Blower Door.

Mark Hunt

A BD test can and often does require a few hours to complete. I've done hundreds of them and when you are trying to identify specific areas for air sealing issues you can expect to be there a while.

If all you are doing is calculating an infiltration number for a heat loss, the time is shorter.

Just a reminder to anyone doing these tests:

Remember to turn off all combustion appliances first.

If there is a fireplace in the house and it has ashes in it....CLEAN IT FIRST!!!!

If there is a fire in it..........go home!

I did a test in a home once and when I fired up the blower, balls of cat hair came flowing down the stairs from the bedroom upstairs! My BD found the spots mom missed with the vacuum!

On another job, the house immediately was filled with a foul smell. The plumber never put the vent stack through the roof and we were pulling sewer gas back into the home. P U!!!!!!

Mark H



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jwade55_3

Does anyone incorporate a blower door as part of their daily business plan? And if so, what is the ROI look like?

J

Al Letellier_9

HUH???

> Does anyone incorporate a blower door as part of

> their daily business plan? And if so, what is

> the ROI look like?

>

> J





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Al Letellier_9

HUH???

Excuse me for being French ( I really am ) but what are you talking about???

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Empire_2

Double Huh???

Please explain what you mean....

Mark Hunt

I think


he is asking whether or not anyone does blower door testing when they go out on sales calls for equipment replacements?

It would help your heat load calcs by determining the actual ACH.

Mark H



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Brad White_6

I use one sporadically

in doing energy audit work. I do not own it but have access to it occasionally. It is a Minneapolis Blower Door if I recall. Another is by Infiltec

http://www.infiltec.com/inf-bd.htm


What is being referred to is an expandable panel that fits into a door opening. The panel has a fan attached to it, a manometer and a fixed orifice. Essentially you close all known doors and windows, fireplace dampers, etc. and pressurize or de-pressurize the house and measure the leakage of the house envelope at a given pressure (usually 50 pascals, don't ask...). The figure given in common terms is ACH-50 or air changes per hour at 50 pascals.

(Sort of like expressing velocity in "furlongs per fortnight" I would suppose. )

Anyway, I use it to test improvements in a home's envelope both before and after weatherization. Usually this means caulking but obvious things like fireplace dampers show up immediately when you cannot get a differential pressure..

As for a heating pro? It might set you apart from your competition. Speaking as an engineer, I know it takes the variable of infiltration out of the equation and nails it down as a common number. We all know that absent definitive data, infiltration either by the crack or volume or "per SF" method is really just an educated S.W.A.G., right?

Blower doors can be pricey (several thousand I understand) but imagine you could make one with a fan and Dwyer electronic manometer. Will it ever pay back? No idea... You may have to do a lot of testing as an additional service to read a positive cash-flow. Otherwise I would think it is in the "feel good" catagory that a homeowner is getting a more accurately calculated system. Not sure if they would pay for the privledge but a savvy homeowner might. So you would have to market the concept as part of your services I would think. Educate a homeowner and make them a believer. Give them an ACH-50 number they can brag about!

Would love to hear how you decide to go.

Best,
Brad

Douglas Hicks

Such a door is also used in testing for air infiltration prior to the installation of gaseous (halon, Intergen)fire suppression systems. If the area leaks too much,more expensive fire suppression chemical is needed.

fireguy

jwade55_4

Mark is right.

I am starting a partnership with a great installation guy, goal, to provide the top level HVAC systems in our market area. One idea I've had is the blower door, as an adjunct to our business. Provide blower door testing for retrofits, as well as to builders for new homes they are outsourcing the insulating on.

Looking for feedback, we are on the verge of ordering one, from infiltech.

J

Brad White_6

Excellent

application, Fireguy. Makes perfect sense. And another market too!

hr

pretty time consuming

to do a blower door setup on all sales calls.

We tried this at a HVAC company I worked for briefly. Hard to keep the customers attention through the process also

hot rod

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Brad White_6

Good strategy

if you market the blower door and set yourself apart from the competition. Sounds like the volume of business will take care of it self. My guess is that if you do not do it someone else will. So you might as well set the standard. You can amortize the cost over the many jobs you are sure to have. Even if you break even you and the customers win.

Another thought: if a warranty fix it could settle the root of a house that is too cold, or eliminate the infiltration variable.

