Insulation experts - need some help!

[trailwart]

"I should note that the systems isn't running much with the 43 thermostat setting. I prefer to keep it 58 in there, but that's when it was running a lot so I turned it down until I resolve the issue. It could sustain 58 when the outside temps were in the upper 20s or higher. It's when we got around 0 to teens when I started having problems. I think just a little more insulation should do the trick."
your system does not run much on the 43 setting because it is capable of maintaining that temp, you prefer 58 but when its cold the system cannot maintain and is running excessive and not capable of your demands as it sounds that your heater is undersized

"I agree that you can't make it 80 inside if the heater can't put out more than 80, but mine can put out more than enough when the temp differential isn't as great."
seems you need to work in warmer weather, or upgrade the heater to compensate for really cold days
"If the in/out temp wasn't an issue, why does the temp inside change when the heat is turned off?"
when the heat is turned off the air will eventually equalize or close to it with outside temps

"I'm sure I could get the slab to 70 if I tried (not at -10 outside though), but it would be warmer than my target temp in the shop."

you should be able to get the slab 70 or even 80 degrees no matter the outside temp if you have the proper heater for the system

looking at your temp comparisons/logging on the first page seems like the floor temp is within a degree or 2 from floor to ceiling. the system seems to be able to handle 43 pretty easy. it really sounds like your demands in 0 or colder days is exceeding the heaters capability. the main reason i still think the heater is the issue is your having problems getting floor hieght temps where you want them in cold-cold weather.

 

[jeff5295]

when the heat is turned off the air will eventually equalize or close to it with outside temps

I realize this. Sorry, I was being sarcastic when I asked my question because a statement was made eluding to the fact that outside temp was irrelevant. It certainly plays a big part.


I appreciate all the advice from everyone, but for now I'm sticking with the heat source I have. A lesser heat source in my old shop produced excellent results (while turned down to it's lowest setting I might add). Whether everyone agrees with me or not, I think we can all agree I need more insulation.

It would be foolish to abandon my current heat source when I know insualtion is a concern. That needs to be addressed reguardless of heat source.

We've strayed pretty far from the original question.

I started this thread asking for insualtion advice from experts who may have experience with a similar building style.

So, I'll ask again. Does anyone have any creative, innovative, alternative, etc... ideas to insulate the underside of a roof?

If money were no concern, I'd get 3" or 4" rigid foam boards, screw them to the girts under the roof, and cover it with white ribed steel.

Not enough cash right now to do that so I'm looking for other suggestions that would not require follow-up work after the panels are up (no mudding, sanding, painting etc...). I have a huge area to cover and I want something simple that I can just install and be done. I can go back and add some sort of covering later if I can't find an insulation and finished ceiling all in one.

As said before, I can't add a traditional flat ceiling.

So anyone else run across this situation? Let me know what you did.

Thanks!

 

[airbassador]

Put on a sweatshirt, you daisy!

All kidding aside, just getting some kind of ceiling up and getting a buffer above will do wonders for keeping you warm. I hate mud and tape too, how about laying out a grid and panels and do a dropped ceiling like a commercial office? Or T-111 and paint/stain it? There are also some thin tongue and groove pine products at the home stores, but they may not be able to take the weight of fiberglass bats.

I recently did had the same situation in my house. We had open truss in the 'great room' because it looked cool, but after burning a cord of wood a night in winter to keep warm, I put up tongue and groove. No insulation yet, but it's a heck of a lot better.

 

[jeff5295]

Put on a sweatshirt, you daisy!

All kidding aside, just getting some kind of ceiling up and getting a buffer above will do wonders for keeping you warm. I hate mud and tape too, how about laying out a grid and panels and do a dropped ceiling like a commercial office? Or T-111 and paint/stain it? There are also some thin tongue and groove pine products at the home stores, but they may not be able to take the weight of fiberglass bats.

I recently did had the same situation in my house. We had open truss in the 'great room' because it looked cool, but after burning a cord of wood a night in winter to keep warm, I put up tongue and groove. No insulation yet, but it's a heck of a lot better.

Thanks for the suggestion, but as stated earlier I can't do a flat ceiling (I'm using some of the area as a loft and I'm not sure the trusses were designed to handle the extra weight to have ceiling and insulation).

All of the research I've seen shows that ceiling height in a radiant slab situation is somewhat irrelevant anyway. If I were using air heat, I agree, I would need to lower the ceiling.

 

[jeff5295]

Just thought I’d provide an update in case anyone finds this post and wondered how things turned out.

I ended up stapling 4mil poly to the underside of the upper truss cords, then used 2x3 stringers every 3 or 4 feet to provide support and a place to eventually screw my ceiling material to.

I then blew in fiberglass ceiling insulation, filling the cavity to the roof steel. This provided about 10-12” inches of fiberglass in addition to the existing spray foam on the underside of the roof.

The decrease in how often my circulation pump and water heater ran was immediate and huge.

It’s getting warmer here over the last few weeks, but I completed this job the first weekend in Feb and we were still seeing highs in the 10’s-20’s F and lows below zero F regularly.

The heater used to run constantly through the night and still ran a lot during the day. It now almost never runs during the day and runs considerably less at night. The pump and heater cycles are much shorter and I was able to turn the water heater temp control down to just above its lowest setting. I’ll probably put it on the lowest setting now that it’s getting warmer outside.

For those who commented that my heater was too small and my ceiling too high, it’s not true. The system works as expected now and the ceiling height difference from my old shop appears to be practically irrelevant, as I figured it would be.

I may take a similar approach on my walls and fill them with blow-in fiberglass as well, just to give it the ultimate insulation value before I install wall coverings. It’s probably overkill, but it will be my only chance to do it.

My biggest heat loss now is probably my OH door, as it was not insulated when I bought the property. I had spray foam applied when they did the walls and ceiling, but I’m sure it’s not as good as a factory-insulted door. Eventually I’ll replace it, but a new 16x12 door was going to cost $2500 - $3000 and the spray foam cost $300. I just didn’t have the extra money at the time.

If I had it all to do over again, I would’ve only had 1” of closed cell spray foam applied to walls and ceiling to seal up the building, then applied the blow-in. It might have saved enough for me to buy the replacement door. Lesson learned.

The shop is now well seal and comfortable. Now I can get back to working on my cars.

Hope this info helps someone else considering a similar situation.