Negative air pressure/Desperate for help

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So all three air suckers are located in the same location? Where?

Oops! Sorry Brian.
What he said…

The picture I’m starting to build is you closed up the air leakage of the house (insulation and other stuff in the report attached), added another appliance that requires more outdoor air, which was not CAZ tested (see report), and no pressure testing was done of the house with reference to the exterior to determine building pressures. I’m getting the impression that a lot of work was done to the house to go above and beyond normal house efficiency. I often find that people think that if a little is good, a lot will be better. I am not convinced you are aware of what is actually going on right now after all this work. If you are, you’re not providing the information we need here. The HRV should help equalize building pressures that were created from all the other work you had done, specifically that insulation in the attic perception.

The picture of the HRV you posted with arrows, shows perceived airflow directions. The HRV transfers heat through counterflow duct design.

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Your pic shows parallel air flow?

When we fix things, we look at a specific problem to correct. You’re coming at this from all directions. What is the specific problem? Air pressure? What is the building air pressure?
Building efficiency, air quality, health issues, appliance operation, comfort? You talked about them all.
Which single one is the problem. All the other stuff are issues because of the problem.
You need to test for that one problem. Don’t be tunnel visioned with that insulation thing. Several people here can’t perceive that as being the problem you describe.

You are also hug on “stack effect” as being the cause of pressure differential. Well, you have not convinced me or others that is the case. What do you have to document that?
If you don’t have anything, get someone in there with a micro-manometer and test pressures with all the scenarios under normal use of the house. Test with one system operating at a time.

You mentioned appliance back draft only one time? Your report said there are no appliances to test for CAZ?

Woodstove also in the full finished basement.

More bits and pieces come to light… :flushed:

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It looked to me that the HRV was in the basement, but perhaps no inlets or outlets to the ventilator were installed in the basement. So, the basement is still potentially a confined space if that is were all the gas-fired appliances are located. She implied that her negative pressure issues and backdraft (of one of those appliances) occurred after she replaced the electric water heater with a gas-fired one. The insulation in the attic is just coincidental IMO.

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Hay Robert, I know appliance combustion air quantity has not been answered, but consider that this information alone will not solve anything and is actually worthless information at this point.

Consider what causes CFM. Pressure differentials. If there is no pressure differential, there is no air flow. You can leave a window open and no air will pass w/o pressure.
Pressure differential is from natural or mechanical forces. ie. Stack and wind vs. fans.

400 what at 50 CFM?
More miss-perceived information. :thinking:

Don’t you think?
Testing build pressure changes while turning on each appliance individually is actually what we need to know. You will have high pressure with low CFM. High CFM will not create high negative pressures necessarily. Getting high CFM with high pressure will just leave us with a bunch more unanswered questions. They are already 2 yrs into this, because of this…

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Did anyone check to see if the attic space was ruptured enough to allow a comingling with habitable space air and insulation? The attic is unconditioned sperate space.
PS: I hate those Styrofoam venting baffles. They collapse when insulation is bumped up snug against the baffles. As well, not enough clear open area to move air from the eave to the attic.

The OP writes, “This vapor matter which carries with it the insulation and other materials has filled all carpeting in every single room, furniture, bedding, ect as they are all acting like sponges.”

Are we to understand there is vapour? Need RH readings.
If so, likely bathroom or/and kitchen hood top vents are not functioning properly, and how does it carry insulation material?
As for vapour, a HVAC duct is the conveyer?
A venting specialist might be able to track down the leak.

So, Negative pressure occurs when there is less air in your home than outside. What about make-up air?

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Wow, impressive shocked with all of the responses here, something I’m definitely not used to receiving. I’m glad i picked a good site to discuss this, maybe i will finally receive some real answers. I feel quite like i don’t know many of these answers after all when i thought i did. Both from my own constant researching, as well as what I’ve been told.

In my opinion, this water vapor that is very evident as i take videos with my phone anywhere in the house, watching it seep out of baseboards and see the worst of the rooms to be my laundry room, is coming from the dryer itself. If my dryer is too backdrafting as the other two appliances are, wouldn’t it make sense as to where this vapor type of matter has come from? My clothes come out too hot to touch upon a cycle ending. We conducted simple “toilet paper tests” with holding them to the outside venting of the furnace and water heater, as well as around the fan of the gas powered water heater inside, to have them all show our peices of toilet paper being sucked up to the exhaust pipes all by themselves. More so upon the kitchen range and bathfan being turned on. The toilet paper peice we held up near the fan of the water heater inside of the house started blowing outward. This water heater seems to be pulling air in when its not even running. CO2 levels are high anywhere i go in the house as i took readings with an air monitor i received from my furnace company to use for some time.

