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OT - Shop insulation

That boiler ran 50 percent average duty cycle in Oct/Nov.

Come February that is not going to be pretty.

Since I would think you thermal losses are about half your actual use, it points to infiltration[air leaks] or system problems. I suppose an underslab water leak might cause it, but the odds of it going undetected seem slim

All these calculations assume an empty building. Remember that most of your electric bill ends up as heat.

Funny you get mad at me. I am the one saying maybe you didn't make mistakes, but someone else[IE contractors] did.
 
In general one would not see that kind of heatloss through a floor, as unlike the air, the heat does not go away. It heats the soil which stays warm.
I've never designed anything that needed to consider heat load through a slab and definitely not something that has radiant in floor. Reading up a little more, the F-Value for R10 slab would be .55 with 380ft perimeter. This works out 5713 BTU/hr going out the slab instead of 16K (10.5K at the 10F design temp). This further emphasizes the potential to make improvements to the enclosure. The design of the slab perimeter and stem wall (if there is one) insulation should still be reviewed as they can be areas for large heat loss.
1669485026050.png

The contribution of electrical loads is likely significant if this facility is doing real work. This is likely masking the effects of significant infiltration I don't see showing up in my calcs.

That boiler ran 50 percent average duty cycle in Oct/Nov.
Duty cycle is irrelevant in heat loss analysis unless you are concerned about capacity or short cycling. I don't think either is a concern here. 701 Gallons over 33 days is 40.7% capacity.

I think the point has been made that the OP should be humble with regard to what it takes to build a nice building in a cold climate. There is nice freedom in not having to meet code, but there is also a lot of responsibility with that which the OP is eating now. I think enough justification has also been provided that a $20K investment in upgrading the building is not unreasonable. This isn't really a project that will get done correctly on an internet forum without a knowledgeable OP.

OP needs to get reading or plan to higher a pro. The correct pro is someone who is not tied to any of the installation companies. I have never met an installer of insulation or HVAC that can correctly do heat load calcs and cost benefit analysis. I'm sure they exist, just rare.

You might reach out to these guys to see if they have any recommendations in your area:
 
Duty cycle is irrelevant in heat loss analysis unless you are concerned about capacity or short cycling. I don't think either is a concern here. 701 Gallons over 33 days is 40.7% capacity.
read my whole quote.
my point was this is November
In February, it will be way, way over 100 percent capacity IOW, cold
My whole point , over and over here, is that the shell, all 14020 square feet of it, should only lose that much heat at design temperature, around zero F. Not at 34 degrees.
Certainly the building is underinsulated, but even quadrupling the insulation will not solve this problem
sq ft * DT/ R usually overestimates actual heat loss. It is good enough to size a boiler, but not to calculate fuel use over a season. So when I say a Delta T of 30 degrees should use just over a third of that fuel, it says to me that something else is wrong.
 
read my whole quote.
my point was this is November
In February, it will be way, way over 100 percent capacity IOW, cold
My whole point , over and over here, is that the shell, all 14020 square feet of it, should only lose that much heat at design temperature, around zero F. Not at 34 degrees.
Certainly the building is underinsulated, but even quadrupling the insulation will not solve this problem
sq ft * DT/ R usually overestimates actual heat loss. It is good enough to size a boiler, but not to calculate fuel use over a season. So when I say a Delta T of 30 degrees should use just over a third of that fuel, it says to me that something else is wrong.
If I update the HDD to cover the Oct. 17th - Nov 19th I get 809. With an annual 5570 HDD, that works out to 4634 gallon or $11,121. It would be interesting to know how that compares to the gallons used last year.

Using the updated numbers, heat loss for the building is 3172 BTU/H/Deg.

199,000 BTU/H / 3172 BTU/H/Deg = 62.7F delta to run out of capacity.

Coeur D'Alene Airport is used as the location for Bonner and has a 99% design temp of +10F. No capacity issues if that is true. OP has been through one winter, so they can let us know if they ever weren't able to maintain the 60F setpoint. Someone more knowledge of the local area could likely pick a better reference:

This is a load calc using actual fuel use, which is generally accurate at predicting total fuel use. It will also provide an accurate capacity estimate without the overestimate seen from of sq ft * DT/ R.

If I assume the enclosure is performing at the table listed total wall R Value of 7.2 and using the updated floor load, I get that you would need about 900cfm of infiltration to match the fuel usage based actual BTU consumption. That is a LOT, but not unheard of. But ton of infiltration along with some missing insulation in areas like a stem wall would do it. Increasing the total wall R value will result in significant savings, particularly because the smart approaches will also address infiltration. The focus on total wall is super important, 4x insulation in the bays will barely move the needle.

