Is there somewhere I can get a checklist for a blower-door test on new construction?
GBA Editor
| Posted in General Questions on
We are building a new home ourselves and are looking for a checklist to help us prepare for the blower door test.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Search and download construction details
Replies
here is one: http://oikos.com/library/airsealing/checklist.html
Strongly suggest conducting a blower door test before insulation. This will allow you to use the blower door and other diagnostic tools such as smoke stick and manometer, to find the remaining leaks. It can be tricky if ceilings are open to ventilated roofs, but a good energy auditor will creatively approach this.
Agree completely with Robert that you need to schedule your first test right before the insulators come in, with at least one exception. If there are vented cathedral ceilings, you need to insulate, drywall, and tape them before the test, or else expect the tester to spend a fair amount of time trying to seal your vent openings. If there is a vented attic, you need to hang and tape the ceiling before the first test, or as above, pay the tester to deal with it.
I think we're quickly approaching a time when drywallers and insulators will recognize the need to perform split installations, and will automatically do the pre-test and after-test work in the right sequence. Or at least I hope we are...
Personally, I have gotten a little jaded on testing completed houses. Those situations always result in me trying to explain to the owner or builder how to fix stuff they could very easily have dealt with before all the finishes were installed. I mean, do you want to pull all the window and door trim off to install canned foam or backer rod because you didn't already install it, or do you want to try to face-caulk all the trim to seal leaks??
Frank,
Did you read this article yet?
Blower Door Basics
Thank for the quick response. Yes I did read the Blower Door Basics but it seemed to address an existing home more. I will look at the link above. This is new in our state as far as enforcement so it has been hard finding someone to talk to who has actually done the test. Unfortunately in my state (Washington state) the price you pay to get someone (few in my county) to do the blower door test varies from $75 per hr. to Thousands of dollars depending on the county; not unusual there are those that want to gouge and the state lends them a hand.
Our law states that you can do the test anytime after rough in and the responses point to doing it just before insulation and I think that is correct. Except you have the roof to contend with the vents, ridge vents solar tubs I just can’t see how you could tighten it all up enough to make this practical. On the other hand trying to find a leak with sheet rock up would be a nightmare. I have seen construction that had a plastic vapor barrier placed over the insulation but before sheet rock on all outside walls and ceiling. Has anyone seen this? Also what is the tolerances like, meaning is the test set to flunk everyone or is it liberal enough that there has to be a glaring problem?
Frank,
Q. "What is the tolerances like, meaning is the test set to flunk everyone or is it liberal enough that there has to be a glaring problem?"
A. It's not a pass-fail test. When a blower-door test is conducted, the technician depressurizes your house to 50 pascals with respect to the outdoor pressure. The technician then reports the result as a number -- often using the units "air changes per hour @ 50 pascals" or ach50.
If the result is 0.6 ach50 or lower, that's very good -- Passivhaus airtightness.
If the result is 7 ach50, that means that your house is about 12 times leakier than a Passivhaus -- but that it still passes the new-construction standard established in the 2009 IRC.
Frank, you should probably expect to pay a few hundred dollars for a blower door test and completion of the necessary paperwork. What county are you in? I'm in Washington also, and can tell you that (a) Washington State University Extension's Energy Program recently gave grants to about 40 recipients statewide to purchase blower door kits, in order to ease access to testing, and that (b) they can tell you over the phone who to contact in your area. If you're in San Juan County, I'll do it or get someone else for you. Anyone trying to charge thousands is way out of reach. It takes perhaps an hour to load in, set up, run the test, pack up, and leave. It takes significantly more time than that once you take into account travel time, finding leaks for unhappy failing owners and builders, follow-up phone calls from those same unhappy folks who want help, billing and getting paid, and so on.
Martin, it is in fact a pass/fail test. We have what is called a "specific leakage area" that is calculated using square footage of floor area and measured CFM50. What's not clear yet is what happens if you fail. It's not a high standard but much new construction isn't quite there.
