Putting up a greenhouse for the coming ice age

So, we can never grow tomatoes in Canada unless we have a greenhouse.  I'm using an old Quebec garage from Costco, and putting 6 mil plastic from ammie on top.

Then it is raised on the main poles and I hope it can withstand the winds.  The heavier stuff is twice as expensive.  Everybody needs a greenhouse for the next 20 years, or 300 years, whatever.

ps.  so miserable to handle with plastic with just a puff of wind.  Now I'm stitching on the roof with grommets and cable ties.

All done with the standard white sides and I put in the tomatoes in their containers.  So dang hot in their, I'm leaving the front with loose clear plastic.