It is still worth checking for weird things like leaks in the loops. I would also review where the moisture barrier was placed relative to the sub slab foam. If they happened to place it below the foam, the slab can be sitting in a bathtub. Putting the plastic below the foam makes it seem like the foam will stay dry, but it instead it traps water in the foam.

Regardless of any calculation details, it is clear this building is pissing away fuel. We aren't going to fix this here though other than to push that they need someone who can analyze the situation on site. There are just too many things to cover. A blower door will give the real infiltration load, identify the major leak sources, and spot major thermal issues.

I believe code compliance still may be required where the OP is, even if there are no inspection. It is the builder's responsibility to ensure code compliance (at least where I am), so there might be some avenue for legal action. I would imagine the builder would only be responsible for the additional remediation costs beyond what it would have cost to build it right the first time, so it may not be cost effective.
 
In general one would not see that kind of heatloss through a floor, as unlike the air, the heat does not go away. It heats the soil which stays warm.
The soil soaks the heat out of the slab.... it's like you laying on a cold water bed...you'll never get it up to your desired temperature!
That's why the rigid foam board beneath, right? You might warm up a few inches beneath an uninsulated slab, but there's an infinite number of miles of earth beneath that that will continually draw the heat away.

I had a friend who built a house on a slab, pex in the slab. He didn't know enough back then to insulate UNDER the slab. Lucky for him, he had a waste oil burning boiler... and nearly unlimited supply of oil...so it didn't really faze him to go through lots of oil keeping the earthworms warm.

A farm equipment dealer near here... they did in-slab hydronic heat in the newish shop they have. I was up there buying parts one day and found out they had hydronic heat.. I asked if I could look at their set up. Waste oil. I asked how it worked... said they used a lot of oil. I asked if they insulated under the slab... "no".
"Well, there's your problem, lady"....
Truth in advertising: I have hydronic heat... but by way of baseboard type radiators.
 
The soil soaks the heat out of the slab.... it's like you laying on a cold water bed...you'll never get it up to your desired temperature!
That's why the rigid foam board beneath, right? You might warm up a few inches beneath an uninsulated slab, but there's an infinite number of miles of earth beneath that that will continually draw the heat away.

I had a friend who built a house on a slab, pex in the slab. He didn't know enough back then to insulate UNDER the slab. Lucky for him, he had a waste oil burning boiler... and nearly unlimited supply of oil...so it didn't really faze him to go through lots of oil keeping the earthworms warm.

A farm equipment dealer near here... they did in-slab hydronic heat in the newish shop they have. I was up there buying parts one day and found out they had hydronic heat.. I asked if I could look at their set up. Waste oil. I asked how it worked... said they used a lot of oil. I asked if they insulated under the slab... "no".
"Well, there's your problem, lady"....
Truth in advertising: I have hydronic heat... but by way of baseboard type radiators.
Actually it doesn't really do that. First, everything is an insulator to some extent, some are just good enough we call them insulators. So soil is to some extent, an insulator. Running water under the slab would be problematic, but the soil underneath does indeed get warm and stay warm, unlike outside air.
I love radiant heat, I grew up with it. Uninsulated slabs in little ranches were pretty common. I don't know what the gas bills were like, but it wasn't high enough apparently to buy a setback thermostat even though apparently gas more than doubled. I do remember there was no snow around the house. WE were one of the last in the neighborhood with the original heat, as most had succumbed to the concrete affecting the copper pipes. Long before PEX

The second heatloss number newtonsapple posted sounds more like what I would assume. 2 inches is still pretty standard, but one could argue the merits of more. I do not think that floor heatloss is the source of the OPS issues.
 
Don't forget one of the best ways to insulate and heat a shop: fill it full of equipment and stuff!
A shop full of iron will acts as a slow-loss heat sink for the airspace and the concrete floor.
A lot less airspace to heat. A lot more concrete covered with iron.
For simplicity of install and ability to throw a lot of heat, one of the hanging unit-type natural gas heaters is hard to beat.
Since 2001, we've had a 175k natural gas unit here at the 4,000 sq.ft. shop (14-16' ceilings and basic insulation package), and the heater does a good job at countering our higher-elevation southwest-Virginia winters.
We run the heat on 68 during the day and 60 at night, with the monthly flat-pay gas bill averaging $150. Although nat. gas has gone up recently, I've yet to see much change on the gas bill...yet.
An overhead ceiling fan diffuses the warm air nicely.
So, with a building full of equipment and efficient heat, you can get by with a basic-insulation package.

