How Much Extra Will the HVAC Cost for ENERGY STAR Version 3 Homes?
I just finished teaching another ENERGY STAR Version 3 class for HERS raters. As usual, the new HVAC requirements generated the most discussion and raised the most concerns. I haven’t heard any hard numbers yet, but I’m wondering how much additional cost the new requirements will add to the HVAC contractor’s invoice.
I just finished teaching another ENERGY STAR Version 3 class for HERS raters. As usual, the new HVAC requirements generated the most discussion and raised the most concerns. I haven’t heard any hard numbers yet, but I’m wondering how much additional cost the new requirements will add to the HVAC contractor’s invoice.
The two new requirements likely to have the most impact on cost are:
- Ventilation system designed to meet ASHRAE 62.2-2010
- Air flow test and balance
A supply-only ventilation system using an electronic damper with a controller, such as the AirCycler or Aprilaire ventilation control systems, is generally the least expensive, running about $300, I believe. Using a heat recovery ventilator (HRV) or energy (enthalpy) recovery ventilator (ERV) usually costs more, although Panasonic makes a small ERV that costs about $300 before installation. Standard ERV and HRV models can cost $2000 or more.
I don’t really know the cost of negative pressure ventilation systems that use the exhaust fans in the house because they’re not a good idea down here in the humid Southeast, but my guess is they probably also run in the hundreds of dollars. It’s basically going to be the cost of a controller and installation since the fans are already there.
The new air flow requirements, I believe, are likely to add significant cost to the HVAC system in an ENERGY STAR Version 3 home. I think it’s a great idea and have advocated for more focus on air flow here in the Energy Vanguard blog. The truth is, though, that even in ENERGY STAR Version 2 homes, most HVAC contractors don’t measure the air flow characteristics and ensure that the duct system is doing its job.
So, to all our readers who are in the HVAC business, how much extra will it cost for you to meet the new requirements in the ENERGY STAR Version 3 new homes program? Also, to our home builder readers, are you finding ways to offset the extra costs with savings, either in HVAC (reduced system size?) or other areas, such as advanced framing?
I think the biggest opportunity we have here with the ENERGY STAR V3 guidelines is to find different ways of doing things that accomplish the same objectives but do so in more elegant and inexpensive ways than just adding on all these new requirements to the standard methods. What do you think?
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I am having a real hard time
I am having a real hard time finding anyone who’s even certified in our state of Connecticut. I am ready for HVAC on the new house and the whole project is delayed because I cannot find anyone who’s qualified.
Does the V3 guideline require
Does the V3 guideline require that the damper on a supply side ventilation system be a motorized mechanical damper?
I have had some discussions with the Florida Solar Energy Center about affordable housing whereby they might recommend a manual damper on a dedicated fresh air duct to the return plenum that is easily accessible to the homeowner. Granted this allows air flow into the house at all times (the damper can be adjusted and the air must be filtered ) it does away with the cost and potential (and unknown?)failure of the motorized damper.
What about meeting ASHRAE 62.2 by identifying an exhaust side system? Here, so long as a (bath) exhaust fan meets the flow, noise and Estar requirements, that fan could be identified by builder and Rater as the ventilation requirement, no?
Without getting into the whole- house pressure issues and preferences, the above (exhaust) ventilation system would do away with the cost of the air cycler and motorized damper.
Many Raters are working with Habitat and may be facing these cost issues.
Perhaps a real cost to many builders will be dealing with getting their HVAC subs to become certified Energy Star contractors. It is easy to say to just find another contractor that wants to participate in the program but the reality is that outside of larger metro areas, there is not always a certified HVAC contractor to go to or that you might want to work with.
It seems that more than a few builders will be forced to either absorb or help with the cost of getting their HVAC sub certified.
I agree with Peter. Here in
I agree with Peter. Here in Chicago your hard pressed to find an hvac guy who even knows how to do a manual J or D. It will be a struggle to change the hearts and minds of those in the industry towards energy eficiency.
Peter F.:
Peter F.: Finding HVAC contractors who have completed the training requirements is another important issue new to ES V3. I believe that you should be OK now since you won’t be qualifying your home for version 3 unless it’s not finished till 7/1/12 or later. See the ENERGY STAR V3 transition timeline to determine which version the house qualifies under. I can’t find a definitive answer on the website, but I believe that HVAC contractors can complete the work on V2.5 homes without the new V3 training. Contact the folks at ENERGY STAR to find out for sure: energystarhomes@energystar.gov. They’re very responsive and will get you an answer quickly.
