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Volume 7 Issue 2“Building Confidence”February 2009



Welcome to the building newsletter which gives you confidence so you can do it yourself. Spring is just around the corner so get those projects ready for the good weather.

Ask Away!

These are the questions that I answered this month.

Hi Dave, I have a plumbing question. Project is new home construction,
slab on grade, single story. I have 4" pipe stubbed out for toilets.
Toilet flanges are glue in with about 1/4" thick stainless ring on
top. Do they install on slab or finished tile floor?

Hi Neal,

Funny you should ask that question. I just finished hooking my toilet up to a 4" stub out on a slab on grade. Sounds like you have quite a fancy floor flange there with the S/S ring. I'm assuming you are connecting to a 4" ABS pipe. Anyway, yes the flange goes on top of the tile floor. BUT, checkout the flange you have, it should say 4"x3" on the top of it and should fit inside the pipe. Try it for size in the pipe, before installing the tile. Now, be aware: if the flange is a "flush" flange it will go tight to the top of the pipe, if the pipe is cut off flush with the tile. If the flange is standard for a wooden sub-floor it may have a cove built up of plastic on the outside of the spigot directly under the flange itself which will prevent the flange from going tight to the top of the pipe. If this is the case, you need to either return the fancy flange you have for a flush flange or cut the pipe off just below the concrete. The cove prevents the flange from going to the top of the pipe by about 1/2". If the tile is 1/2" thick (which I doubt, usually about 3/8" with thinset) the pipe can be cut off later, flush with the tile. If not the pipe should be cut off just below the surface of the concrete.

This is what happened to me. I installed the tile around the pipe, pretty as you please. Then discovered the floor flange did not go down to the tile, but was held up about 1/2". Rather than run to the store and buy a flush flange, I found a worn down (about 3" diameter) cut off disc for metal for my 4 1/2" angle grinder. I removed the guard and cut from the inside of the pipe about 1/2" below the top of concrete. Actually burned my way through. It was very easy, but smelled up the place - lucky I had the bath fan installed. Just a heads up, I thought I would mention.

Also, remember to remove the test plug, if so provided in the flange, before mounting the toilet.

Also, spend an extra buck and install a wax ring with built in flange or collar rather than the straight wax ring.

Thanks for the question, a good one.


I love getting emails like this:

HI. I am a homeschooling mom of an 11 year old boy. Your website has
helped me put together Q&A for my son to supplement his shop class
with his grandpa. I just wanted to thank you for putting in the work
to make this site. It is appreciated.
Holiday, FL

Thanks, Lisa, Dan and I appreciate your email and taking the time to send it.

My eldest daughter homeschools her 3 kids (10 to 13) and I am the grandpa (Papa) that shows them stuff in the shop, so your email is familiar to me. Anytime your son's grandpa needs to ask me a question or clarify something, have him email me for a prompt reply.

I hope you get our Newsletter!

Thanks, again,

Dave and Dan

I didn't sign up for the newsletter. Can you add me?
What a great story. I will pass it along to my father-in-law.
Thanks for your work. I'm sure there are others out there using
your website that just don't take the time to let you know.
~ Lisa

Okay, Lisa, you are subscribed to our Newsletter. You will be informed when the next Newsletter is on our site with a link to go there directly. Here is a link to that same page where you can view all our Newsletters or the last one.

Another thing I should mention is that on the top left of every page is a little search box. You can type in keywords in this box and click Search to find these words if used on our site anywhere. It is like a personal search engine for

By the way, we have a free policy for apprentices or students of construction here on our site. If they are interested in viewing plans on our site, we give them free access. If your son is interested in studying plans, just let me know. The starving student syndrome - I've been there before...

Thanks for the interest in our site,


Hello, Dave
My Question: How can I FLATTEN not LEVEL my WAVY kitchen floor to
prepare it for a "DuraCeramic" (Vinyl Tile) finish floor? So that the
bumps and tapers don't show up everywhere.
THE DATA: 3/4" T&G OSB (not enough glue or nails used) over undersized
2x10 spruce joists, should be x12's (springy but save question for
another day).
The Joists were poor quality and didn't make any difference to the
builder if they were crowned up and down randomly. The rise and drop
of the floor varies between 3/8" to 1/2" in 3 to 4 feet, in both directions,
and consecutively (up, down, up, down). Subsequently, I have sheet vinyl
over a 1/4" Ulan sub floor now. Do I tear both up and start over or just go
over what I have?
P.S. There are also numerous squeaks cause of gaps in the little to no
construction glue and lack of adequate nailing!
I was thinking of using 3" coarse a/p screws to stop squeaks.
THANKS for any help you can muster,
Having OCEANS OF FUN in Pennsylvania,
Dave M

Hi Dave,

It sounds like a real mess there. I would pull up the 1/4" Ulan and start from the subfloor. Make sure the end joints on the OSB have 1/8" clearance between sheets. If not, set your saw to depth and cut new expansion joints there. OSB needs room to expand and contract. If the underside is exposed go down there, using a latex with silicone caulking such as Alex Plus, and caulk up between the bottom of the OSB and the top of the joist, if there any gaps that you can see. Right after the caulking go back upstairs and screw the OSB down with 2 1/4" deck screws to compress the caulking before it dries. Deck screws have a coarse thread and are bought in bulk, so are a lot cheaper than buying boxes of 100. Just get the plated deck screws, no need for the fancy galvanized or stainless variety.

Now you should have a firm squeak-free base to work from. You will probably notice the floor not as bouncy, as well. Okay, try to level the floor out if possible while you make it a flat surface by ripping 1/8 to 1/2 inch x 1 1/2" strips. Just tack these strips in place with a bit of subfloor adhesive under them as well. Place these strips directly over the joists. For hollows less than 1/8" apply a 1/4" bead of construction subfloor adhesive to the OSB, just before installing 5/8" standard T&G plywood. As you install each sheet screw them down right away with 3" deck screws, as before. Place the screws at 6" along the edge and 12" in the center of the sheets. Keep the screws back about 6" from the tongue until the next sheet is installed.

I know this is a lot of work, but you can't fix something like this by adding on to the problem, you need to get to the source.

I'd be interested to know what the span is for those floor joists and their centers. Also, if below them is crawlspace or finished ceiling and if unfinished is there bridging and strapping in place?


I want to install a ceramic toilet paper holder in a drywall.
I am not sure how I should make the bond between the wall and the toilet
paper fixture.
I did a Google search and it brought me to your website but I couldn't
find any information.
Please advise.

Hi Al,

Ceramic holders are designed to be glued with silicon seal onto ceramic tile. If you want to fasten it to drywall make sure the drywall is primed and painted, then lightly sand the area of surface contact on the drywall. Tape the holder into position until set and don't put any weight on it for 24 hours.


Well, that's it for this month. I hope what you have read here may be able to help give answers to your project.


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