ToolCat
 
If I update the HDD to cover the Oct. 17th - Nov 19th I get 809. With an annual 5570 HDD, that works out to 4634 gallon or $11,121. It would be interesting to know how that compares to the gallons used last year.

Using the updated numbers, heat loss for the building is 3172 BTU/H/Deg.

199,000 BTU/H / 3172 BTU/H/Deg = 62.7F delta to run out of capacity.

Coeur D'Alene Airport is used as the location for Bonner and has a 99% design temp of +10F. No capacity issues if that is true. OP has been through one winter, so they can let us know if they ever weren't able to maintain the 60F setpoint. Someone more knowledge of the local area could likely pick a better reference:

This is a load calc using actual fuel use, which is generally accurate at predicting total fuel use. It will also provide an accurate capacity estimate without the overestimate seen from of sq ft * DT/ R.

If I assume the enclosure is performing at the table listed total wall R Value of 7.2 and using the updated floor load, I get that you would need about 900cfm of infiltration to match the fuel usage based actual BTU consumption. That is a LOT, but not unheard of. But ton of infiltration along with some missing insulation in areas like a stem wall would do it. Increasing the total wall R value will result in significant savings, particularly because the smart approaches will also address infiltration. The focus on total wall is super important, 4x insulation in the bays will barely move the needle.

It is still worth checking for weird things like leaks in the loops. I would also review where the moisture barrier was placed relative to the sub slab foam. If they happened to place it below the foam, the slab can be sitting in a bathtub. Putting the plastic below the foam makes it seem like the foam will stay dry, but it instead it traps water in the foam.

Regardless of any calculation details, it is clear this building is pissing away fuel. We aren't going to fix this here though other than to push that they need someone who can analyze the situation on site. There are just too many things to cover. A blower door will give the real infiltration load, identify the major leak sources, and spot major thermal issues.

I believe code compliance still may be required where the OP is, even if there are no inspection. It is the builder's responsibility to ensure code compliance (at least where I am), so there might be some avenue for legal action. I would imagine the builder would only be responsible for the additional remediation costs beyond what it would have cost to build it right the first time, so it may not be cost effective.
900CFM, or a big blower running 24/7
RE: r7.2 Looking at the chart, I think it is for a standard stud wall with steel studs. I think this is not the case if this is a standard industrial building I am familiar with. Basically no studs at all, but with the insulation pinched between the purlins . Far more continuous than a stud wall. OF course we have no pics. I have been calculating using high r values.
Design temp, I do not believe a place where it averaged 34 degrees for the month of November has a design temp high than Eastern Mass, and guess what, the weather station for that county is significantly south and on a lake. I was assuming about Zero, which I think is correct for the OPs actual location. IOW, it is going to be 9 degrees tomorrow night, not even December yet, I think 0 is a better design temp.
Remember that HDD is an average, and we live through the peaks not the average. Now it may not matter if the building loses temp when it is the middle of the night, but certainly not ideal.

I still think he has a gaping hole in the roof.
Perhaps an unshuttered welding hood, or the contractor did not seal the joint where the building meets the foundation. It would be hard to believe the OP leaves an overhead open by a foot all day and night and didn't bother to mention it. From a quick perusal, that is about what 900 CFM would look llike
 
Actually it doesn't really do that. First, everything is an insulator to some extent, some are just good enough we call them insulators. So soil is to some extent, an insulator. Running water under the slab would be problematic, but the soil underneath does indeed get warm and stay warm, unlike outside air.
I love radiant heat, I grew up with it. Uninsulated slabs in little ranches were pretty common. I don't know what the gas bills were like, but it wasn't high enough apparently to buy a setback thermostat even though apparently gas more than doubled. I do remember there was no snow around the house. WE were one of the last in the neighborhood with the original heat, as most had succumbed to the concrete affecting the copper pipes. Long before PEX

The second heatloss number newtonsapple posted sounds more like what I would assume. 2 inches is still pretty standard, but one could argue the merits of more. I do not think that floor heatloss is the source of the OPS issues.

Heat loss calcs through slabs are based on real worlds studies I believe to bake in the dynamic nature of the soil insulation. There are a bunch of different models, some factor in soil type and moisture.

The basic calc is based on ft of perimeter as the perimeter dominates the loss.

Delta Temp * F-Factor * Ft Perimeter = BTU Loss through slab

This is the ASHRAE table, I think manual J uses a similar but slightly different approach. I am not a pro at this, but I run these sort of calcs every few years for a project. It is usually a cleanroom where we only care about cooling.