Brad White_6

Only takes about

a half hour to set up and about another half hour to do the test. Unless the HO is an engineer. I hear it takes a lot longer then

jwade55_4

HR,

Not really thinking about every sales call, but intersting idea? Just considering using it as a sales tool, offering to take energy monsters, and tame them a bit, as well as upgrading their mechanicals. Trying to figure out the market for this, as well as how to charge.

J

jwade55_4

Brad,

Sounds just like the FAQ on one of their websites, great quote though!

J

Joel_3

Got one!

we have a blower door and are members of Comfort Institute. I have yet to use it on every sales call , I don't have time and niether do alot of the customers . mine is by Retrotec . I do not believe that it should be done as part of a "free" sales call. I offer the testing on a call and generally come back to do it but charge for it . it is true though that you really can't do aheat loss without it and be acurate . I tested two houses same type,size,year. One was 7ach per day the other wasd 23ach per day. if you don't test your just guessing st the heat loss.

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Tom_35

Have one too

We have the Retrotec and sorry to say, but it sits and gathers dust 99.9% of the time, and basically it's our fault. We could not make it work financially and our sales guys finally quit using it.

People weren't exicted about bringing in hot air during the summer or cold air in the winter to test the house. Then after the reports were delivered, they were hesitant to make the needed changes. We are HVAC contractors, not carpenters, window replacement and threshold people, not fireplace damper repair people, etc---and it's hard to find contractors that want to do these small repairs. Plus, the customer just didn't see the value in the test.

As far as builders wanting the test after they have built a new home---forget it. They don't want to know they have screwed up, the just want to finish it, sell it, and hope they don't have to do much for the first year the homeowner has the home. If you do the test, more than likely you will expose problems, which is something they don't want.

Tom Atchley

Brad White_6

Actually

it is an old chestnut in the public domain and applies to ANY technical endeavor performed in the presence of an engineer.
Just cannot help ourselves!

jwade55_3

Being an engineer, I agree I just find in funny that someone actually put it in writing. You should have seen the look on the face of the Direct TV installer that did my dish the other week, something like "where did they find you?"

J

Weezbo

In the 70's i considered making one

and dragging it around to the leaky old homes and proving the infiltration was way over the top to people,also considered installing hrv's a long time back,used to do a considerable amount of forced air,lucky for me i generated enough interest in the wacko ideas that now there are more inspection done in our area.The homes that are built new have been influenced over the years by professionalism and to some extent by people generally concerned with their health.

oops...The thing is while it would be easier for you to run around providing the blower door test as part of your service you would likely have to look to the various certifications and requirements to maintain them,which brings on a great reason to be an inspector for a Bank *~/:) not saying the King snivelers wont misconstrue everything one day to the point you cant belive your own eyes and ears in their own humble opinion.

I would say at least you wouldnt have to look around to find an independent Blower Door Tester :)many Sheet metal shops see HRV's and Erv's an asset to their bottom line when one of the boiler salesmen (which i may happen to resemble from time to time ) suggests a hydronic radiant system.so, if you have a friend who you are sure likes sheetmetal and pounding in hrvs with you on your jobs it would be worth it to you. then you would Know the level of installation,you would know the system is balanced perfectly,and if you are hooked up with a general that does quality work on the insulation and vapor barrier side and weater barrier who happens to understand the value in new innovative window glazing and the like......could turn out to be the best investment you ever made. Just dont Give it away.

i am fortunate in that i put alot of other tools down over the years and encouraged others to pick them up.

i dont have to install the line sets or coils or duct work or L-vent roof packages,ervs hrvs preheat coils and since about may of this year i have seriously considered bagging off the Drain waste and vents and potable water in favor of just doing Boiler and hydronic heating and the controls for all these pieces... Hot Rod made a real good point this summer, when i found myself deep in the apple barrel wondering how in the heck can i get all these houses finished zooming all about the country side fried to the NTH degree....and the idea of installing hrvs and doing blower door tests sometimes enters my thoughts to this day when i have to wait or when i look at some of the work and know that there certainly cleaner ways to install these parts and pieces straighter .the reason i know is because i have done the work and when i rough in the Drain waste and vents i do my best to make that way certain and clear .

when you are doing all the work on a job then you can get things done with some slightly better consideration for The Work because you know how it is.....only problem with a "closed school" is that it could shut out "influences" that are worthwhile. Why not consider hiring some one Else who already is doing that work and will listen to your thoughts and give you their best.First.attend the same classes with them when you upgrade your mechanical liscence. its 3 a.m. and i woke up at 12 33 to go finish a boiler. so i may have to bomb out of here for a couple ten hours or so.

hr

The exact same issue came up with IR cameras

A local utility bought a camera years ago with federal funds. The plan was to photograph roofs and house walls in the community as a freebie to show homeowners where there energy was going.

