Spray insulation foam bottom edge siding?

[anne1]

We have older aluminum siding on our home. Can we spray foam insulation up under the bottom edge of it on one side of the house, to seal that opening without causing moisture problems under the siding or not? We get a lot of cold air coming in along the floor board area on that side and want to help stop that.

[pushkins]

As long as you use the "window and door" foam (blue can), leave a space (6") every so often.
My question would be though.....drafts don't often come via under the siding, especially since you mentioned the draft is coming via the floor boards.
Does your house have a crawlspace ?....if so more likely you need to add more or fix existing floor insulation, it may have fallen out, or not be there at all.

[anne1]

The house has a full basement under it with poured cement walls. We even have batting type insulation along the sill boards in the basement too. This cold draft that comes in along the floor boards is also a problem on the second story floor too though. House is older wood sided house with aluminum siding over it. There is a gap along the lower edge of the siding is why we have guessed that the cold draft originates there.

[anne1]

The draft comes in where the baseboard meets the floor boards - to explain it better.