It would be good if people said which R-value they were using when working out insulation. There are two different units (ft^2 F hr/BTU and m^2 K/W) and they are close enough that determining which is being used is tricky. I say this because Ohiojay said that foil coating gives an extra 2, but this seems like a m^2 K/W R-value (I've seen values for foil alone ranging from 1 to 2 m^2 K/W), rather than around 10 ft^2 F hr/BTU. (And I assumed that someone in Ohio probably uses ft^2 F hr/BTU) Regarding sealing it up, I'd just use duct tape :) The idea is a good one and I think you're on to something, a further extension of the this would be to permanently mount thin, high-R-value panels at such an angle that they block none of the light in mid-winter, but progressively block more into summer. If you then used very thin plastic sheeting to stop convection (I'd use cheap plastic drop sheet) you would probably double you GH R-value. Here is a link that might be useful: Understanding R-values

I'm here in the Finger Lakes Region of NYS and am getting ready for my first HFGH (10x12)spring. Have an LP heater in and have just received my shipment of bubble wrap from Charley's. My plan was to put the bubble wrap up in a horizontal plane beginning at the left of the door frame and go all around the inside of the greenhouse to the right door frame. I have my shelving hanging off of the wall studs so I thought that this would be easier and neater. The other option is to put it up in the vertical plane. I have the hangers from Charley's, but for the life of me, I cannot make sense of the corner hangers for this bubble wrap. Any ideas, comments and/or pictures of bubble wrap installation would be appreciated. Thanks in advance. Joe Here is a link that might be useful: My HFGH ready for spring

In the attic under the roof, foam seal all gaps at the tops of interior (and exterior) walls to prevent heated moist inside air from venting into the attic space. Such air leaks promote mold and heat loss plus warms the roof. A warmed roof in snow country is trouble. It causes the snow to melt on the upper part of the roof and then the liquid drains to the unheated overhang and freezes making an ice dam and huge icicles hanging off the rain gutter. The condition can get so bad that it wets the interior of the outside walls. If snow is not a concern, heat losses still is. This leakage also affect the cost of air cooling in summer. Make sure that all vents, kitchen, bathrooms, and laundry vent to the outside or through the roof. Do not vent into the attic. Do not skimp on attic insulation. Use plenty. It has a big effect on both heating and air conditioning. I had my attic insulation increased last fall and during the winter months, I measured a fuel reduction of 13 to 15% based on comparing BTU per degree-day between the past two winters. I am also seeing less electric power used for A/C, but do not have enough data yet to make a proper calculation.

Yes, it appears to be glazed structural terra cotta. In that case, you don't want to anchor anything to the walls as it's a fragile material. So you could use closed-cell spray foam to the desired R Value. Or just an inch or so depending on your climate, followed by fibrous insulation between wood or light steel framing. You might want to have the wall inspected first by a qualified expert as the blocks are usually cited as having a 75-year lifespan.