Camera did a fine job, homeowners said thanks and nothing else happened!

I suspect with todays high fuel prices that might change a small bit. Still the majority just don't go to the expense to upgrade the building envelope.

Too bad this is where such a large portion of the energy savings could be harvested.

It would be nice to come up with a plan to IR and blower door homes if it could at least pay it's way

Maybe fuel prices have to double again before the general public gets the wake up call?

hot rod

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GW

No wonder why people aren't spending money


Wow, after reading some of the posts, I think I'll bring my blower door down to the local Salvation Army.

Here is one small thing that has changed in the last few years, especially this year: the heating costs are all over the news; it's almost a daily thing. As soon as some heating guy or energy guy figures out a way to crack the code with a good marketing message, it might start a revolution. A builder paying for a blower door test? HA! that's a joke. How about a home owner that just shelled out a half mil on their dream house, and they're unhappy with the "low bidder" heating system? I think they might pay. I dream of the day when having a high performance home/heating system will be fashionable.

Heating guys (like me) aren't known to be marketing geniuses; the opposite is true. We tend to NOT expect payment for our intellectual skills. I can only imagine I'm ruffling some feathers here; no one likes to think they're a hum drum cog on the wheel in the world of commerce.

I'm looking into an IR camera. I want to offer the complete package. Without blower doors you don't know the infiltration, without IR you can't see the crappy insulation and air barrier. Even those of us who do heat loss on every job are guessing at two major factors, insulation and infiltration.

That's another thing I learned from the Comfort Institute people, too many people think insulation magically stops air movement, insulation simply slows down thermal energy transfer. Think about this, how good is a radiant system with a stream flowing beneath the slab? Stupid question I know! What about air moving through a house, even though it's well insulated? Same thing!

This stuff is above the average heating and cooling guy. Only those that truly want to rise above the norm will pay the costs for the tools and training.




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hr

Lump in CO testing

for an even more complete "Home Comfort Testing" company.

Blower door, IR camera, and CO checks at all appliances. When you think about it they all relate.

I know a blower door can be installed and fired in an hour or less, but going around with the smoke pencil and locating and pointing out leaks can take additional time.

hot rod

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GW

1 hour to set up blower door?

I can have mine going in 10 minutes, I'm not kidding. Now, it takes an extra few minutes to make sure the house is safe to run it (make sure atmospheric appliances don't fire, make sure there's no fire in the fire place, make sure you don't suck out the ashes from the fire place).

gary

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D107

ho just had blower test

and it will take me at least MONTHS to get around to doing all the sealing then insulating I'll have to do--regardless of the heating prices. Found at least 30 places of infiltration--should have marked them with pieces of blue tape instead of just writing notes down so I can find them easily again.

The suggestion was made to work together with someone who tests and then seals/insulates--that would allow you to do what you do best: install heating systems. When marketing newer efficient boilers, customers will want to hear the savings given their current condition; then based on knowledge of the house you can predict another x% savings by stopping ex- and infiltration.

But of course with a tight house you may have to consider ventilation and fresh air intakes. So now you're the bad guy whose price has to be higher since you want to do the job right. Consumer consciousness will be raised on this over time...

There are so many variables even in 'simple' boiler installation. Does my system need to be re-piped beyond mere near-boiler piping due to prior improper sizing, routing, etc?

I think if you offer a reference to an insulating contractor as an option (with a commission to you if he gets the job) to interested customers it might work for you. Otherwise I don't know how you can stay on top of your primary trade with all the developments flying around.

David

hr

A re-test

would be a nice selling touch for the B-door contractors.

