Insulating gap on lean-to greenhouse wall
Limited by space and site options my new lean-to greenhouse is fitted with a base on decking.
The way the decking was fitted in this new house means with the greenhouse flush at the top to the wall, one side wall has a 1" gap. This is great for ventilation now, but in winter it is really going to cause a lot of problems.
What has anyone used to seal an 8 foot x 1 inch gap? Could I use something used in lofts? Should I get a piece of wood cut and have it slotted in (the frame of the lean to is aluminium so hammering isn't an option).
Any tips or ideas would be really welcome. Thanks in advance.