OldTools Archive

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275033 James DuPrie <jbn.duprie@g...> 2022‑01‑03 wood movement and construction question...
I'm moving forward on the library project (year 2 now), and I figured I'd
toss the latest dilemma to the porch....

The library is an unfinished room, 28' square. I'm pondering order of
operations. The shelves will be built-in on all 4 walls.

the question is: should I put the floor (probably maple) in first, and
build the shelves on top of it, or build the shelves first, and butt the
floor against them?

The shelves will be secured to the floor (roughly every 38"), and I am a
bit concerned with restricting cross grain wood movement if I put the floor
in first. However, most of the places where I've seen built-ins, they are
built over an installed floor.

I'd actually prefer to put the floor in last, so I don't have to worry
about scratches, gouges, and such but then, with a span of about 26' I'm
worried about expansion and movement. With a span that big, will the floor
trim be enough to hid any movement? We don't use A/C, and we heat with wood
in the winter, so humidity levels range from 95+% in summer to 35%-40%  in
winter. I've had no problem designing furniture to allow for that, but I've
never done a floor...

Am I being overly paranoid?

thanks
-j
275034 Bill Ghio 2022‑01‑03 Re: wood movement and construction question...
> On Jan 3, 2022, at 8:09 AM, James DuPrie  wrote:
> 
> I'm moving forward on the library project (year 2 now), and I figured I'd
> toss the latest dilemma to the porch....
> 
> The library is an unfinished room, 28' square. I'm pondering order of
> operations. The shelves will be built-in on all 4 walls.
> 
> the question is: should I put the floor (probably maple) in first, and
> build the shelves on top of it, or build the shelves first, and butt the
> floor against them?
> 
> The shelves will be secured to the floor (roughly every 38"), and I am a
> bit concerned with restricting cross grain wood movement if I put the floor
> in first. However, most of the places where I've seen built-ins, they are
> built over an installed floor.
> 
> I'd actually prefer to put the floor in last, so I don't have to worry
> about scratches, gouges, and such but then, with a span of about 26' I'm
> worried about expansion and movement. With a span that big, will the floor
> trim be enough to hid any movement? We don't use A/C, and we heat with wood
> in the winter, so humidity levels range from 95+% in summer to 35%-40%  in
> winter. I've had no problem designing furniture to allow for that, but I've
> never done a floor...
> 
> Am I being overly paranoid?
> 

Our floors are red oak. We are starting a remodel this week and just happed to
have some of the baseboard pulled up. The picture
( https://www.flickr.com/photos/77280442@N.../51795827107/in/dateposted/ ) shows
that the drywall does not extend to the floor and the flooring stops a full inch
from the stud wall. It would, of course, be the same at the other wall. This
space is 37 feet long and the two inches of gap have been sufficient. Where the
flooring runs long grain towards the wall, where movement is nil, the drywall
goes all the way down to the subfloor.  I believe the cabinets were installed on
top of the hardwood but will not confirm that till later in the week when demo
begins. My two cents is that I would install the floor first, that way yo can
hide a good gap under cabinets. Then just lay door-skin on top stuck down w/
carpet tape while you work in the room. My contractor says he will cover the
floors with heavy paper to protect them, but they are also planned to be sanded
and refinished as a last step since new flooring will need to be matched.

Good luck,

Bill
275035 Bill Kasper <dragon01list@g...> 2022‑01‑03 Re: wood movement and construction question...
my inlaws had a new oak floor installed a decade ago in their living room,
which is heated by a coal fire.  the floorers did it right to the lath and
plaster, no gaps, and within two years the floor had broken the plaster on
both ends of the floor.

when they reinstalled it they left about 3/8" , and put 1/2" or 5/8"
molding covering the gap.  no problems since.

i hardly think you'll have an issue from the shelves if they are on top of
the floor, even with them bolted through.  if you leave enough space at the
back of the shelves to move a bit, they can move with the floor and
subfloor.  but i am guessing rather you'd see the boards slide by (tongue
and groove i assume?) rather than buckle.