The before and after results would be helpful for the HO, and help with any equipment replacement calcs.

hot rod

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Joel_3

re-test

we just cahnged out all the ducts on avery leaky system that was 4 yold. We will retest all the ducts after we are done to show the results

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Mike Thomas_2

Straight Story on Blower Doors

1. No you can't make one with a fan and a pressure gauge. the fan has to be calibrated to measure how much air is passing through the fan, and the pressure on the house.

2. No you can't do one in 10 minutes, or 30 minutes. You have to calculate the volume of the house, and surface area, prepare the house, and then test, then go back and then put the house back in order. An easy, simple house is 1 hour, and can take 4 or 5 hours, if it is a cathedral ceiling with a gazillion dormers. You should also take time to explain what you are going to do to the customers house, and then what the results are.

3. Minneapolis Blower Door leads the pack on this deal. Most of the other brands are a knock off. And like most knock offs, you might not get everything you paid for.

4. Yes, there is training involved. It takes a very good understanding of building science, building construction, materials and methods. And like everything else you do, experience goes a really long way. Just cause a guys got the tools, doesen't mean he knows how to use them.

5. We get $300 plus travel for a blower door test. If they want a re-test $100-$150 plus travel.

6. Our customers are almost always guys like you, heating and cooling folks. We are called in because the house won't heat or cool properly. The people we work with are very professional. They do the heat loss calculations or cooling load figures and install good equipment. It is always the house construction.

7. It works out that I am the "Independent Evaluator". The referee between the heating contractor and the general contractor and the home owner. I come in and do the test and explain the results. I don't take sides. As a heating contractor, if you tried to the the test yourself, it would not have as much credibility as bringing me in to do an independent evaluation.

8. Bottom line: Design the heating/cooling system with a specific or at least narrow range of acceptable infiltration rate and include that in your calculations and your proposal. When things go sour, like the house I tested last week that had 18 air changes per hour and couldn't get the temperature above 42 degrees, you point out that 4 or 5 air changes is much more acceptable and what you designed the system to handle, the customer will immediately turn to their general contractor, and your off the hook.....

Christian Egli_2

You kick my tire and I'll kick you

I am all for measuring everything, it's the only way to go if you want to know what you're doing. Buy the gadget, rent it, borrow it, find one used.

As a marketing tool meant to please and rope in the customer, I'm not sure, I don't like any concept that shows data about the home that is unflattering for the customer. Marketing should be the opposite: show picture renditions of the new boiler... all color coordinated... all in pink...all value oriented... all positive.

For instance I don't like it when an insurance agent tries to scare me into more coverage. I don't like it when a doctor performs a medical test to show me scary numbers. It may all be for my own good but if I suspect I am being subjected to some scare tactic, I'll run away. Fast.

You tell the customer: "Yep, sir, you've got leaks all over. Your home leaks so bad it's like a leaky sieve, not even a good one." I'd be insulted right off the bet.

I don't particularly see the value of the special test on a first sales visit. It should be done only once the home owners have realized for themselves there is a problem that needs further investigation and fixing.

Sell the solution, not the test.

Only an engineer will fall in love with you just for measuring his thing.

Bob W._3

Fairly well stated. Was that 18 ach at 50 pascals? Wow.

Mike Thomas_2

That was Calculated

I had a wide open fan and could only get it to 15 pascals. It was leaking so bad! The computer calcuated 18 at 50 pascals. The equivalent leakage area, if you combined all the leaks in one spot, was a hole 2 feet wide and 4 feet tall. When I explained that to the home owners, they immediately turned from the heating/cooling guy, who they thought they were mad at, and jumped the general contractor. The wife's words, "I didn't pay for no f---- barn!"

Tom_35

Infiltration, leaking ductwork, and smoke puffers

From what I've read on this site for the last couple of years, the northeast area of the U.S. doesn't see near as much forced air systems as we do in the South, so I'm thinking that the infiltration issues would not be as great as what we see. 99.9% of the systems installed inn our area are some sort of forced air (gas, propane, heat pumps), and there are very few radaint heating systems. Steam is unheard of with the exception of large commercial or institutional buildings.