David,
Thanks for the clarification. I understand what you mean by a pass-fail test, but I was trying to make it clear that the homeowner should get more than the words, "you pass" or "you fail." The blower-door technician should provide at least one number (and the relevant units used) -- ideally several numbers. The numbers should be provided in a written report.
These numbers are much more interesting and useful than the words, "you pass" or "you fail."
http://www.energy.wsu.edu/Documents/Qtr_Sheet_WSEC_2009_Certificate.pdf
Martin, this certificate needs to be posted in (or I believe near) the electrical panel. Note that it has spots to record measured envelope leakage and duct leakage. The inspector will check it at final.
I agree that the tester should leave plenty of written info. I send out a PDF copy of the TecTite detailed report.
David Thanks for your reply your information is useful and if I was in San Juan county I would give you a call but down here in southern Washington thing are not so cut and dry. Our government is besieged by people upset with their polices and this is a good example they are so concerned with the technical details and what constitute the test they completely ignore the people on the ground doing the work or testing. The IRC 2009 standards are in some cases arbitrary and confusing so people just through up the hands in frustration. My recommendations to the state is 1. run the test by a certified technician 2.set up maximum cost for test only. 3.leave a detailed checkoff list for the customer so they or their contractor can isolate the problem areas if it fails. After a maximum dollar amount is spent trying to find and fix the problem. Sign it off. Like with auto emissions test if you show you have spent enough moneys on trying to fix the car’s problem they give you a pass. This is another government Zero sum gain. The cost in money, gas used, time will never pay for the gains you get from this procedure. Like it or not people still open windows.
Thanks Frank for starting an interesting thread. I have two comments:
1) What do the experts on this forum think is the ACH50 number we can realistically shoot for when we try to do a good job on standard construction? The Passive House 0.6 is obviously too low and 2009 IECC's 7.0 seems way too high. Is the 2012 IECC's 3.0 "just right"?
2) Some of you recommend running a blower door prior to insulation, which makes sense as a leak finding tool if you don't expect your insulation contractor to address air infiltration. But Frank needs a test to meet a state infiltration level requirement. Would he not need a second test then, when the fixes have been implemented? It seems to me that the right time to do perform a (first) blower door test will depend on the design of the house and the insulation system that will be used. .
Frank,
You're right that it's possible to build a house without any blower-door testing. But many studies have shown that such houses, on average, are extremely leaky. Investing money now in a blower-door test and air sealing remedies will lower your energy bill for years, and the money will be well spent. You're likely to get a fast return on your investment.
Torsten, my opinion is that 5 ACH50 is quite easy to meet, and that 2-3 is a good goal. One concern I have over the lower targets is that windows become more of a factor. If you don't have particularly good windows you may have too much leakage no matter what you do elsewhere in the house. I have seen a couple of cases like this, where the windows and doors were the weak point. Builders are going to need to be more discriminating in their window choices as the standard gets tougher.
Seems like right now we're in a sort of transitional period as energy code brings blower door testing to the masses. Once you have gone through the process of airtight details once, it's a lot easier the second time, and more and more builders will either own the test equipment or have a sub close by who does, so all of this drama will probably fade away and people will know how to meet the targets without so much hand-wringing.
You are correct that Frank needs a test to pass the inspection. He can either test his shell before drywall and see how it's going, or he can just wait until the end and see what happens. It is quite possible to use a shop fan and a piece of plywood with a hole in it to depressurize the house and find the leaks. You don't have the benefit of getting a leakage number, but you don't have the cost either.
Anyway, Martin's right, all of this is money well spent and there will be a payoff.
