I would like to fill in the space between the ground and the cottage so I can keep the cold out. Whats the best way?
Not enough information. I will assume its on blocks/piers. I know this is a real pain but you should insulate the floor and cover it with 1/4" plywood or better yet tin, to keep the critters out. Or spray 2lb foam in the floor cavity no plywood (expensive). Or, the other way is to simply frame it with PT 2 by 4s on 24" or 48" . Add 2" xps rigid foam over the framing, and cover with PT plywood or vinyl siding outside, Much less painful except for the pocket book, and doesn't work very well unless you semi heat the space and insulate the ground .
The previous post is correct. More information is required in order to provide you with better information. If the space is enclosed, there are a number of additional issues to deal with ie moisture management, air circulation, etc. If it is open as previously suggested, then spray foam, while more costly, is perhaps the most effective option.
Kingsway Construction Inc
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