but i only play a flooring installer in a caillebotte painting...

best,
bill
felton, ca

On Mon, Jan 3, 2022 at 8:08 AM Bill Ghio via groups.io  wrote:
275036 Erik Levin 2022‑01‑03 Re: wood movement and construction question...
I can speak from limited experience only, and in a space much smaller (the
largest I have is 18'X12'). My house is climatically similar, varying from
sub-20% to 90+% humidity through the year. It's a good bit over 100 years old,
and the subfloor is 4X1-1/4", roughly, rough milled, gapped, somewhat twisted,
and over a century of other cracks, knots dropped out, checks, holes, and the
like.


I layed mine during the highest humidity time intentionally. I have had no
issues. I made a few compromises (letting the boards under the existing
baseboards rather than pulling them, figuring I could cover up with show molding
later. Then I realized that I dislike the few mistakes a lot less than I dislike
shoe molding. Shoulda pulled the baseboards) I get squeaks, in part due to
shrinkage and in part due to not leveling the subfloor as well as I should have.
But no buckling or large gaps. If I had put this down in the dry season, I have
no clue how I would have controlled it. As it is, in the dryest times, there are
perceptible gaps between the boards and where the ends butt up, but barely so. I
used rosin paper between the finish and the sub to control air movement and ease
the squeaks.

Hand nailed the whole lot through the house, as well as cut and fit the boards
in a galootish manner, including letting some of the boards to make up for the
unsquareness of the room, which took tapering about every third or fourth course
by maybe 1/16". Can't see it at all. Still have a few rooms to go, but I'm not
in any rush.


As far as the book caseing: One was installed before the floor went in, so I
butted to it, and it is ok. I think I may one day go back and redo the last
floor board and skirt board better. Or not. The other went in on top of the
finished floor. A neater job all around. I used a couple 2X on the finish floor,
and picked the anchor points carefully to allow future repair if the case comes
out. The skirt board covers all of that. If I needed, I probably would have slot
the attachments through the floor to allow for movement, but, again, I
intentionally did the install when the wood was swole up.


*** This message was sent from a convenience email service, and the reply
address(es) may not match the originating address
275037 David Sobel 2022‑01‑03 Re: wood movement and construction question...
My guess is that 1/2” for movement at each side will be sufficient, as much of
the movement of individual boards will be accounted for by adjustments at the
individual tongues and grooves. Is the edge boards actually moved a full 1/2”,
that would be more than the nails could easily accommodate.

My personal choice of whether to install the floor under the shelves would
depend upon the construction of the shelves. When I did something similar, but
much smaller scale, at a previous residence, i built the shelf to have the face
of the toe kick installed after the shelf unit was secured.  I installed the
shelf first, ran the flooring to where the baseboard would cover it, and then
scribed the baseboard to fit tight to the flooring.  The appearance is
indistinguishable from installing the flooring first.   You could also do it
with a baseboard and a shoe molding or quarter round, but I personally prefer to
scribe the base to the floor over using a shoe mold.

David Sobel
275041 James DuPrie <jbn.duprie@g...> 2022‑01‑04 Re: wood movement and construction question...
A clarification:
My concern with the shelves over the floor is that, because the shelves
need to be secured to the floor every 38", that they would cause problems
with floor being able to move as it expands/shrinks. The design of the
shelves is to have freestanding sides, anchored at top, bottom, and back.
The shelves are adjustable, so offer no structural integrity.
Of course, that means that if the sides are secured through the hardwood
flooring to the subfloor, there would be an immovable point every 38".....
If I install the floor under, and do it during the most humid time of year,
I guess the issue would go away, as all there would be is shrinkage.....

From what people have said (thanks!) 1/2" of expansion space on each end
would allow for any expansion across the whole floor, so if I did the floor
after the shelves, all I have to do is include some baseboard molding.....

thanks again....

