Floor Joists and Subfloor Complete

We have now left the concrete stage and entered into the wood stage. Exciting, yes! We're almost there... right! The first thing we did after filling the forms with concrete and attaching the post bases was to cover the area with thick plastic. We cut holes in the plastic for the holes and made everything fit pretty snug. This plastic will create a vapor barrier and hopefully prevent any moisture from affecting the floor system.

At first we were going to use 4x4 pressure treated wood as beams, but after realizing we really wanted a bit more height we decided to go with two 2x8s instead - thereby creating a 4x8 beam. It was cheaper and easier to find pressure treated 2x8s so we bolted the boards together to attach them. All in all we needed to create four "4x8s" to rest on the post bases.

We also picked up these steel plates to rest on the post bases to move the beams off the concrete.

Here we're laying our boards down on the post bases. (Yay, they fit! We would have gone absolutely crazy if they didn't!)

Through the boards we drilled and placed long bolts, we also put nails in (specifically made for going into pressure treated wood) to secure everything.

After securing all the pressure treated boards, we just had to put up all the fir boards to see what it would look like once they were all attached!

Trying the new beams out with puppy!

The next day, we got to work putting together the floor joists. We used liquid nails specifically made for exterior subfloors and decking, before nailing the wood together.

Building the frame on top of the pressure treated wood beams.

Making progress...

All around the sides we decided to double up on the boards to create a sturdier frame. By doubling up the frame around, we created a three inch wide frame. This will come in handy later on when building walls, since we will use 2x4s to frame them and then you can nail down into the floor without issues.

We used construction adhesive again to glue the boards together before nailing them in.

I got some left-handed comments on my hammering style! Apparently the two-handed-hammering-style is not the preferred way of hammering nails in, or so I've been told! But hammering these 16d nails in is hard! I prefer smaller nails, or else I'm using both hands...

And here is the main frame. It measures 16 inch on center for all the floor joists. We have put in blocking here to provide more support so no span is greater than 5 feet or so.

Hurricane ties were used to tie the joists to the pressure treated base. We made sure to use the right nails - special nails for pressure treated wood went into the bottom, and regular nails went into the floor joists.

And finally, we were ready to attach floor boards on top of the joists!

Again, construction adhesive (liquid nails) went down first on all the floor joists and then we put ¾ inch Tounge and Groove OSB (oriented strand board) down on top. Next we put down a chaulk line to see where the floor joists go underneath and started nailing.

In terms of nails, we used 8d ring shank nails which means they are more secure in the wood than smooth finish common nails.

And there you have it. The foundation, joists and subfloor down. And hot days to work in! But, we're not complaining, we're making progress! 

Next up: building walls!