# Drywall: 1/4" gap near the floor?



## girlitomboy

Is there a specific reason I am supposed to leave a 1/4 " gap on the bottom when hanging drywall?
I haven't got an answer other than "that's what I was always told to do but I couldn't tell ya why".  
That is why I am here because there's nothing about it in the DIY "bible" I bought and I haven't found any information online other than "oops" cover-ups.
Another question. Which should I do first: the drywall or the floor? I wouldn't think it would make a difference, but that's why I'm asking since I don't know for sure.
Thank you!!


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## Maintenance 6

If there is any settling or shrinkage in the framing, the 1/4" gap absorbs it without crumbling the drywall. Some places leave 1/2" so that water from floor scrubbing can't contact the drywall and wick into it.


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## tcleve4911

The gap on the bottom of sheetrock is to allow room for a prybar or lifting tool to lift the panel up to the ceiling (if hung vertical) or to the upper sheet (if horizontal).
Sheetrock is hung tight to the ceiling with a gap at the floor.


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## 95025

girlitomboy said:


> Another question. Which should I do first: the drywall or the floor? I wouldn't think it would make a difference, but that's why I'm asking since I don't know for sure.
> Thank you!!


The other guys answered about the drywall...

What kind of floor are we talking? As a rule, your floor should be the last thing to be installed - and for several reasons.


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## stradt03

I hung mine 1/2" from the floor in my basement to avoid any moisture pickup. I had a strip of scrap Sheetrock that I set the piece I was hanging on while I secured it to the wall.


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## girlitomboy

It is a glueless interlocking hardwood floor that has a rubber backing, is "100% waterproof", "ideal for kitchens, bathrooms, and basements", "anti-bacterial", "sound absorbant", and ""requires no underlayment". At least that is what the box says but it is a "New" product that Menards carries so the clerk couldn't tell me much about it.


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## oldhouseguy

girlitomboy said:


> It is a glueless interlocking hardwood floor that has a rubber backing, is "100% waterproof", "ideal for kitchens, bathrooms, and basements", "anti-bacterial", "sound absorbant", and ""requires no underlayment". At least that is what the box says but it is a "New" product that Menards carries so the clerk couldn't tell me much about it.


Do you have a brand name of it? A picture from the box?

I will be curious to know how this works.


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## woodworkbykirk

i do it for two reasons, first being so water doesnt wick up into it if theres ever a leak.. the other being to allow wood flooring a space to expand into as humidity changes


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## girlitomboy

Aquarius Flooring by Maple Leaf Lamisol. Each box covers approximately 18 sq ft.


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## Willie T

The actual reason for the 1/4" at the bottom (in truth it is 3/8" in a perfect world) is very simply to allow for typical variances in the measurements between the floor and the ceiling. Floors are never perfectly flat. This little bit of space allows you room to fit the sheet in.

But there is a problem with this that may catch you unawares.

Precut studs that most homeowners buy at Home Depot or Lowe's are sold cut to a length of 92 5/8". This is not long enough for single top plate walls.

Follow with me: Your drywall is 8'... 96". So your wall has to be taller than that. But, when you nail together a 92 5/8" stud and a top plate of 1 1/2" and a bottom plate of 1 1/2", what do you get? That's right, 95 5/8". Too short.

So you have to plan for a second top plate to go on the wall. And, actually this is proper. A doubled top plate now gives you a 97 1/8" tall wall.

You only have to put 96" of drywall on that 97 1/8" wall. This leaves an inch and an eighth left over. Have you screwed up?

Nope.

The reason is that your wall boards are supposed to be installed AFTER the ceiling boards have been hung. They actually support all the perimeter of the ceiling boards because you do NOT fasten the ceiling boards in the areas up close to the walls. You leave at least a foot of the edges of all your ceiling boards "floating" (unfastened), and slightly drooping.

There are a couple of big and important reasons for doing that..... but we are just discussing wall height right now.