-James

On Mon, Jan 3, 2022 at 8:09 AM James DuPrie via groups.io  wrote:
275042 Daniel Indrigo <dindrigo@g...> 2022‑01‑04 Re: wood movement and construction question...
Yes 1/2" to 5/8" should be more than enough, if the boards are moving 
more than that then the nails will be pulling out. As David said, the 
expansion/contraction should be mostly happening between individual 
boards. But you need to leave sufficient gap when installing. If it's 
extremely humid when you install then you can smack them together pretty 
tight, if instead it's quite dry then you need to make sure you leave a 
bit of a gap. You also need to consider heating from the sun if you have 
large south facing windows, that can cause all kinds of issues, if 
nothing else you may get a color change in that area. But you will also 
get more extreme movement in the area where the mid day sun will hit

As for which to install first I'd go with the shelves if they are likely 
to be a more permanent addition than the floor. At some point the floor 
may need refinishing/repairing and it will be easier if they just need 
to go around pulling up a quarter round around the edge.
275043 Micah Salb 2022‑01‑04 Re: wood movement and construction question...
James:

I've never seen bookcases that need to be anchored to the floor, but presuming
that that is in fact the case, the answer is simple:

Presuming we are looking at the cross-grain wall where there will be significant
expansion and contraction, remove a nice long slot before and behind the bolt-
hole so that there is room for the floor to expand and contract without the bolt
interfering.

I'd be inclined to look for two shims of a reasonably slippery material that I
could put under the bookcase to increase the ability of the floor to move
despite the bolted-down and heavy bookcases.  Maybe just a pair of stainless
steel plates?  I don't know if it is necessary but. . . .

Micah

-----Original Message-----
From: oldtools@g...  On Behalf Of James DuPrie via groups.io
Sent: Tuesday, January 4, 2022 6:42 AM
To: Tools Old 
Subject: Re: [oldtools] wood movement and construction question...

A clarification:
My concern with the shelves over the floor is that, because the shelves need to
be secured to the floor every 38", that they would cause problems with floor
being able to move as it expands/shrinks. The design of the shelves is to have
freestanding sides, anchored at top, bottom, and back.
The shelves are adjustable, so offer no structural integrity.
Of course, that means that if the sides are secured through the hardwood
flooring to the subfloor, there would be an immovable point every 38".....
If I install the floor under, and do it during the most humid time of year, I
guess the issue would go away, as all there would be is shrinkage.....

From what people have said (thanks!) 1/2" of expansion space on each end would
allow for any expansion across the whole floor, so if I did the floor after the
shelves, all I have to do is include some baseboard molding.....

thanks again....

-James

On Mon, Jan 3, 2022 at 8:09 AM James DuPrie via groups.io  wrote:

> I'm moving forward on the library project (year 2 now), and I figured 
> I'd toss the latest dilemma to the porch....
>
> The library is an unfinished room, 28' square. I'm pondering order of 
> operations. The shelves will be built-in on all 4 walls.
>
> the question is: should I put the floor (probably maple) in first, and 
> build the shelves on top of it, or build the shelves first, and butt 
> the floor against them?
>
> The shelves will be secured to the floor (roughly every 38"), and I am 
> a bit concerned with restricting cross grain wood movement if I put 
> the floor in first. However, most of the places where I've seen 
> built-ins, they are built over an installed floor.
>
> I'd actually prefer to put the floor in last, so I don't have to worry 
> about scratches, gouges, and such but then, with a span of about 26' 
> I'm worried about expansion and movement. With a span that big, will 
> the floor trim be enough to hid any movement? We don't use A/C, and we 
> heat with wood in the winter, so humidity levels range from 95+% in 
> summer to 35%-40%  in winter. I've had no problem designing furniture 
> to allow for that, but I've never done a floor...
>
> Am I being overly paranoid?
>
> thanks
> -j
>
>
> 
>
>
>
275044 David Sobel 2022‑01‑04 Re: wood movement and construction question...
Things are starting to fall in place a bit. The shelves will not be a series of
case pieces, but rather a series of vertical ‘sides’ permanently installed to
support adjustable shelves. The sides will extend from floor to ceiling. Have
you considered making the bottom row of shelves fixed?  This would hold the
sides square to the wall, and eliminate the need to attach the sides to the
floor.