We see ductwork leakage, especially on the return duct, in EVERY system we look at, regardless of age. Our company is known as the highest price company in town, and that's fine. We can't compete with the guys that buy something for $1000, sell it for $1100, and think they've made $100. While we have blower door, we struggled with making it a workable solution. We now incorporate methods from National Comfort Institute in checking and repairing duct systems. Use of tested methods to determine actual efficiencies of the total system works well, and we are the only company that is doing it here.

We have kicked it around about upgrading our blower door to the new software from Comfort Institute (different company than NCI), but due to the issues we had with customers seeing the value, we are struggling to decide if this is the direction to go. The blower door is going to point out the envelope issues, as well as ductwork issues if the duct is included in the test. The real problem comes with getting other contractors to do the repair work on the envelope of the home.

Smoke puffers really work well in showing the customer where leaks are around the home, and the customer can see and understand this without a lot of problem. Most customers don't understand paschals, and really don't care to do so. Show them the smoke movement and they follow that. Smoke puffers also are great for following crazy air currents through the ductwork when the fan is off.

Tom Atchley

Larry Weingarten

Small steps

Hello: There is another diagnostic tool called a "Duct Blaster". It is specifically for measuring duct leakage and related problems. Ducts average 15% leakage. It might give you a less expensive way to enter that market and refine your presentation. Home Energy magazine has printed a lot on duct blasters and blower doors.

Yours, Larry

Darin Cook_3

You guys are talking about

what the Energy Star program in NYS does now. When we were involved in the program a few years ago you had to do all the blower door testing, combustion appliance zone testing, duct blaster if warm air, test the stoves and ovens, insulation imspections, lighting inspections, all for $100.00 . CSG had a IR camera they would bring out upon request. The whole energy audit took about 3-4 hours and all your time to input information on the CSG website back at the office. They now allow you to charge $250.00 . Think you had to get a sale to make it worth your while? Oh yeah, you had to refund the $100.00 if you closed the sale!
As some people said above if you are not testing the ACH or really know what the insulation package is, YOU ARE STILL ONLY GUESSING AT THE HEAT LOSS NO MATTER WHAT SOFTWARE YOU ARE USING!!!!!!! Heating is an exact science its just that none of us in real life circumstances, can really do it exactly. But we can get real close!








Darin

Bob Harper

multiple uses

You can perform Energy Rating to assess the plans and specs, do on site pre-drywall inspections, then blower door test to prove the overall package. There are programs such as Energy Star and there are "energy mortgages". Some utilities will sell power at a reduced rate if your house is tight and efficient enough.

If you have houses that have CFM50's up in the thousands, then there's not much sense spending any money on new heaters and such until those barn doors are closed. A house that needed a huge boiler, say 1.5 gph of oil might be brought down to a 0.85 gph burner w/ new efficient boiler in the same house if properly weatherized.

ASHRAE 62.2 calls for at least 0.35 ACH--not 25 ACH!! Wow, those homes are sieves!

You can use a blower door to guide selection of heaters and weatherization to address total comfort. Don't get sucked into just heat or just air infiltration or any one aspect. You need a holistic approach and the blower door with IT thermography gives you that.

The Minn. Blower Door has a new automated testing system where you can attach sensors for CO, air temp, Rh%-up to 8 channels and record them while you put the house through its paces. This is an advanced form of a Worst Case Depressurization Test, which every home with atmospherically vented equipment needs.

With the whole package, you can find and guide those leaky ducts, seal upper level leaks, provide adequate makeup air down low so appliances don't backdraft, and improve comfort. The IR camera can also find water leaks in walls & ceilings, hot electrical circuits, sore knees, and many more uses. There is a cheap camera out for about $10K but you have to colorize the images. A good IR camera starts around $50K and you need to take the certification to do it right.
Bob

Tony_23

Where are you located ?

18 ACH/hr ! HS ! I've seen chicken coops with less !

GW

Christain

You must have been rocked by some slick salesman recently because I don't know where you got the impression anyone here is gold digging like some lame ambulance chaser. You mean to tell me you've never talked with a home owner with a brand new home that was completely frustrated with their new home's heating or cooling system?

