[Ken]

I'm talking about the typical situation where a wood door starting to stick in humid weather. I plane the door so that it no longer sticks in the jamb, and then everything is fine until a year later when it gets humid again and the door has expanded yet again and sticks.

I'm a woodworker, and fully aware of the effects of humidity expansion and contraction. I have an end-grain stick cut from the end of a tabletop I built that I measure it's length and use as a gauge to know where in the expansion and contraction cycle the environment is currently in. I always seal all 6 sides of the door in question to limit the magnitude of the expansion and contraction due to humidity.

The thing that I can't figure out is why do wood doors always only grow larger over time? I have numerous doors that I plane to fit very nicely, and then several years later I need to plane again because they have expanded larger. Never in my life have I ever seen a door that shrinks due to low humidity and causes an excessively large gap. I see this on both interior and exterior wood doors.

So what is it about the expansion/contraction cycle that appears to be biased toward expansion?

Ken

[dpb]

On 8/22/2011 8:46 PM, Ken wrote:
I'm talking about the typical situation where a wood door starting to
stick in humid weather. I plane the door so that it no longer sticks
in the jamb, and then everything is fine until a year later when it
gets humid again and the door has expanded yet again and sticks.

I'm a woodworker, and fully aware of the effects of humidity
expansion and contraction. I have an end-grain stick cut from the
end of a tabletop I built that I measure it's length and use as a
gauge to know where in the expansion and contraction cycle the
environment is currently in. I always seal all 6 sides of the door
in question to limit the magnitude of the expansion and contraction
due to humidity.

The thing that I can't figure out is why do wood doors always only
grow larger over time? I have numerous doors that I plane to fit
very nicely, and then several years later I need to plane again
because they have expanded larger. Never in my life have I ever seen
a door that shrinks due to low humidity and causes an excessively
large gap. I see this on both interior and exterior wood doors.

So what is it about the expansion/contraction cycle that appears to
be biased toward expansion?

Ken

What kind of door (construction, material (solid/veneer/mdf), etc., etc., )?

In solid doors I see the shrink/swell cycle regularly; I'd suspect
something else going on other than just humidity changes...

--

[Frank[_13_]]

On 8/22/2011 9:46 PM, Ken wrote:
I'm talking about the typical situation where a wood door starting to stick in humid weather. I plane the door so that it no longer sticks in the jamb, and then everything is fine until a year later when it gets humid again and the door has expanded yet again and sticks.

I'm a woodworker, and fully aware of the effects of humidity expansion and contraction. I have an end-grain stick cut from the end of a tabletop I built that I measure it's length and use as a gauge to know where in the expansion and contraction cycle the environment is currently in. I always seal all 6 sides of the door in question to limit the magnitude of the expansion and contraction due to humidity.

The thing that I can't figure out is why do wood doors always only grow larger over time? I have numerous doors that I plane to fit very nicely, and then several years later I need to plane again because they have expanded larger. Never in my life have I ever seen a door that shrinks due to low humidity and causes an excessively large gap. I see this on both interior and exterior wood doors.

So what is it about the expansion/contraction cycle that appears to be biased toward expansion?

Ken

I always suspected minor house settling getting things out of square
etc. But, now, thinking about it, the wood may actually continue to
expand due to moisture uptake and drying cycles. I know this can happen
with nylon parts.

[Ken]

On Monday, August 22, 2011 11:53:27 PM UTC-4, dpb wrote:

What kind of door (construction, material (solid/veneer/mdf), etc., etc., )?

In solid doors I see the shrink/swell cycle regularly; I'd suspect
something else going on other than just humidity changes...

--

These are all wood doors, but I see it happening on either solid wood doors (typically exterior) or veneer (interior with a solid glued-up core with veneer over that). This is in old houses from the 1920s, so there should have been plenty of time for the humidity expansion/contraction cycle to "settle out" into it's summer maximum and winter minimum range.

I didn't mention before that I'm in the Northeast US, so we have humid summers (and no A/C in the house), and cold winters with forced air heat. So I completely understand that there should be large swings in expansion and contraction due to humidity.