My wife and I have decided not to apply for a building permit at this time thank you all for your input but because of the uncertainties of the law and our inability budget for the cost we just can not go forward. From what we can gather the cost for the blower door test is between 150 and 500 per test but there is no limit to how many times we will have to have the test to comply 1, 2, 5 no one can say. Then there are cost for foam caulk tape to seal and labor to seal every crack according to the state of Washington’s new energy code 502.4. plus the upgrade of all doors and windows the uncertainties of cost is just to great. The project is scary enough with out the thought of spending weeks and thousands of dollars on test after test its all to much. This to me signals the end to the owner / builder because of the inability to budget for ramifications of unforeseen number of tests.
Frank,
Like you, I am an owner/builder. To build a house, you either have to learn certain skills -- mixing concrete, rough carpentry, roofing, and air sealing -- or you have to hire a contractor who has those skills. And yes, you have to budget for all of these things.
If your budget isn't quite large enough for a home-building project, that's perfectly understandable. But the problem isn't the blower-door test. After all, the blower-door test is designed to help you lower costs, because the test will result in an energy-efficient building that will save you money for years.
Perhaps you can design and build a smaller, more affordable house. If you do, be sure to build it tight! You'll be glad you did.
Frank, you're making it sound a lot harder than it is... "spending weeks and thousands of dollars on test after test?"
All you need to do is plan your air sealing details before you start, and then execute them as you build. Yes you need some added material, but not a lot. At most you need two tests at a few hundred dollars each.
I posted an answer but it was it censored out (didnt make the cut, apparently) because I spoke clearly and rationally about what was going on in Washington?
Bill,
I'm not sure what you're talking about. As far as I know, I never censored any comment on this thread -- although I'm not the only editor at GBA, so it's possible that someone else did.
We have no objections to GBA readers posting political opinions or criticisms of Washington on this site. Very rarely, we find it necessary to remove posts that use vulgar or inappropriate language. We also ask those who post comments not to insult other GBA readers. It's fine to attack their ideas, but not to call them insulting names.
Assuming you abide by these simple rules, there shouldn't be any reason why your strong political views can't be shared.
Frank,
I'm a contractor in NH who has done LEED homes and I understand your situation. Owner builder is not dead. What I have done for some customers in your position is develop a budget and game plan,and I'm sure you can find a contractor willing to that. He will also have a relationship with local inspectors so he'll know what to look for. It is a maze for professionals, so don't get discouraged, the time and money spend in this manner will save big $$$$ down the road.
Frank if your still out there...
It's a shame that you have chosen not to build based on your worries of reaching Washington State air leakage requirements.
Reaching the 5 ACH 50 (or the equivalent 0.0003 SLA) is not hard at all. It's really not even much of a code improvement in terms of actual performance. Most new construction projects currently test around 7 ACH 50 without improvements in air sealing details. Meaning... If your project is like the average, it would reach near this level without extra work. Bringing the typical project down to below 5 requires far less skill than than you would need to frame a house. After all... Your only plugging up holes. It's really not that tough.
It reads like your worried about trying to fix something that you can't see (leaking air) when it too late to reach "it" because it's inside the construction... and your finishes are up... and now you're at the mercy of a blower door guy... who you don't trust... and dealing with a regulation that is new and that no one understands... and this blower door test and it's $75/hr rate could go on forever because you can't even see what your trying to fix because the frigging leaking air is invisible!
It's not like that. It's very doable for any skill level or project budget.
The improvement to to the Washington State Energy Code is not the new 0.0003 SLA requirement. The code improvement is that... there is now a requirement to meet. As air sealing methods become better understood, then well see actual performance improvement.
If you change your mind about your project, I'll invite you to our air sealing workshop for builders next month. It's in Portland (right near where you live in SW Washington) and its It's free. The info is at http://www.smallplanetworkshop.com
I just did my first energy code blower door test for a builder this past week. Small, one story, stick-framed house on a raised floor. He had made himself aware of what the test was and how to detail everything. SLA=.00013, CFM50=225, he could have been around 600 and still passed. I was able to run the test on the C ring but now wonder if I should buy the D, for the next time he calls me. I need to round up some good printed material on mechanical ventilation that I can give to people so they can determine if they have it covered.
