Step 12: Framing - The Bottom Plate

The bottom plate is the base of all the walls you're about to build. It will be secured to the floor using Tapcon concrete screws, and the studs will be nailed and/or screwed onto it. Since it will be in contact with the concrete floor, it must be pressure treated in case of moisture issues.

When you select the lumber for the bottom plate, make sure it is straight, flat, and without any warps or twists. Before you load each piece onto your cart at Home Depot (or wherever you get your lumber), sight along the length to look for defects. If you spot anything, put it back. To reduce headaches later on in construction, the bottom plate (and the top plate) must be perfect.

*Note: Don't go lumber shopping with a spouse or child. They'll go nuts with boredom as you spend an hour or two sorting through a skid of wood looking for the best pieces. Trust me.


The bottom plate will determine where all of the walls are, so make sure you position the pieces carefully. Place the 2x4s close to the wall, with no more than a 1/4" gap between the wood and the wall/insulation. For long spans requiring more than one piece of wood, make sure that the pieces are parallel. At corners, double check your angles - 90, 45, etc. It pays to take your time here.


Nothing complicated here. Measure twice, cut once with the miter saw. Strive for an easy fit with no gaps between pieces.


Grab the hammer drill and install the masonry bit. The drill should have a gauge on the side, that you can use to control the depth of the hole. In this case, the hole will be the length of the screw plus a bit of margin (say, 1/2" extra). With the bottom plate in place where you want it to be, drill straight through the center of the wood and into the concrete, perpendicular to the floor. Drill the first hole near the end of the piece, about 6" from the end. It may be necessary to pull the drill out a few times, so the concrete dust can escape. It helps to stand on the wood as you're drilling to keep it from moving around.

With the first hole drilled, drive in a Tapcon screw using the power drill. I suggest using a socket head bit to do this, it slips a lot less. Don't drive it all the way in just yet. Again, it helps to stand on the wood so that it stays flat on the ground.

Now, go to the other end of the bottom plate, realign the wood if necessary, and drill a second hole. Drive in another Tapcon. Now the bottom plate won't move, and you can go ahead and drive in a few more screws along the length of the bottom plate. At the very least, place one every two feet or so.

Continue in this manner with the rest of the room. Take extra care when aligning interior dividing walls - they should be perpendicular to the outside walls (unless you have something avant garde planned). In places where a door will be, place the bottom plate right across the gap - that section will be cut out later when the door frame is finished.
Hi..what laser level were you using? I've been looking for one that wont cost a fortune.
Extremely helpful! Hat off to you!
Looks nice! I was wondering how your floor is holding up after a few years. I've been doing some research on waterproofing my basement and I have not seen anyone else use that type of vapor barrier...just other (and much more expensive) options that I am hoping to avoid. Have you had any problems with moisture seeping through or causing problems underneath the flooring?
No moisture or mold issues as far as I can tell. But, we have a relatively dry basement. Before starting on a basement flooring project I'd suggest doing a moisture test - tape a 1 square meter piece of plastic to the floor and let it sit for a week or two. If no water condenses under the plastic in that time, then you're good to go!
Good to know, thanks! I just found out during the inspection that the house I'm buying has already been waterproofed, so at least that part is already taken care of :) Will still do a moisture test regardless.
Most likely, those are spaced like that (the staggered pieces between the studs) as a fire block. This is code in some areas. It prevents, or at the very least slows the spread of fire up the interior of the wall. Homes built without these in an exterior wall may find their attic on fire before they even know there is a fire in the wall.
Think I'd be wearing steel toe cap boots during the demolition. Nails through the instep are not nice....<br />
Agreed.&nbsp; And for most of the renovation, I did!&nbsp; Many of the pictures taken here were, *ahem*, posed a little...&nbsp; ;)<br />
Beautiful work, and a stunningly complete 'ible<br /> Well done. <br /> Steve<br />
Thanks.<br /> <br /> I have plans to do a bathroom this summer.&nbsp; Hopefully I'll find the time to do it!<br />
&nbsp;Did you have to use anything to hold the foamboards in place while the PL300 was curing or are they light enough not to require that? (The user manual that comes with it says you need to use some type of a fastener to keep things under pressure until cured. ) Also, how long did it take in your case to dry?<br /> <br />
Nothing in particular.&nbsp; I stuck the boards down, pulled them off for a minute or two, then stuck them back on as per instructions.&nbsp; After that, they stuck all by themselves quite nicely.&nbsp; The foam boards aren't heavy at all, and PL300 is very, very sticky.<br /> <br /> I'm not sure how long they took to dry.&nbsp; Unused glue squeezed from the tube and left in the open air took about a day to get rock hard.<br />
&nbsp;What would happen if/when adhesive eventually fails? Would &nbsp;you rely on the studs holding the foam and things remaining airtight?
Presumably the adhesive is intended to be permanent.&nbsp; But, in the unlikely event that it does fail, the second layer of insulation pasted on top, plus the tape, plus the studs on top should hold it in place.<br />
I love Roxul too, I'm planning to use it for my basement reno, as well.<br /> but dude, Roxul isn't fiberglass -- it's mineral fiber, so it doens't make you as itchy as fiberglass though.&nbsp; You still need the breathing / eye protection like you describe. :D<br />
Yeah, someone informed me of my mistake on a different step.&nbsp; Whoops!&nbsp; But, it doesn't really matter which you use; either fiberglass or mineral fiber (aka rock wool) will work here.<br />
Have you noticed a significant change in your energy bill from the fiberglass insulation? I'm debating on whether or not it's necessary with the foam panels...I am on a very limited budget...<br />
Hard to say how much more of a difference the fiberglass makes, since it was installed at the same time as the foam.&nbsp; The top of the wall feels *slightly* warmer than the bottom, but that may be because heat rises.<br /> <br /> Think about it this way:&nbsp; a basement renovation is something you're likely to do once.&nbsp; It'll cost a few hundred more to pack in more insulation, but in the long run it's worth doing really well.&nbsp; The foam panels will likely give you your minimum R-value to meet code, but I'm a fan of exceeding code where possible.<br />
amazing instructable!!
Thanks very much for putting this together. It has given me the confidence to attempt this huge task myself.
No problem! Breaking it into smaller parts, taking time to think things through, and asking lots of questions (and asking for help!) will help you get through it. Oh, and one other thing: Don't lose your momentum. Always do something every day, and don't do anything else until it's done. Make sure that everyone else in the household understands this as well.
That is excellent advise! I will definitely follow it. Thanks again! Eric

About This Instructable




Bio: By day, Jeff is the Jack of All Robots at Clearpath Robotics. By night, a mad scientist / hacker / artist / industrial designer wannabe!
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