The thing is that the summer maximum seems to continuously increase and I have to keep planing doors. There is one interior door on the first floor (sits on a solid foundation, so there is little or no structural movement over time) that has expanded so much I needed to remove the mortised lockset, plane the strike side of the door about 3/16", cut the mortise deeper, and then reassemble everything. And that wasn't the first time that door had been planed. In that case I figured planing the strike side was easier than planing the hinge side and having to re-mortise two hinges.

The point to all this is that some doors have "grown" more than 1/4" in width since the house was built.

Ken

[dpb]

On 8/23/2011 11:11 AM, Ken wrote:
On Monday, August 22, 2011 11:53:27 PM UTC-4, dpb wrote:

What kind of door (construction, material (solid/veneer/mdf), etc., etc., )?

In solid doors I see the shrink/swell cycle regularly; I'd suspect
something else going on other than just humidity changes...

--

These are all wood doors, but I see it happening on either solid wood
doors (typically exterior) or veneer (interior with a solid glued-up
core with veneer over that). This is in old houses from the 1920s,
so there should have been plenty of time for the humidity
expansion/contraction cycle to "settle out" into it's summer maximum
and winter minimum range.

I didn't mention before that I'm in the Northeast US, so we have
humid summers (and no A/C in the house), and cold winters with forced
air heat. So I completely understand that there should be large
swings in expansion and contraction due to humidity.

The thing is that the summer maximum seems to continuously increase
and I have to keep planing doors. There is one interior door on the
first floor (sits on a solid foundation, so there is little or no
structural movement over time) that has expanded so much I needed to
remove the mortised lockset, plane the strike side of the door about
3/16", cut the mortise deeper, and then reassemble everything. And
that wasn't the first time that door had been planed. In that case I
figured planing the strike side was easier than planing the hinge
side and having to re-mortise two hinges.

The point to all this is that some doors have "grown" more than 1/4"
in width since the house was built.

Ken,
Ya' got me...any chance of posting some pictures on one of the hosting
sites?

In an earlier life did a lot of restoration on old Federal and earlier
(some ante- many shortly postbellum) in the Lynchburg, VA, area, that is
also quite humid in summer, relatively drier in winter but not,
obviously, nearly as cold as the NE could be. I never ran across such
an experience there even with the sometimes very large doors.

Currently in '10s-built farmhouse also w/ original solid frame and panel
doors and there's never been such an observation, either. This is, of
course, a much drier climate but far more extreme in temperature swings.

I'd suggest posting the question to rec.woodworking; there are some
others there w/ lots of experience in your area plus some others in wet
climates that might have some ideas; this being such an apparent change
in width is not anything I've ever observed.

The thing is, long-grain doesn't expand/contract w/ moisture at all (in
comparison as you obviously know) so all the change in dimension for a
conventionally-constructed panel door has to come from the stiles which
one would presume are only something like 6-8" each. The amount of
dimension change over that distance that you're seeing is remarkable...

Any idea the species of the wood out of curiosity?

--

[Reed]

On 8/23/11 12:11 PM, Ken wrote:
On Monday, August 22, 2011 11:53:27 PM UTC-4, dpb wrote:

What kind of door (construction, material (solid/veneer/mdf), etc., etc., )?

In solid doors I see the shrink/swell cycle regularly; I'd suspect
something else going on other than just humidity changes...

--

These are all wood doors, but I see it happening on either solid wood doors (typically exterior) or veneer (interior with a solid glued-up core with veneer over that). This is in old houses from the 1920s, so there should have been plenty of time for the humidity expansion/contraction cycle to "settle out" into it's summer maximum and winter minimum range.

I didn't mention before that I'm in the Northeast US, so we have humid summers (and no A/C in the house), and cold winters with forced air heat. So I completely understand that there should be large swings in expansion and contraction due to humidity.

The thing is that the summer maximum seems to continuously increase and I have to keep planing doors. There is one interior door on the first floor (sits on a solid foundation, so there is little or no structural movement over time) that has expanded so much I needed to remove the mortised lockset, plane the strike side of the door about 3/16", cut the mortise deeper, and then reassemble everything. And that wasn't the first time that door had been planed. In that case I figured planing the strike side was easier than planing the hinge side and having to re-mortise two hinges.

