Can the first story of a slab on grade be liveable in cold climates?
2-story SOG house in climate zone 4.
The downstairs is finished (fibreglass batt insulation in walls). I believe no insulation under slab or perimeter.
No moisture/water intrusion from slab. No significant cracks. Drainage around the house is good.
Having reviewed a lot of the posts on the forums, I’ve checked:
1) No CO detected.
2) No radon.
3) Gas fireplace downstairs. A thermometer reads 72 F while the fireplace is on low. Ceiling fan is on to circulate the air.
Also, the forced air system (shared for both floors) has one return vent and several supply vents (all on the ceilings) spread throughout the living space.
4) I installed 1” EPS subfloor (Dri-core) and laminate so the floor is now OK at retaining heat.
5) Humidity measures the same upstairs and downstairs, 47%.
I read that most of the heat loss in a slab on grade is on the perimeter. Is this what’s causing the comfort issues?
I used an IR gun to measure some areas in winter: 55F on the bottom of the wall downstairs, at eye height the wall measured 60F, the floor with the fireplace on measures 62F. The bottom of the wall upstairs measures 68 F.
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>Anytime I or my family stay downstairs, we get a weird feeling in the chest/abdomen. It’s a feeling that makes you want to cross your arms to alleviate the pain.
This doesn't sound temperature-related at all.
I think it must be the downstairs materials. For comparison, I'm on in a 1950 slab ranch (zone 5), my wife has asthma, yet we have no problems now. For saying it must be materials, we have no insulation in the walls and nothing, including a sealer, on the slab. (we do have wool wall-to-wall with the 3/8" open cell pad on the floor). I wonder about your Dri-Cor on the floor. Isn't there a test for determining the level of VOCs in your house?
Originally our problem was moisture coming up through the slab. We had some mold. In the summer, to use the printer, we had to nuke the paper in the microwave first. AC and a whole house dehumidifier solved the problem. We have been living comfortably, and apparently healthy, for the past 13 years after the AC and dehumidifier went in.
Your situations sounds horrible. Best of luck.
Laminate can also off-gas.
Consumer-grade IAQ monitors have a poor record of measuring VOC's. I don't have a specific recommendation but that and particulates seem like what you should be looking at. If you're not measuring you're just guessing.
Thank you and to DC for the feedback.
The issue was there before Dricore. I put it in hoping to solve the problem but that didn’t pan out.
Both of you seem to think it’s not temperature related so it points me in the direction of mold/moisture. I’ve ruled out mold except where masonry chimney meets drywall and siding.
Will look into VOCs as well.
Maybe you should call a priest.
nynick,
Hey, hey now.
That's not an appropriate comment. While it may be ok among friends or the internet in general, GBA should be a safe space for everyone to ask questions without being ridiculed.
“Can the first story of a slab on grade be liveable in cold climates?”
The answer to this question is Yes for of millions of people in millions of homes.
Do you have any measurable clues?
If all you have is a mysterious gut feeling I don’t see how we can be helpful.
Run a double-blind test in which some without knowledge of your concerns explores the home in your absence and afterward is asked about how they physically felt in each room.
Have you ever been under the under the care of a psychiatrist?
Walta
Walta,
"Have you ever been under the under the care of a psychiatrist?"
These kinds of comments have no place on GBA.
That's not an appropriate comment. While it may be ok among friends or the internet in general, GBA should be a safe space for everyone to ask questions without being ridiculed.
Fair play Walta and nynick. I did my best to resolve the problem to avoid the expected response!
I had someone mention chest soreness unsolicited while staying over.
Was looking for feedback from anyone in similar climates before I go the route of perimeter insulation of the slab.
A lot of posts mention radiant heat for slab on grade so I was jumping to the conclusion that it’s temperature related.
Why on earth would temperature make your chest tighten? It just makes no sense at all.
Tell me more about your gas fireplace. Is it vented to the outside? If so, how?
Do you experience the feeling at all times of year, or only during heating season?
It’s the same year round.
Free standing gas stove with ceramic glass drawing air from the room, 90s model. Clean chamber.
Its vented using a 5” vent through the masonry chimney. This stove has a separate cap from the cap for the gas logs that are upstairs but shares the chimney.
If it's the same year round, that points even further away from a temperature issue. Does your chest tighten up when you go outside and it's cold? I suspect not. It's not a symptom I've ever heard reported, whether it's 0C or -40C. People work in uninsulated, unheated buildings with concrete slabs all day long and this is not a complaint they have.
Nick and Walta are both being quite rude.
I, for one, find mildew smell quite affecting. I have also found that many people seem quite unable to smell mildew at any level. Two local buildings are noticeably rank to me and one does cause me to feel like my breathing is restricted. I avoid both. My attempts to call attention to the odors in both cases fell on deaf ears. My ability to smell mildew is not cause to call for exorcisms or question my sanity.
My wife is chemically sensitive to things I have no problem with, like chip board. Off gassing from new particle board is certainly a relatively common problem. Some people react negatively to the fumes far longer than others. Unfortunately, due to highly unpredictable responses to such irritants, the chance of finding others that will experience the same feeling as you might be dicey.
As others have noted, consumer air testing gizmos are of pretty questionable value. Finding and affording truly valid testing procedures might not be easy or as useful as one would expect. The forced air system should be mixing all the air over a relatively short period of time, but without knowing where the vents, return and the furnace are located it is difficult to discern if you have dead spots. If air testing is done after the system is off for 24 hours it might be possible to pick up the differences between floors. And it is a guess as to what to look for.