1669562728016.png

Many basic to be reviewed onsite for the OP. I've seen plenty of R23 insulated garages with uninsulated 3ft curb walls that pretty much defeat all the insulation above.
 
900CFM, or a big blower running 24/7
RE: r7.2 Looking at the chart, I think it is for a standard stud wall with steel studs. I think this is not the case if this is a standard industrial building I am familiar with. Basically no studs at all, but with the insulation pinched between the purlins . Far more continuous than a stud wall. OF course we have no pics. I have been calculating using high r values.
Design temp, I do not believe a place where it averaged 34 degrees for the month of November has a design temp high than Eastern Mass, and guess what, the weather station for that county is significantly south and on a lake. I was assuming about Zero, which I think is correct for the OPs actual location. IOW, it is going to be 9 degrees tomorrow night, not even December yet, I think 0 is a better design temp.
Remember that HDD is an average, and we live through the peaks not the average. Now it may not matter if the building loses temp when it is the middle of the night, but certainly not ideal.

I still think he has a gaping hole in the roof.
Perhaps an unshuttered welding hood, or the contractor did not seal the joint where the building meets the foundation. It would be hard to believe the OP leaves an overhead open by a foot all day and night and didn't bother to mention it. From a quick perusal, that is about what 900 CFM would look llike
That 10deg design temp does seem warm. They have capacity down to -3F, and your can almost always swing short term dips well below your design capacity. Not the end of the world if the place dips to 50F for a bit either. The warm slab should protect any plumbing. There is a decent cost hit pushing above 200K BTU/H, so that seems like a good choice. If it gets chilly, just get some machine spindles turning.

I haven't really dug, but I haven't seen a total wall R value calculation for a steel building. I think the purlins are usually hat channel that would flatten 2.5-3.5" of insulation, so more than a standard steel stud. OP also mention pulling the insulation tight. On the other hand, the 22% framing fraction on that table is likely high as this place has likely big straight walls. I bet there is still a bunch of steel conduction a lot of heat that needs to get covered.

There very well could be a big exhaust, HRV, or ERV going to keep the shop air clear. Fresh air is important in most shops, you just need to plan for it and understand when it makes sense to have heat exchangers. I can also imagine some big leaks at the intersection of the wall and roof if some thought isn't put into the detailing there.

Definitely curious to know what the total fuel usage was last year.
 
Not quite sure how to read that graph. Looks like they are saying R5 is next to useless, I would think that odd.
The first 'R' is the most important
I find many numbers act like a concrete wall acts like a tent wall, but it practice it does not. I have long assumed the difference is the mass effect, meaning the heating plant only fights the average temperature, not the max.
re: framing fraction, I think the purlins are likely 4 ish feet apart.
 
Don't forget one of the best ways to insulate and heat a shop: fill it full of equipment and stuff!
A shop full of iron will acts as a slow-loss heat sink for the airspace and the concrete floor.
A lot less airspace to heat. A lot more concrete covered with iron.
For simplicity of install and ability to throw a lot of heat, one of the hanging unit-type natural gas heaters is hard to beat.
Since 2001, we've had a 175k natural gas unit here at the 4,000 sq.ft. shop (14-16' ceilings and basic insulation package), and the heater does a good job at countering our higher-elevation southwest-Virginia winters.
We run the heat on 68 during the day and 60 at night, with the monthly flat-pay gas bill averaging $150. Although nat. gas has gone up recently, I've yet to see much change on the gas bill...yet.
An overhead ceiling fan diffuses the warm air nicely.
So, with a building full of equipment and efficient heat, you can get by with a basic-insulation package.

ToolCat
be interesting as a reference point if you would look up what you paid for gas last, would allow a apples to apples ish comparison
 
Not quite sure how to read that graph. Looks like they are saying R5 is next to useless, I would think that odd.
The first 'R' is the most important
I find many numbers act like a concrete wall acts like a tent wall, but it practice it does not. I have long assumed the difference is the mass effect, meaning the heating plant only fights the average temperature, not the max.
re: framing fraction, I think the purlins are likely 4 ish feet apart.

I was only looking at the F-Factors for the "Fully Insulated Slab" lines. Going from no insulation to R5 is F1.35 to F.74, so roughly half the heat loss. The other two sections with limited perimeter insulation are probably two different design details. I don't have the standard and this image might be missing something on the left.
1669568930895.png

OP said purlins were 24" OC in the first few posts.
 