The point to all this is that some doors have "grown" more than 1/4" in width since the house was built.

Ken

My daughter's house in CT built 1955 has the same problem. Original
hollow core (mahogany veneer over pine core) doors need
planing/rasping every year for the 8 years they've been in house. Plus
re-mortising at times

Can wood still "grow" after being cut, milled, etc ????

[Joe]

On Aug 22, 8:46*pm, Ken wrote:
I'm talking about the typical situation where a wood door starting to stick in humid weather. *I plane the door so that it no longer sticks in the jamb, and then everything is fine until a year later when it gets humid again and the door has expanded yet again and sticks. *

I'm a woodworker, and fully aware of the effects of humidity expansion and contraction. *I have an end-grain stick cut from the end of a tabletop I built that I measure it's length and use as a gauge to know where in the expansion and contraction cycle the environment is currently in. *I always seal all 6 sides of the door in question to limit the magnitude of the expansion and contraction due to humidity.

The thing that I can't figure out is why do wood doors always only grow larger over time? *I have numerous doors that I plane to fit very nicely, and then several years later I need to plane again because they have expanded larger. *Never in my life have I ever seen a door that shrinks due to low humidity and causes an excessively large gap. *I see this on both interior and exterior wood doors.

So what is it about the expansion/contraction cycle that appears to be biased toward expansion?

Ken

You've made a compelling argument for fiberglass doors...

Joe

[dpb]

On 8/23/2011 1:15 PM, Reed wrote:
....

My daughter's house in CT built 1955 has the same problem. Original
hollow core (mahogany veneer over pine core) doors need planing/rasping
every year for the 8 years they've been in house. Plus re-mortising at
times

Can wood still "grow" after being cut, milled, etc ????

W/ a slab door it's not so hard to imagine since the full width is all
vertical grain for movement. Or, a composite interior could continue to
swell some. But even there for it to continue year after year seems
quite unusual.

No to the last question to anything other than movement owing to
changing of properties owing to primarily moisture equilibrium changes
and to a much lesser degree some temperature. "Real" wood growth
diameter happens only on the outer surface at the cambium layer under
the bark; the interior sap- and heartwood sections have already grown
all they ever will once the year's spring and fall growth season are
over the year they are produced; those never get any larger.

(Although there are instances of green lumber being harvested and
sprouting new growth if left enough intact and in nurturing-enough
conditions, mostly places like jungles, etc., that's not the case
certainly w/ processed lumber such as is in a door that as well as being
quite a long time removed from any living material still present has
likely been through a dry-kiln as well...)

--

[Ken]

On Tuesday, August 23, 2011 1:26:22 PM UTC-4, dpb wrote:

The thing is, long-grain doesn't expand/contract w/ moisture at all (in
comparison as you obviously know) so all the change in dimension for a
conventionally-constructed panel door has to come from the stiles which
one would presume are only something like 6-8" each. The amount of
dimension change over that distance that you're seeing is remarkable...

Yeah, that's why I'm amazed by all this. These are mostly rail and stile single panel doors, so the percentage across the stile width seems large.


Any idea the species of the wood out of curiosity?

Exterior doors are solid softwoods, don't know the species.

Interior doors are solid wood rails and stiles with plywood panels, and thick (3/32 - 1/8") gumwood veneer over everything. The solid wood is glued up miscellaneous hardwoods. On the top and bottom of the doors where there is no veneer, I can see 3-5 narrow sticks glued up to get the 6" width for the stiles. I can tell some of it is oak, but there are some other tight-grained hardwoods in there too that I can't identify.

[Bill[_9_]]

Also paint the top and bottom of the door when new, then humidity
can't get in...

[Ken]

On Thursday, August 25, 2011 11:50:55 AM UTC-4, Bill wrote:
Also paint the top and bottom of the door when new, then humidity
can't get in...

Yep, I always paint all 6 sides of a door.