So, you are going to support the previously installed 5/8" ceiling board with the wall boards. That further reduces your wall height to 96 1/2". Now you have a 1/2" gap.

But you are going to find that when you lift the top horizontal board (the only way to hang drywall correctly), not all of the ceiling boards will be right on the same plane. Some will be a little higher than others, some will be lower. It is this top horizontal board that levels out that variancy to help create a visually perfect and virtually straight ceiling-to-wall intersection up there. This is how you keep your edge up there from looking like it is undulating up and down like a roller coaster.

By the time that the top boards are hung on the wall, they will almost magically give you room for that necessary gap at the bottom..... which will be *about* a quarter of an inch.

And that gap is important for helping you hang the bottom board.

You can buy a TOE Jack like the one pictured below (about 16-17 bucks) to jamb under the bottom boards as they sit on the floor. This makes it SO easy to lift the bottom boards with your strong leg muscles so that you can easily get a tight fit between boards.

So, now you have it in a more complete version. Yes, you need that gap.


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## woodworkbykirk

ok again in 5000 words less.. 

as for the panel llfter.. a flat bar will do it as well and is is $16 cheaper


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## chrisBC

Do the floor after the walls-This way you can mud, sand, and paint the walls, and not have to worry about scratching/having to clean your brand new flooring.


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## 95025

Willie T said:


> The actual reason for the 1/4" at the bottom... Yes, you need that gap.


Danged math people! :laughing:


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## Willie T

DrHicks said:


> Danged math people! :laughing:


Well, I would have gone that short and sweet route, but from the OP's question it looked like we just might have a thinker here, and I figured she probably really wanted to know some reasons for leaving that gap. :yes:

One day a good friend of mine, Harry invited me over for dinner. It was “pot roast night” and he had been raving about his wife’s secret family recipe and how I would have never tasted a roast so good.

Sure enough, as expected, dinner was nothing less than spectacular. But I did notice something peculiar.

As the roast was being served on the table and the pot was being opened, I noticed that the roast had been cooked with its ends cut off… Being naïve, I asked the question, “Why are the ends cut off the roast like that?” The answer I got was “I’m not sure, that’s the way my mother used to cook it.” With no further explanation, I enjoyed stuffing my face on this spectacular feast. Harry was right, the roast dinner was absolutely brilliant!

A few weeks later, Harry came rushing into my office with a look of excitement on his face. He blurted out, “I must tell you the story of the pot roast….”

Last week my wife had her family reunion, and while we were chatting, the question of the famous pot roast came to my mind. I asked Mary’s mother, “Why do you cut the ends of your pot roast that way before you cook it?” She answered, “I’m not really sure, that’s the way my mother taught me to do it.”

Luckily the whole family was there and grandma was busy entertaining the grandchildren with stories of the good old days. I finally had a chance to get her attention and ask about the famous family recipe for the pot roast. She started to giggle, which turned into a belly laugh as I told her how her famous recipe had been handed down through the generations and no one was really sure how cutting the ends off the roast made it taste so good.

She looked me straight in the eye and said, “Harry, this is the funniest story I have ever heard….I’m glad to hear that my recipe has had such a great response, but the only reason that I used to cut the ends of my roast, was because I didn’t have a pot big enough to fit it in…” “I burst out into fits of laughter with her as she really made my day” said Harry.

But then I started to realize that as stupid as that sounded, I was doing the exact same thing in my business. Doing things the old traditional ways because the old tradesman used to say “that’s the way we’ve always done it…that’s when I realized that it wasn’t only me or my wife that had fallen for this trap, but almost everyone I knew had done this to some level…”

How many times in your life have you done things “the way they have always been done?” Only to realize that there is no real reasoning behind it…. This is by far the most common cause of frustration and lack of progress in both our personal and business lives.

(ok, Kirk, not counting this sentence, this was only 547 words.)