I'm just trying to say out of a hundred homes built a tiny fraction may have quality construction elements, proper air barriers and higher-end HVAC (the list goes on, but you get the point). The kicker is the general public has clue zero about this. My point was if someone (probably not me because I'm not a marketing genius) can get a message out there, the whole industry may climb up a few rungs on the ladder, because it will be common knowledge that there's crappy stuff out there (It's not common knowledge now). If the whole industry gets more professional, I'll probably make more money to stick more food in the family's mouths (not that I'm complaining about my current income).

Also, the insurance example? Dude, just cancel your policies if you're anti-insurance. That's a pretty lame example, don't you think? I can't think of any reason why you're bugged about blower door testing and specialty diagnostics other than maybe you can't rise to the occasion and commit to getting yourself to the next level.


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GW

Unhappy with some comments

1. I agree with that.

2. I said I can have mine running in 10 minutes, who on earth can do a complete test in 10 minutes?

3. I will complain to the people I bought my Retrotec from, shame on them. This reminds me of the little brat on the back of people's pick up trucks, you know, the little guy peeing on the "other" logo.

4. Comfort Institute has great class room training and the most personable hands-on in-house field training I've ever experienced in my 16 years of business. So, can I say I have training or what?

5. I get a bit more.

6. Now I see why you hold yourself in such high regard, we're "just" the HVAC guys, or so it seems.

7. If I did the testing myself, I wouldn't need you, I would document my findings and if the numbers looked bogus I'd have them certified mailed to the builder, cc to the new homeowner. (I haven't done that yet)

8. I have all my design parameters in the proposals, that is I'm telling the customer what ACH in the summer I'm designing to, and how much in the winter. There are clauses up the kazoo; canned lights that are not sealed, knee walls that are not covered tightly on the back exposed side of the wall, fresh air elements, combustion air for even their fireplace, so on and so forth, it's pretty thorough.

You seem like a smart guy, but if you're going to hang with the heat dudes could you give us some slack? Happy holidays,

Gary


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Bob Morrison_3

How often? (BM)

Mike,

You mention that you work on behalf of a few, repeat HVAC installers - do you have an idea of how frequently they need your services? Maybe 1 of every 20 of their projects? Based on your experience, what do ACH do you recommend for a new house residential HVAC load?

Thanks

Bob Morrison

Mike Thomas_2

My Apologies

Sorry if I offended anyone. I also do HVAC work. I spent 18 years in Alaska. I did commercial refrigeration and restaurant equipment repair and installation. I also did lots of residential boiler system design, installation and service. I worked on lots of computer room systems that heat,cool, humidify and dehumidify. I also designed and built 17 homes. I monitor this site on an almost daily basis and learn something every time. I seldom comment on threads, because I feel that most of the time you guys are so far ahead of me that I'll never catch up.

When I retired and moved back to Iowa, my wife made me promise that I would not have a business that called me out at all hours of the day or night, but I still like to sneak off a do a nice radiant heat job now and again.

When the subject of blower doors came up, I felt that some of the comments left out some important backround information. I tried to fill in the blanks. For example, "I can have my blower door equipment up and running in 10 minutes..." is very accurate. But the whole story for a person who has never seen one done, is that it can take an hour or more.

I also tried to show how HVAC contractors and vendors use my experience and sevices to show customers that they did everything right, and the general contractor, the guys that built the house screwed up. I try to be the "third party" that helps settle who is really responsible for why their house won't heat or cool properly.

HVAC contractors will use me maybe once every two years. The vendors will call me maybe a couple times a year.

Again, I apologize if I offended anyone. I do the same work that you folks do, radiant heat, I just add blower door testing to my bag of tricks.

Mike Thomas_2

How often

Contractors will use me only once every couple of years. It is only when they get in trouble on a new house or commercial building that they can't heat or cool. They know the first thing I ask for is to look at the numbers they used to design the system. They are all very good at what they do, but if you get shoddy construction on the building envelope, your dead in the water.

Vendors really like it because they supply the equipment and if things aren't working, they almost always get dragged into the deal.

In Alaska we shoot for 1 and 1/2 air changes per hour at 50 pascals. 50 Pascals simulates a 20 mph wind on all sides of the building at once. Here in Southern Iowa I see a lot of 4, 5, & 6 air changes per hour, but guys are talking about it and I expect numbers to go down as techniques and materials are adopted. I am president of the local Home Builders Association so I get to visit with lots of contractors. Change happens slow, but at least many of them are asking how to do things better.