prevent bad air from being sucked into a home, but it can cause warm, moist air to be forced out through the building enclosure with undesirable results.
One of the challenges has been the increasing requirements to address Health and Safety issues without an increase in funding to cover the added costs. As you do more homes, you’ll be able to meet the 62.2 ventilation requirements more cost-effectively.
Personally, I’d like to see two separate funding streams; one for energy efficiency, the other for Healthy Homes. The WAP agencies are in an ideal position to treat a house as a system and determine how best to integrate health and efficiency to create an optimally performing home at a minimal cost.
As to research, a web search on health and ventilation brings up plenty of articles and studies.
So many questions....
I have recently taken the time to study the teachings of Raymer, Karg, Lstibureck, Armanda and Sterner.
My conclusion is that the challenge is not understanding the formulas, but rather what to do in a WAP site.
I have seen a range of installed measures and an even wider range of costs associated with those efforts.
The bottom line is cost.
I agree with the concept that Health and Safety costs are independent of conservation costs in principle, but associated diagnostics and test out costs are significant.
What I am hoping to accomplish is developing a "Best Practices" approach to installing low cost ASHARE compliance.
There has certainly been enough work done to this point to provide the case study needed to assess which measures are best. So what's the big secret?
Granted every site is different, but what is needed is a simplified approach.
Wasting time and funds trying to tweak existing ventilation equipment is costly and produces only marginal results.
Cutting holes in roofing materials is an unnecessary liability.
I would like to see a packaged assembly that can be installed in 75% of the WAP sites to address this requirement.
Think Fan in Can or Radon exhaust equipment.
Remember 1 CFM in 1 CFM out, regardless of any other envelope modifications.
The package I am seeking would contain a remote exhaust fan/motor, switching and makeup air inlets that could all be installed on a first floor level and sub-space and exhaust at the sill plate level, at a cost of less than $500.00.
Then, I think the we can start to approach this compliance effectively and successfully.
Am I dreaming?
Just a quick comment since I did not see it mentioned. A 100cfm H/ERV should deliver 100 cfm of fresh air. But a 100 cfm supply or exhaust only fan will deliver about half that amount. James, you state "1 CFM in 1 CFM out", but with supply or exhaust only the house pressure is changed and half of the air exchanged comes from a reduction in the natural air flow. To get 100 cfm with exhaust only you would need a 200 cfm fan. In a tight house the 50% reduction disappears once the neutral plane exits the envelope.
Thanks for the feedback Bud.
I understand the science that you are referencing.
My point is that in WAP, the use of H/ERV is generally cost prohibitive as are most duct modifications.
My goal is to provide the low income population with a simple, cost effective approach to this compliance.
The health benefits to proper ventilation are well documented.
Yes, the likely fan choice for universal application would be 200CFM+ with 6" in and out and the controls would be set accordingly. I see exhaust as the primary solution and suggest make up air inlets as the best practice for controlling infiltration source. Obviously, location is critical in reference to neutral plane.
I was hoping that someone out there would recognize the opportunity to provide and install a simple equipment solution for the vast majority of the WAP sites.
I recognize that this may limit the revenue that could be rung out of this compliance, but I am speaking to WAP needs only.
There are as many holes in 62.2 as there are in the average low income residence.
Let's stop pretending that we can control behavior and install the appropriate equipment for this application.
Rocket science and limited funding is a very bad formula.
I am very interested in hearing from the Manufacturers on this subject.
The Mfg. that nails this will make a bundle!
Is anybody listening?
Thank you Mr. Raymer,
your feedback is very much appreciated and helpful.
In respect to the gentleman from Ohio's questions, and my experience in WAP sites, I continue to pursue equipment recommendations that are suitable for WAP use.
Let's talk about some other things that we cannot control and some assumptions in existing homes.
We cannot control the fact that the typical WAP site may have either none or poorly constructed and installed ventilation devices.
The typical site has minimal electrical circuits options.
The typical site has has lead paint or asbestos laden plaster in the walls and ceilings.
The typical site has deteriorated roofing materials and lead paint on the exterior surfaces.
We cannot assume that client education results in the increased use of the existing ventilation devices or operating windows.
We should not assume that a continuously running bathroom fan is a solution despite the mathematical qualifications.
We cannot control the effective operation of installed ventilation equipment or the life expectancy of timers and motor controls.
