On 4/18/2012 1:59 PM, Rebel1 wrote:
This house had a double wooden entry door, each door being about 40"
wide. One is rarely used; the other is for everyday use. The everyday
door is bowed at the latch side toward the inside of the house by about
1/8-3/16". (The hinge side is okay.) So to engage the latch and
deadbolts into their strike plates, one must push the lock area really
hard toward the outdoors or slam the door closed hard.

....

The real question is why should just one of the doors warp? Both are
exposed to the same temperature differentials. Both doors have outer
storm doors with glass panels during New Jersey's winter season. The
colors on both sides of both doors match, but I can't guarantee that
both sides of both doors are painted with the same type paint (latex vs.
oil). The house was built in 1993.

Assuming "wooden" means solid wood (as opposed to veneered MDF, etc.,
alternate construction) any number of possibilities, virtually all
centering around moisture and movement of same.

It's possible the one wasn't as well-selected piece of stock originally
as the other so there's more grain to deal with (ideal would be
quartersawn as opposed to plainsawn); that's the luck of the draw and
how well the doors are built originally.

More than likely there is a difference in whether the top/bottoms have
also been finished, how much wear of that finish at the bottom, say,
from the threshold has removed the finish and then allowed moisture a
way in preferentially. Also, the side that is used also probably does
get more direct impact from what weather there is as the storm on that
side will be opened much more often to allow same; over a period of time
that may have had an accumulative effect as well.

Is there any change in the amount w/ seasons, weather, etc.? That would
be dead giveaway you do have a moisture penetration problem.

A differential in the amount of direct sun owing to shading of one side
preferentially because of direction facing, etc, could also be a factor.

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