Never tried LEGO'S to install porch flooring, But I guess there's all types . A flooring nailer would be your best bet, IF you can find a cleat that would be for outside use. I haven't seen any for my Floor Power nailer but I'm sure there is something out there.
What I have done in the past is to pre drill and install stainless steel screws into the tongue. And also we hand nailed the tongue, I have seen this installed with the trim nailer, but would not recommend it as for the nails not being of the correct gauge, and correct holding strength for the floor.
And as for sealing the floor before you install it ,That's the right way to go, especially when your close to the ground. just make sure your porch floor is vented. Hope this helps BOB
I just wanted to say that today our packaged arived from China with the most wonderful set of building toys. My son loves them. It is a pirate building block set, a very large boat. My son says it is called the black pearl from the pirate movie. The parts in the set fit together with his lego brand bricks but this set we bought is not lego brand. What is the difference? Here is the address to the bulding toys http://www.liangdianup.com/buildingblocks_1.htm and the company's main website page is www.lducompany.com
There is no place to post a review on thier website but if there was I would surely give these guys a 5 star