There is no global it will
There is no global it will cost X, as some builders / trades have already incorporated or do some or all of these items already, while others haven’t.
As for inexpensive means, sorry but that is a misnomer – lets say it costs $500 or $5000 more up front – how much is saved or gained in living in a better performing / healthy / comfortable home? How much more does it cost a builder / trades / homeowner to come back and fix an issue later?
The big fight with HVAC
The big fight with HVAC contractors is they have been doing things the same way for 50 years and change will be difficult. It’s on the job training from people who have been doing it for years that gets handed down from generation to generation. The typical install consists of grossly oversizing equipment and not worrying about duct systems. A 100,000 BTU furnace is only $100 more than a 45,000 BTU model, it’s cheaper than fixing the duct system. Same on the A/C side but giant equipment has a harder time getting that cooling through undersized ductwork.
Getting the air distribution right (and therefore temperatures even room to room) requires proper ductwork design (manual D & J) or lots of trial and error. Both require a lot of time which few contractors are willing to do when they are trying to drive bids down in order to get the low paying new construction jobs.
Based on several years of
Based on several years of experience working with better than ESv3 specs and using a base-line of 400sf/ton and bad systems, I’ve found that my clients save money on well designed, installed, balanced and commissioned systems. It’s a no brainer.
Ideally it should not cost
Ideally it should not cost any more to do it this way, which is to say to do it right. I think this is where we are headed eventually. I have been through the learning curve and I can almost do the work for less now, if I can design and install the HVAC system from scratch.
Some of the things needed, that are different from where we are and where we are going are so simple – it is hard to understand why HVAC guys do not change what they do even just a little. It only take a little here and there.
Actually I think the real problem is that HVAC guys and contractors have no good method to go from where they are to where they need to be. There are not a lot of courses readily available – and a lot of the problem is that the training that is available comes from the manufacturers who mostly have no ambition to support this kind of work.
I say on the surface the cost is probably $300-700 more per house. After a year or two that additional cost will drop off and prices will equalize.
In NY the most common
In NY the most common technique is an energy start labeled bath fan with a timer in parallel to the light switch.
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My preferred option is Panasonic fan and a Grasslin timer.
-Rob
For our projects with smaller
For our projects with smaller budgets (e.g. no ERV – the right way to do it, but pricey), like Habitat might do, is bath fan on electronic timer. Lutron or Intermatic.
For replacement air (our homes are routinely 2 ACH50 or less) we cannot effectively move enough air, and at the very least do it without creating condensation opportunities in the envelope (we’re in mixed/humid Maryland). We use a 4-6″ duct for supply air cut through the band joist or soffit. The fresh air is introduced into the return air trunk. The damper is passive, by Tamarack Technologies – no electronics, no wiring, no breaking parts. $15 get’s it done.
In the end, we have a bath fan coming on creating negative pressure. The Tamarack damper opens up and lets fresh air into the air handler or furnace return, which then gets filtered. The clean make-up air then moves through all of the registers on the supply side, moving ever so slowly to the exhaust fan in the furthest bathroom.
My ONLY concern is that the negative pressure in the return air duct will draw cold or hot air when it’s not called for by the bath exhaust fan. BUT, since the house is so tight, even if the furnace/AH constantly drew fresh air, it would be fighting against positive pressure created by the tight envelope to get out!
@Harris – that sounds like a
@Harris – that sounds like a good solution. I like the durability of no additional motorized parts added.
From what I have heard on the testing of passive fresh air inlets to return plenums, is that they do not move nearly as much air as thought, when they are tested with a flow hood, while the system is running.
The exhaust air fan to ensure it is doing the job is a good one.
So, assuming your climate is very humid, is this giving results on actual installs there?
@Christopher – like most
@Christopher – like most everything else in green building, it’s too soon to tell. Wish we had the benefit of NAHB’s research center equipment set up in all the custom homes we’ve done over the past years. However, owners are not complaining, and we’re not getting call backs. Never complaints about humidity or dryness – no headaches from poor IAQ.
We’re using 6″D supply ducts even when we need only, say, 92CFMs. As long as we don’t get stupid (lots of flex, to many turns) on air flow, I can’t see how you’re having problems moving enough air through a supply. This has to be related to the amount of negative pressure in the building, I would think.