One other thing that you may or may not have considered ( please pardon the
unsolicited advise if it is not needed): it is virtually guaranteed that the
floor and ceiling are neither flat nor level. To get a good set of level
shelves, you can’t count on either as a reference plane.     So the first order
of business is to mark a level line around the room at a convenient height for
measuring to the floor.  This line should correspond with a measured height on
the sides, such as the bottom of a shelf support. This becomes the reference
plane for installing the sides.  You can either make the sides a bit long on the
bottom and then scribe them to the floor, or make them so that the side at the
high spot of the floor is sitting directly on the floor, and then shim up the
others to the appropriate height. At the ceiling, the sides will all have to be
scribed to fit. Of course, if you stop the sides short of the ceiling and
install a fixed top shelf, you can save some installation labor since you won’t
have to individually scribe each side to the ceiling.

A laser works well for marking the level lines, but if you prefer something
closer to galootish, we used to use water levels and chalk lines back before
lasers were cheap and commonplace. A water level is just a flexible plastic tube
mostly filled with water and food coloring.  Since the water will seek its own
level, you can use this to transfer a mark at a given elevation from one
location to another. It’s a 2 person operation. One person stands at the
location to be marked and holds the tubing against the wall with the open end
pointing up. The other person stands at the reference mark with the other end of
the tube against the wall, raising or lowering it until the top of the water
aligns with the mark.  The. The first person can mark the wall at the top of the
water where it will be level with the first mark. Then a chalk line is snapped
between the two marks.

To be honest, an accurate 4’ level is also sufficient to draw the level lines to
the degree of accuracy needed.  But I am reaching the age where I find myself
saying, “ this is how we used to do it back in the old days…”.

David
275046 Don Schwartz <dks@t...> 2022‑01‑04 Re: wood movement and construction question...
On 2022-01-04 7:07 a.m., Micah Salb via groups.io wrote:
> I'd be inclined to look for two shims of a reasonably slippery material that I
could put under the bookcase to increase the ability of the floor to move
despite the bolted-down and heavy bookcases.  Maybe just a pair of stainless
steel plates?  I don't know if it is necessary but. . . .

I'd go with my default shims - discarded compact discs. They come 
pre-drlled and are a consistent thickness.

FWIW

Don

-- 
Omicron is coming fast. The time to act was yesterday.

Reading journalists' scribblings and listening to political commentators'
newscasts doesn't constitute independant research.
275049 Richard Wilson <yorkshireman@y...> 2022‑01‑04 Re: wood movement and construction question...
James is getting paranoid
(snippage) 

If ’twere me - and I have started on doing something similar for my somewhat
smaller study, when the new sotone sills are in and the windows, and the walls…

First question I’d ask Is about the shelving.  Sounds like ’spur’ brand library
shelving - the stuff that clips to a sltted metal upright.  Much used for
libraries, and with the uprights hidden within a wooden casing they would be a
good, strong, adjustable solution, as used in librarie around the globe.  Dsk
and box arrangements are possible, using the brackets sold for the purpose.  And
the floor would be clear, so running a vacuum around to keep the Domestic
Authorities happy is a delight.

But we’re asked about securing the uprights to the floor. 

If ’twere me, I’d design it with a plinth and toe inset, and have the uprights
run from there.  Why?  because it delineates the shelving and the floor, and a
sturdy plinth will spread the loads and provide a consistent datum.  Think of it
as a shelf 6” from the floor (something about skirting heigt (would that be
‘baseboard’ Paddy?)  A bottom panel of something substantial - moulding on the
front, good joints where necessary along the length, would provide the level
base point from which all the uprights spring.  Further, it means that piercing
the floor is no longer an issue, so eliminates many of the concerns that
prompted the question.  You could shim the base of the uprights and cover any
resulting gaps with a small moulding to each side (like a miniature skirting)
which would state that the upright springs from a solid base, and would prevent
anything going out of square.
I’d also be tempted to make the uprights at least appear substantial by adding
something to the front face - don’t want it looking as if its just a sheet of
MDF on edge - or maybe that IS the look to go for - but it needs to look
substantial enough to take the weight of books, and modern materials are
generally stronger than they look.