You might look at the gas fireplace more closely. You have tested for CO, but that will not necessarily rule out partial combustion elements. Perhaps the paint or other finishes in the fire box are off gassing or perhaps any sealants used during installation. Long shot since you seem to have been in the house for some time. And again with fan and forced air the same effect on you should present upstairs.
The low temps at wall and slab junction suggest potential condensation issues at the sill plate. The addition of the dri-core and laminate may help your feet stay warmer, but you have removed the room heat available to the slab. The slab is now colder than it would have been before and possibly a new and larger condensation surface. Despite the perception of good drainage, it is quite possible that the slab is transpiring ground moisture as would be the slab perimeter.
This brings back the mildew issue and why upstairs you don't experience it. The walls are simply warmer and you don't have the sill to slab air leakage nor the moisture potential of the slab. You don't mention if what you experience is a year round effect. IF it is, I would suggest peeling off a section of baseboard on the outside wall near the fireplace and checking the back for mold. After that, an exploratory look at the back of the drywall. If you can find two studs and cut on the center line of the studs, it will make replacing the patch a bit easier.
Removing a section of drywall will also allow for assessing the moisture levels in the insulation and the sill plate. You might find black spidery web mold or the dark gray cotton ball like mold I have encountered before. There are many mold types and many levels of reaction to them. At that point, you need to assess if your insurance has a mold exception. Mold remediation can be very costly.
Thank you for the detailed response.
It’s a year round effect.
When I installed flooring I saw the baseboard by the fireplace had black marks. I took off the drywall 2’ from the ground and two studs worth of width. Found black mold. Drywall was replaced. Batt insulation was ok but bottom sill had 5” section with some rot. I took of the rot and applied epoxy to seal.
May I ask your suggestion: from what I saw there’s still one stud bay to reach the chimney. I couldn’t access it because there’s brick covering that section of drywall. Would you take off the brick from the inside or try to get at this through the outdoor siding? It’s fiber cement siding.
The information that it happens year-round is valuable. It means it's not the heating system.
The fact that you've had mold in the past does make mold a suspect. But you've got to test, otherwise how will you know when you've fixed it?
Mold means moisture and moisture means mold. The possibility I would exhaust before looking anywhere else is that rain is leaking in through either the roofing or the siding. Finding rot near a chimney means there's a very good chance that the boundary between the chimney and the siding is leaking.
Mold seems like the most likely culprit. Even if you have it professionally remediated, if you don't change the conditions that caused it to grow in the first place, it will come back.
I would also consider getting a monitor that checks VOCs and carbon dioxide levels. I have an Awair monitor that is relatively affordable.
In answer to your title and not the post, yes. I know people with slab on grade homes in zone 6, which is much colder than zone 4. The most comfortable homes use hydronic in slab heat.
And kudos to you for your efforts in trying to fix the issue. Homes are typically your largest investment and your families' health is the most important thing. Doesn't matter the cause.
"The most comfortable homes use hydronic in slab heat."
You're much better off building the house to be comfortable in the first place with complete insulation and air sealing than trying to compensate with the choice of heating system.
Maybe I should have been more precise and said perceived comfort. It's feedback from the people who own them. Even if the air temp is comfortable and not drafty, many just like the warmth below their feet.
Your observations are not abnormal at all, and as others have alluded to, may or may not be directly related to the physical properties of the room. Is the space oppressive? Are the ceilings low, and windows high and small, what you describe is exactly the same reaction my wife had to our previous basement, she swore there was mold, although there was never a physical mold problem, she couldn't stay down there for any length of time... And when she did, she would cross her arms as if she was cold. I had no issues, the kids had no issue.... Her mother had COPD, and could not stay in the guest room downstairs because it would cause instant anxiety and panic. Her sister, who my wife spoke with daily, finally visited and also felt the space was unhealthy. We sold that house about 10 years ago, and at that time I was also convinced something unhealthy existed down there. Her son bought a house in Pueblo Co 2 years ago, it had a basement guest room we were supposed to stay in, with 7' ceilings and two small, high, basement windows. Upon seeing it, I thought it was a beautiful dry modern bedroom... that day, looking over at my wife, she had her arms folded across her chest and a look on her face that I instantly recognized... She had that unhealthy feelings again, and there was no way were staying down there. It was then that I wondered if perhaps these feelings of breathing anxiety, chill, chest tightness, are likely more related with the realization that she was expected to sleep/stay down there... She can easily visit such rooms with no anxiety, but if we were get a basement hotel room it wasn't going to be a situation where she could sleep. A trip to Ireland verified this, we could visit and enjoy many pubs, castles and tours with dark low and oppressive subterranean rooms, but if the hotel had a confined room in a basement, she would pick up an unhealthy smell/nature/feel to the room and we would have to make different arrangements. I think it is tied to the knowledge she is expected to sleep or stay down there vs shortly visit or pass through... It certainly has nothing to do with religion or spirts, and if its not a real health hazard she is attuned into, then its more likely a general oppressive feeling brought on by the knowledge she has to sleep/live below ground level. She is a very pragmatic person, a realist to the core, and is very insistent is more than simply "mental". In the end it doesn't matter, if you don't feel like its healthy, then it truly is not healthy...
So which expert is needed? A psychiatrist, or a priest?