In the KC area there are only
In the KC area there are only two HVAC contractors “credentialed” to do E* V3. Most of the builders (including one habitat group)are leaving the program. As other bloggers have indicated there is more than one way to meet ventilation requirements. However, the additional air requires conditioning and it does impact the heating and cooling loads of the home and must be considered in the sizing of equipment. Inexpensive attempts at ventilation are just that. The ventilation strategy must provide for controlled and conditioned air.
The fresh air intake has
The fresh air intake has always come up with me when the house tests too tight , but I cant shoot from the hip and have to revert to saying ” Its up to the mechanical engineer ” . Now on the test and balancing I have been doing that for almost 10 years now so it comes second nature .I also think the key is testing the statics of a system(though they aren’t always what I expect). Manufactures need to install ports on their system and they should be included in the supply/return plenums. If you think an 8 inch duct delivers 200 cfm all day , think again . Ive noticed maybe 1 out of 1000 ! Gotta go , wife is wanting to go online shopping but I am very interested in the feedback that comes from Energy Vanguards blogs and posts , keep up the knowledge Mr. Bailes…
Energy Star did a study on
Energy Star did a study on the additional costs of v3 (http://1.usa.gov/3SXyYa). For HVAC, here’s what they came up with:
Contractor checklist: $400
Rater checklist: $50
IAQ/Ventilation: $500
Cost of V3 is different based
Cost of V3 is different based on spec of house that you starting from. As far as paperwork and tech time you are looking at 600 to 800. Thats in DC metro area.
I think our cable operated
I think our cable operated balancing damper offers value to contractors trying to satisfy ESv3. Damper is mounted at the trunk with cable routed inside the ductwork and terminated right behind the register. Any noise is attenuated and Balancing tech can adjust through the face of the register/grille. D R Horton is putting in model homes to tryout. See http://metairtech.com/products-manual-damper-systems.aspx Feedback is appreciated…Mike
I have been doing test and
I have been doing test and ballance HVAC for 15 years with in 10% each run, useing ACCA MJ8 & MD & MS. Its still more the buiding than the HVAC. I have a “energy star” V3 house that still is not sealed and I can not heat it in high wind. The duct work is sized at .05 SP and is 30% larger than most “3 ton” or my teck says I put in 5 ton duct in a 3 ton system and duct all return and seal with UL listed 181 mastic. I have 2.7 times more time and 2X mat. Up charge was $4500 for duct. sealing and 1.5″foam was done by foam wall installer his charge was $1500, plus $600 to do the Mj&D; or .25 sf
Harris – I have been working
Harris – I have been working with Advanced Energy in NC for over 10 years working on System Vision Homes which are super efficient Habitat Homes that use the positive ventilation approach like you mentioned. However – they used a fixed damper. In your comment you said the bath fan creates a negative pressure and the tamarack damper opens. Is this because the house is so tight that your bath fan can depressurize the home? If so what prevents the Dryer (200-300 cfm) from pulling from this vent, or the kitchen exhaust. Do you pressure balance the homes to make sure that when operating the home doesn’t go under negative pressure due to supply duct leaks outside the envelope. Just curious. We used to use Air Cycler’s but they began creating comfort complaints from operation during the shoulder months.
For new home construction,
For new home construction, continued achievement of ENERGY STAR certification under version 3.0 (or version 2.5 for homes permitted in 2011 and completed by June 30, 2012) will qualify homes for HFHM resources. Affiliates unable to partner with a credentialed HVAC contractor should complete and verify all work and checklists required for ENERGY STAR 3.0 certification except for the sections of the HVAC checklists that cannot be completed for lack of a credentialed contractor. Upon final verification, the house will be accepted as though it were certified to version 2.5 of the ENERGY STAR program.
All Home Energy Rater
All Home Energy Rater partners are required to take ENERGY STAR for Homes Version 3 training and pass the national ENERGY STAR exam through a RESNET-accredited Training Provider by January 1, 2012, to be eligible to qualify homes under the new guidelines. This requirement applies to all existing ENERGY STAR rater partners, as well as any new raters who sign onto the program in the future, and includes field inspectors who are doing inspection and testing associated with ENERGY STAR qualified homes.
All Home Energy Rater
All Home Energy Rater partners are required to take ENERGY STAR for Homes Version 3 training and pass the national ENERGY STAR exam through a RESNET-accredited Training Provider by January 1, 2012, to be eligible to qualify homes under the new guidelines. This requirement applies to all existing ENERGY STAR rater partners, as well as any new raters who sign onto the program in the future, and includes field inspectors who are doing inspection and testing associated with ENERGY STAR qualified homes.
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