What did you do about vapor barrier in your floor because XPS is not enough and you cannot tape it well enough. The best floor style is plastic vapor barrier, XPS, pex (fiber or rebar) and then your concrete. If you just slapped foam down you will see a loss. Tape will help a little but plastic under foam is king.Also cracks in the above insulation are onr with but not spraying over I beams means they are pulling in cold cold air. You can see this and eve with wood posts you can see heat transfer without a barrier between post and tin. Just something to add
 
With 14 ft. side walls and a 21 ft. peak you are heating way more cubic feet than you are actually using. Anything you can do to bring down the ceiling height in certain areas will help. Wall off some areas and hanging a drop ceiling or even stretching a blue tarp will hold heat down to the peopled area.
 
If I update the HDD to cover the Oct. 17th - Nov 19th I get 809. With an annual 5570 HDD, that works out to 4634 gallon or $11,121. It would be interesting to know how that compares to the gallons used last year.

Using the updated numbers, heat loss for the building is 3172 BTU/H/Deg.

199,000 BTU/H / 3172 BTU/H/Deg = 62.7F delta to run out of capacity.

Coeur D'Alene Airport is used as the location for Bonner and has a 99% design temp of +10F. No capacity issues if that is true. OP has been through one winter, so they can let us know if they ever weren't able to maintain the 60F setpoint. Someone more knowledge of the local area could likely pick a better reference:

This is a load calc using actual fuel use, which is generally accurate at predicting total fuel use. It will also provide an accurate capacity estimate without the overestimate seen from of sq ft * DT/ R.

If I assume the enclosure is performing at the table listed total wall R Value of 7.2 and using the updated floor load, I get that you would need about 900cfm of infiltration to match the fuel usage based actual BTU consumption. That is a LOT, but not unheard of. But ton of infiltration along with some missing insulation in areas like a stem wall would do it. Increasing the total wall R value will result in significant savings, particularly because the smart approaches will also address infiltration. The focus on total wall is super important, 4x insulation in the bays will barely move the needle.

It is still worth checking for weird things like leaks in the loops. I would also review where the moisture barrier was placed relative to the sub slab foam. If they happened to place it below the foam, the slab can be sitting in a bathtub. Putting the plastic below the foam makes it seem like the foam will stay dry, but it instead it traps water in the foam.

Regardless of any calculation details, it is clear this building is pissing away fuel. We aren't going to fix this here though other than to push that they need someone who can analyze the situation on site. There are just too many things to cover. A blower door will give the real infiltration load, identify the major leak sources, and spot major thermal issues.

I believe code compliance still may be required where the OP is, even if there are no inspection. It is the builder's responsibility to ensure code compliance (at least where I am), so there might be some avenue for legal action. I would imagine the builder would only be responsible for the additional remediation costs beyond what it would have cost to build it right the first time, so it may not be cost effective.

" If I update the HDD to cover the Oct. 17th - Nov 19th I get 809. With an annual 5570 HDD, that works out to 4634 gallon or $11,121. It would be interesting to know how that compares to the gallons used last year."

Last year I spent $10K and change, but took the month of Dec off so was not heating the shop above 50 deg for that month I was gone.

There are not any likely leaks in the loops as the FTVN boiler is a pressurized system and I have not has any pressure drop in over a year. When it was installed I was told I may have some in the first couple months as there can be small pockets of air trapped or entrained in the water that are removed by the air purge valve. There is a 2 Gallon (aprox) surge tank in the system that maintains pressure. I added about a quart of water to the system a year ago to make up for any bubbles that came out.

Hydronic loops are stapled to the foam. Poly sheeting went under the crete as a moisture barrier, but is is on top of a raised pad of 80 yards of crushed limestone and 4" of sand that was compacted with a real deal big ass roller compactor. Floor is 6" thick ,6000 PSI crete. Shop sits about 20" higher than surrounding grade, we did this due to the fact we are on a bench on the side of a mountain and spring breakup sends a good deal of water down the mountain.

As far as builder liability, I was the "builder" - I had the slab and hydronics done, but my family and I put up the pre-engineered building from a kit. We have a crane and necessary equipment to assemble.

As far as your calculated air infiltration, that is tough to believe if could be that high😮 - As stated above the 2 overheads are high end doors and the only spot I think I could have a air leak would be at the tops of the doors. The Insulation blanket, as poor as it is/was is all joint taped continiously so there should be an air barrier throughout. There are 2) 36" man doors that are Jeld-Wen standard flush steel doors from HD and there are 3) 36"x48" Jeld-Wen Low-E glass sliders about 2' down from the eve along the west side for ambient light. (and to let me know when it's time to go home)

Any other thoughts are appreciated.
 








 
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