So, in summary - I’m suggesting altering the problem to make the flooring job
simple, and the shelving levelling and aligning simple and certain.

You could go on to make the top match the bottom of course. 


And when it all gets pulled out - you have a perfect floor and room.  



And now, back to my drawings for this place.  Heating, power, lighting - do I
want some concealed roof level lighting?  How do I handle the corners?  and the
printer’s 550 mm deep, so it needs a section of base that lets it be both
supported and mostly hidden - but needs to be accessible.  And the desk?  Do I
make it, find an old one?  Restore something?  How to run the cables, hide the
servers?
And after all that - come the questions about making and installing…. 

Don’cha just love doing these things?


Richard Wilson
Yorkshireman Galoot - letting sub-contracts in Northumberland






> On 3 Jan 2022, at 13:09, James DuPrie  wrote:
> 
> I'm moving forward on the library project (year 2 now), and I figured I’d toss
the latest dilemma to the porch....
> 
> The library is an unfinished room, 28' square. I'm pondering order of
operations. The shelves will be built-in on all 4 walls.
> 
> the question is: should I put the floor (probably maple) in first, and build
the shelves on top of it, or build the shelves first, and butt the floor against
them?
> 
> The shelves will be secured to the floor (roughly every 38"), and I am a bit
concerned with restricting cross grain wood movement if I put the floor in
first. However, most of the places where I've seen built-ins, they are built
over an installed floor.
> 
> 
> Am I being overly paranoid?
> 
> thanks
> -j
> 



-- 
Yorkshireman Galoot
in the most northerly county, farther north even than Yorkshire
IT #300
275051 John M. Johnston <jmjhnstn@m...> 2022‑01‑05 Re: wood movement and construction question...
James,  let me share my own experience and perspective.  In the past few years,
in two different houses, I've built several wall length floor to ceiling book
cases.  In both instances they were built on existing hardwood floors.

I hold hardwood floors in high esteem and would not consider nailing, screwing,
or bolting into them.  Further, it's not necessary for building a wall of
shelves.

I began by building a 2 x 4 base frame for the shelves, leaving enough room for
a toe kick in the finished unit.  I located wall studs and nailed the wall side
of the base frame into the studs and base plate.  I then used shims under the
front edge of the base frame so that it was canted about 2-3 degrees towards the
wall.

Then I made shelf modules, each about 25" wide and as tall as I desired.   I
used big box cheap pine about 12" wide for the bottom, sides, and top of each
module, and for the shelves as well.  At the inside top of each module, I
attached a horizontal stringer anchored to the sides and top of each module.  I
then arranged each module on the 2 x 4 base frame, checked the spacing between
each module, and then screwed the bottom of each module to the base frame, and
then through the horizontal stringer at the top into the wall studs.  So the
base frame sits on the floor (gravity) is nailed to the wall studs, each module
is nailed to the base frame at the bottom, and at the horizontal stringer at the
top.  They ain't going anywhere, and the original oak floor is undefiled.

At this point it was just a matter of adding the trim:  vertical pine boards to
cover the spaces between the modules and corresponding horizontal pieces at the
top and bottom to form a face frame for the entire unit; a toe kick board to
cover the 2x4 base frame, and various mouldings to make it look nice and
finished.  It turned out well and was built with stock lumber and trim bits.  I
see your email address so I'll send you a photo to illustrate what I mean.

Hope this is helpful.

Cheers,
John

John Johnston
275052 Praki Prakash <praki.prakash@g...> 2022‑01‑05 Re: wood movement and construction question...
This is more or less what I too have been planning to do except for the use
of plywood rather than pine. The 12inch wide pine I bought from hd started
twisting and cupping badly after I cut dados and I had to abandon that
project.

I would love to see a picture of your bookshelf.

Thanks,
Praki

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