The state health department toxicologist took samples from my home and i cut out a peice of carpeting for him to test as well. He came back after his months long testing to deliver me a 30 page report, showing his findings to be cellulose insulation in the carpeting. I believe there has got ti be much more than that as i see a glittery substance in carpeting in every single room as well. There are fiberglass batts underneath of this cellulose insulation, perhaps that may be the glitter I’m seeing, or the borate from what I’m told as that is in cellulose insulation. I have also been informed there is cellulose in dryer lint. My return vents became covered in a thick layer of what appeared to be dryer lint after we were told to attach screens to our return vents. We had to clean these every 3 weeks. We have since removed the screens as we were told to let the furnace filter catch everything instead. My home is dusty, becoming covered in a thick white layer, some rooms more so than others. It surely appears to be my dryer being the culprit. And yes we have certainly made sure the venting is fully cleaned of any lint or debris. Numerous times. As well as added a hood of some sorts to the area that vents outside. This was also touched by that weatherization program as they added a peice on the outside of the house where the dryer vents, with a “flapper” attached to it. That has since been removed as we now have added that “hood” of sorts to the area that vents to the outside. Over the summer i noticed a heck of a lot of lint had been blowing out of there onto the ground.

Photos of my furnace and heat exchanger appear to be so moisture ridden, it looks like a smog filled mess in there, with debris as well. Corrosion is what it looks like, with bits of black stuff that has a distinct shape to them. Which are the exact substances i am seeing in my carpeting and vacume. Just so you’re aware, our A coil and entire AC unit was replaced last summer. Due in large part to not being able to keep up with dehumidifiing the house i believe. Our electricity bills have never been higher, and are still to this day showing as being 60% higher than previous years. We have also went through nearly triple the amount of LP.

The woodstove is not ever used, and has been sealed at the top area where the venting meets the ceiling and leads to the attic.

By the way, this furnace is only two years old, also being replaced by the weatherization program.

I will post pictures next, hopefully this will help in your abilities to diagnose these issues.

Thank you, i certainly appreciate all of the comments and questions that help to try to figure this out once and for all. If i missed any questions please ask away. I will do my very best to reply to each of them.

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RH readings are around 30 this time of year but I’ve seen it as high as 70 as it read in my laundry room during the summer months. The fruit cellar, which is always colder, became humid the first year this started to occur. The floor in the laundry room is painted cement and shows many areas of staining in odd areas and markings of lines. Like air flow trails, which is exactly what is occurring in my carpeting in every single room, air flow lines of this stuff, packed with the sandy-like substance that is every where and in everything. These lines come from the walls as well, and also run along the lines of the marriage line of our modular home. Perhaps this negative air pressure has caused air to flow backwards from the attic up through the marriage line? This does lead to the attic somewhere, correct?

Attic space ruptured enough…i do not know. The only thing i know is there are baffles crushed and soffits blocked completely.

Carries insulation perhaps from negative air pressure and the attic left unsealed?

Not nearly enough make up air i take it.

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Sorry I do not know all the answers to these mysteries. This is why I’m here, to obtain help no one can give me for some reason.

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Home Page | buildingscience.com

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Is this thing not installed correctly? The ERV? This has been mentioned previously by someone, then again the Renewair company says its perfect. :woman_shrugging:

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Appliances are backdrafting still to this day. The water heater upon it not running is when this occours. More so when fans are turned on such as bathfan and kitchen range.

Documentation from what I’ve learned from what the company who had been in my attic stated with the feeling like s vacume as he dug down in the cellulose was a large clue i had precieved.

That document showing there was no worst case draft testing was from the company who installed this insulation and water heater. I know enough to know they should have done that test. It would have told them we do not have enough make up air.

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Watch this it may help you. Building Science 2 of 2 - YouTube

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I tried calculations for BTU amounts and i don’t know what I’m doing. I did take these photos of my laundry room though. Where all three appliances are at, furnace, water heater, and clothes dryer. Also ERV.

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For sure the furnace and water heater are backdrafting or pulling air backwards from our owb testing. Please read my posts that explain this in more detail.