Does anyone really believe that a 34 CFM continuous is providing significant health benefits throughout the building?
It was OK to talk about going to the moon before the rockets were built.
It is not OK to mandate compliance with a standard without a reasonable examination of the material resources and costs.
DOE has done considerable research and set new goals for standardized work specifications.
My hope is that an equipment specification can be developed that addresses the need to install ventilation that is functional and cost effective in WAP homes.
Any approach that simply suggests tweaking existing of installations is not necessarily producing good results in my experience.
Again, keeping it real, I respect that every site is different, but a huge percentage of the WAP sites are single story mobile homes, ranches and capes. What is needed is a cost effective approach to this housing stock and that will allow additional resources to be spent on more challenging situations.
I am confident that the solution to controlling costs and getting this very critical measure installed in WAP homes, is in the equipment choice and installation guidelines.
Please note that WAP has done a remarkable job at developing and implementing strategies for air sealing and blowing insulation and there are countless homes that need this remedy immediately.
I am really disappointed that the ASHRAE standard has not been fully implemented in all efficiency programs.
Perhaps the reason may be that the science is not supported in practical application?
Certainly there will be a tremendous market for high-tech solutions and the manufacturers and tradesmen enjoy increased revenues.
That is simply not the case in WAP.
There was an interesting study done in Boston on healthy homes. I think you can find it on the NPR website. they made some indoor air improvements, not with WAP protocols, and documented reduced health crisis.
I'm in Florida and have some doubts about some of the 62.2 procedures when it comes to bringing in hot humid air. I don't think there has been much long term reviews off the impact. National protocols don't seem very scientific when they're not climate specific. And I don't think there's much concern for existing funding challenges before adding in another procedure, much less determining where it sits on the list of priorities
Thanks for weighing in Bill,
I am very interested in the Boston Healthy Homes report that you refer to.
I was not successful searching the Boston NPR site (WBUR).
Please share any other link you may have to this information.
While I have no practical experience working in a cooling heavy market like Florida, I agree with your observations.
I have no bone to pick with the work of ASHRAE.
The work that they do is extremely important, absolutely vital to WAP and the home performance industry.
The reluctance of BPI to initiate training was a red flag to me.
The one size fits all approach to new construction, can be reasonably effective, however the retrofit market is another animal.
ASHRAE is obviously aware and has made efforts to adapt, to some extent.
I am perhaps what you would call "old school" in that my approach requires me to have a
plan "A" and a plan "B" in place when I do business.
To address conditions as critical as this with a "Band-Aid" approach due to limited material resources and lack of "best practice information is not acceptable when spending federal funds.
I am sure that USDOE and their affiliate laboratories are working on this, but there seems to be a lag in technology and information share outside of ASHRAE?
Perhaps this type of message board will draw the attention of those most capable of supporting this effort?
I encourage others to share their experience and observations.
The Community Asthma Initiative has served more than a thousand families over the past seven years. It costs about $2,300 per family — not only for staff time, but also for things like plastic bins, a special mattress and pillow covers, and the vacuum cleaner that filters out fine dust.
"For every dollar spent," Elizabeth Woods tells Shots, "you save $1.46 for hospitalizations and emergency room visits." The program's performance was detailed in a report published last year by the journal Pediatrics.
"There's a 56 percent reduction in patients with any emergency room visits," Woods adds, "and an 80 percent reduction in patients with any hospitalizations."
And that doesn't include the savings from lower use of medications, or the cost of time off work for parents caring for a sick child.
This is the type of information that can help drive the funding needed to do the job right the first time.
I will share this with my network immediately.
Hi James and Others in the conversation. I may be biased, because I edit the thing, but Home Energy Magazine has an article by MARTHA BENEWICZ and ROBERT PARHURST, "Ventilation Standards at Work," from 2005 about how Wisconsin WAP handles the 62.2 requirements that you might find very helpful. It's based on experience, not theory. Here's a link:
I am familiar with the work done in Wisconsin.
Unfortunately we have not advanced that much despite those findings.
My suspicion is that as the results of ARRA are being realized, the need to address ventilation is coming to the forefront. Health, Safety and durability are very visible consequences.
I believe that there are many ambitious and passionate weatherization personal poised to address this need.
As the Wisconsin outcome suggests, there is much to be considered beyond the calculations.
I hope that your reference to this excellent document is viewed by many that may not have been paying attention in 2005.