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## 95025

Willie T said:


> Well, I would have gone that short and sweet route, but from the OP's question it looked like we just might have a thinker here, and I figured she probably really wanted to know some reasons for leaving that gap. :yes:


A thinker? Here?? Shut! Up! :laughing:

Actually, your explanation was perfect. Thanks.


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## Willie T

DrHicks said:


> A thinker? Here?? Shut! Up! :laughing:
> 
> Actually, your explanation was perfect. Thanks.


Stranger things have happened.


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## AlmondJoy

Hi there, 
New to this forum and excited to be here!
I can say from our ongoing project that you should definitely do the floors last! We laid a really expensive tile floor first thing after demo (my contractor Sister in law nearly had a heart attack, and now I know why). We have spent probably double time on every project looking after the floor- covering it up, sweeping, keeping tools from falling on it, and trying to keep it clean. Thank goodness we haven't grouted yet- the drywall has been a mess, and we still have primer and paint to go. It has been a lesson learned the hard way- next time, the floor will be the last project. Good luck!


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## Willie T

Also, don't make the mistake of putting the cabinets in before the floor.


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## girlitomboy

Yeah, I'm a thinker. Lol! I had planned on leaving the gap, so my new question is how do I lay the different layers of flooring and make sure that gap is there? Just cut the drywall to 7'8" since the walls are 8', hang it snug against the ceiling, and lay the floor under it when the process is done? 
I like to know full details about things because I live in the middle of nowhere and I can't get anyone who knows what they're doing to come help me. Which is why I'm so HAPPY to have found this website!!


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## Willie T

girlitomboy said:


> Yeah, I'm a thinker. Lol! I had planned on leaving the gap, so my new question is how do I lay the different layers of flooring and make sure that gap is there? Just cut the drywall to 7'8" since the walls are 8', hang it snug against the ceiling, and lay the floor under it when the process is done?
> I like to know full details about things because I live in the middle of nowhere and I can't get anyone who knows what they're doing to come help me. Which is why I'm so HAPPY to have found this website!!


You going to have baseboards?


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## girlitomboy

I managed to save most of the woodwork so the plan is to put the original base boards back.


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## Willie T

girlitomboy said:


> I managed to save most of the woodwork so the plan is to put the original base boards back.


You can hold the subflooring cuts as much as an inch back away from the drywall (assuming it ran all the way down), and you only need to hold the actual finished flooring a quarter of an inch or so back. The baseboard will easily cover that. Flooring isn't going to shrink, it only expands, so it will always be under the baseboard.


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## girlitomboy

I know it was previously stated that horizonally is the proper way to hang drywall, but I'm flying solo on this project. Any suggestions?


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## Willie T

girlitomboy said:


> I know it was previously stated that horizonally is the proper way to hang drywall, but I'm flying solo on this project. Any suggestions?


 Yes..... http://www.diychatroom.com/f101/hang-drywall-vertical-horizontal-91458/index2/#post613616

And look around at the rest of the thread too.


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## girlitomboy

Thank you for the reminder. I appreciate it.


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## Ron6519

girlitomboy said:


> Is there a specific reason I am supposed to leave a 1/4 " gap on the bottom when hanging drywall?
> I haven't got an answer other than "that's what I was always told to do but I couldn't tell ya why".
> That is why I am here because there's nothing about it in the DIY "bible" I bought and I haven't found any information online other than "oops" cover-ups.
> Another question. Which should I do first: the drywall or the floor? I wouldn't think it would make a difference, but that's why I'm asking since I don't know for sure.
> Thank you!!


I keep it off the floor in case of water issues. I will leave it off the floor 3/4",except in the basement, then at least 1".


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## Gary in WA

In a basement, be sure to air-seal the drywall keeping indoor moisture from condensing on the cold concrete/block wall with rigid foam board. ADA--- http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach/

http://www.buildingscience.com/documents/reports/rr-0202-basement-insulation-systems

Use a poly sill sealer under the bottom p.t. plate for a thermal/air/capillary break from the cold slab/earth.

Gary


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