rotozuk
New Member
I find myself in need of a solution and I have spent a lot of time looking around at different systems and reading here. If you all might have some good advise, it would be great.
I'm located in the North San Francisco Bay area. Temps are rather mild here. We will have a few nights of 30F in the winter and a week or two of weather touching the 100f range, and a maybe a month or two in the 80 to 90 range.. My last house had no insulation or A/C, I fully insulated it and it did not need A/C after that. I had expected the same with this new place being just 15 minutes away. (The house is good, but this out building sucks!)
The challenge is my warehouse is a cheap metal building, about 1,500 sq ft with 15 foot tall walls. Lots of sun exposure. I have insulated it with 2" foam with an R value of 13.1 (best that would fit into the 2" space), but there is a LOT of thermal bridging from the tubular steel structures the walls are built from. There is a huge roll up door that takes the morning sun. I have stacked some spare foam against the inside of it, and put a 90% shade screen on the outside to keep the sun off it. This has helped.
We just had our first heat wave of 100F temps and all efforts to fight the heat in this building failed. It simply delays the heat by about 1 hour. $6,000 in insulation really didn't buy much. (maybe 10 degree lower than outside at best)
I have a solar system on the main house and it runs some micro inverters and tied to the grid, it is about 6k watts. It produces more than I currently use. Living in California we pay ALOT for energy of any form. My solar contract does pay me for overproduction, but if I add to the system more than 10% production, I lose the payment as they will reclassify the system.
Rather than double down on the insulation and probably still have a poor performing building, I noticed the solar A/C units and this started a spiral of research and confusion.
I have a lot of roofs here and plenty of space to add more solar, but I can't tie them to the grid. So these solar heat pumps are very tempting to me for this reason. My thought is rather simple. Insulating this building is pretty much a lost cause. I think I'd be better off spending the cash on some of these heat pumps and a solar field to power them. I'd be happy if I could hold the summer temps down to 80F, and hopefully semi comfortable in the winter months too. (Winters are more in the 40 to 60f range.)
Basic calcs suggest I'd need 36,000 BTU give or take to make the space comfortable. I don't need house comfortable.
One thought I keep having is to install some of these little 12,000 BTU hybrid units as I like the simple 110 grid supply. Start with a single and see what it will do for the building. Just knocking down the humidity might do the trick. I can always add a second or third unit as we see how things perform.
With this said, not that big a deal to add a 220 circuit to feed a bigger unit.
Other times I'm thinking I'd be better off to invest in something like a larger Panasonic and let it eat into my surplus electrical during the summer months.
This is a very basic steel building. This one had zero insulation when it was built. Just a condensation blanket on the roof. I don't have much budget to chase after this goal. I'd rather save my money to make the next building much better from the start.
Any advice would be great. What would you do in this situation?
I'm located in the North San Francisco Bay area. Temps are rather mild here. We will have a few nights of 30F in the winter and a week or two of weather touching the 100f range, and a maybe a month or two in the 80 to 90 range.. My last house had no insulation or A/C, I fully insulated it and it did not need A/C after that. I had expected the same with this new place being just 15 minutes away. (The house is good, but this out building sucks!)
The challenge is my warehouse is a cheap metal building, about 1,500 sq ft with 15 foot tall walls. Lots of sun exposure. I have insulated it with 2" foam with an R value of 13.1 (best that would fit into the 2" space), but there is a LOT of thermal bridging from the tubular steel structures the walls are built from. There is a huge roll up door that takes the morning sun. I have stacked some spare foam against the inside of it, and put a 90% shade screen on the outside to keep the sun off it. This has helped.
We just had our first heat wave of 100F temps and all efforts to fight the heat in this building failed. It simply delays the heat by about 1 hour. $6,000 in insulation really didn't buy much. (maybe 10 degree lower than outside at best)
I have a solar system on the main house and it runs some micro inverters and tied to the grid, it is about 6k watts. It produces more than I currently use. Living in California we pay ALOT for energy of any form. My solar contract does pay me for overproduction, but if I add to the system more than 10% production, I lose the payment as they will reclassify the system.
Rather than double down on the insulation and probably still have a poor performing building, I noticed the solar A/C units and this started a spiral of research and confusion.
I have a lot of roofs here and plenty of space to add more solar, but I can't tie them to the grid. So these solar heat pumps are very tempting to me for this reason. My thought is rather simple. Insulating this building is pretty much a lost cause. I think I'd be better off spending the cash on some of these heat pumps and a solar field to power them. I'd be happy if I could hold the summer temps down to 80F, and hopefully semi comfortable in the winter months too. (Winters are more in the 40 to 60f range.)
Basic calcs suggest I'd need 36,000 BTU give or take to make the space comfortable. I don't need house comfortable.
One thought I keep having is to install some of these little 12,000 BTU hybrid units as I like the simple 110 grid supply. Start with a single and see what it will do for the building. Just knocking down the humidity might do the trick. I can always add a second or third unit as we see how things perform.
With this said, not that big a deal to add a 220 circuit to feed a bigger unit.
Other times I'm thinking I'd be better off to invest in something like a larger Panasonic and let it eat into my surplus electrical during the summer months.
This is a very basic steel building. This one had zero insulation when it was built. Just a condensation blanket on the roof. I don't have much budget to chase after this goal. I'd rather save my money to make the next building much better from the start.
Any advice would be great. What would you do in this situation?