Dear Frank,
Call me at 505-983-5125 and I will discuss with you our company's approach to helping owner builders go through the Green Building Code here in Santa Fe, NM. We offer, at a fixed price, to be the builder's quality assurance manager dealing with green building issues and our city planning department during the building process. For a house under 3000 SF we must deliver HERS 70 and meet a points count. We provide certification and input to obtaining the occupancy permit. We won't get a final payment until the house has that permit. So, as you can see we are active from the planning stage through the construction phases. We must do a final blower door test, and may do others if there are leakage issues when something can be done about it.
Steve Bradley
[email protected]
Thanks you all for your comments please keep them coming. What I am noticing is the people that have a vested interest in doing the door test are all for it and the ones that have to pay for it are dubious. I also notice that even though I have never said how big of a house I am building that every one seems to think I should build a smaller house. I think this is the actual agenda smaller and tighter. Even saving 50 dollars a month I will be dead and gone before its breaks even. I am still considering the project but until I hear from someone in “my shoes” I will still think this is an open ended problem. Has any home owner built and gone through the test?
Dear Frank,
For a good discussion of the blower door thing, check out http://www.buildingscience.com/documents/insights/bsi-053-just-right-and-airtight/
Bill D.
That's an asinine comment and makes me regret spending any time trying to help you. I'm a general contractor who primarily uses a blower door and other diagnostic tools on building projects for my own customers. Increasingly, other folks who are building call me for consulting or other help, including blower door tests, but that hardly constitutes a "vested interest" in doing blower door tests. Many times those calls are distractions from what I really ought to be doing on my own jobs.
This is a perfect example of the shortsightedness that plagues the building industry in this country. You're thinking in terms of a few years of your own occupancy, when the house might be there 50-100 years or more, and poor energy decisions you make now will be hurting future owners who are trying to pay increasingly costly utility bills. Good decisions you make now will return the cost many times over during the lifetime of the house. Yes, you have to look a bit past your own wallet to see this.
I've done many, many residential energy inspections for the local utility, and gone to house after house where poor choices were made in the original build, in some cases leaving unsuspecting later owners with remodel/repair situations that will cost a fortune if the house is to be made affordable in terms of heating cost. We have an owner/builder exemption here that has helped that phenomenon, in my opinion, by allowing folks to skip several inspections that would normally be required.
Anyway, what you ought to do now is build as cheaply and poorly as possible. That way, someone like myself will get two jobs in the future. The first will be when you try to sell, and we come in as a consultant to provide an energy assessment to your prospective buyer (this is an increasingly common part of what buyers want to investigate). They can use our report to knock down your price. Then, we'll get a nice remodel project in which we remedy all the problems. By all means, skip the blower door test and whatever else might help you build a durable, efficient house.
David... That's why I waited a day to comment...
Frank... If we wanted to make money on unsuspecting home owners or owner builders, I can assure you that it would not be through green building, or air-tighness. I can do much better in other industries. No question.
What rankles for some, is that many are here because they love thke idea of helping people like yourself learn and understand ways to build good homes that while comfortable, use considerably less energy.
It's not that we want to save you money by using less energy... It's that some of the people here really believe that through better buildings that use less energy, our offspring and their offspring will have a better opportunity at having a planet that will resemble the one that we have today.
If you can imagine that our interest in air tighness, and the increase in code requirements, comes from a desire to help future generations and not from the desire to get a few meager dollars out of your project, then you can imagine that suggesting that the people involved are motivated by profit over people would not be well received.
Even in my small town, there are two guys who have jobs that support them and their families, who have started an energy asssment company and do blower door tests. They have done this at great personal risk and investment, simply because they want to spend their working hours helping people live better. I like people like that. Those are the type of people that also contribute here at GBA.
Keep in mind... A house built to code is simply the poorest house that you are legally allowed to build...
Best of luck on your project.