Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

Please, take this question seriously, because this is a real problem to me. I have a door in my flat. A closet door, to be specific. And there is a problem with it.

In the summer everything is ok, the standard wood door opens and closes as predicted, but in the winter time it drives me crazy! It just won't close! Seems that it doesn't fit where it belongs. Damn door just doesn't allow me to welcome guests and take a cup of mulled wine with them.

So the question is, what physical processes are standing behind that unfitting? I believe that sun and gravity may be involved, but I don't really understand it. So, please, help. If I'll know the problem, I'll figure out a solution.

P.S Maybe it is important that I live in Kazan', Russia

share|improve this question
add comment

7 Answers

up vote 10 down vote accepted

I would say it has to do with humidity, since it is a wooden door. It probably gets too humid during the winter and the wood expands. If it had to do with temperature, it would be the opposite effect (it would expand during the summer when it is hot).

share|improve this answer
2  
i think humidity is the culprit too. it's generally actually drier in the winter, and dry wood tends to shrink, and it just may be that his whole house shrinks a bit, and the door, less so. –  JustJeff Dec 4 '10 at 19:25
3  
Yes, it could also be a problem with the frame of the door. –  Vagelford Dec 4 '10 at 19:33
1  
Just checked the climate of Kazan on the wiki page and it is indeed a humid continental climate. I must say though, it's not clear to me if the OP is saying that the door doesn't close because it is too small to fit or too big to fit? –  Raskolnikov Dec 4 '10 at 20:18
1  
I've considered this, yet I'm afraid humidity is much more variable than temperature, while OP states that the effect is strongly season-dependent. The argument about what should expand is really irrelevant, since we have not enough information to analyse detailed mechanism. –  mbq Dec 4 '10 at 23:54
    
@Raskolnikov Too big, seems like it had increased its volume. Or something else had increased its volume. –  Daniel Excinsky Dec 5 '10 at 8:10
add comment

Seasonality suggest it has something to do with thermal expansion; yet if you seek for solution, it is better to ask on http://diy.stackexchange.com.

share|improve this answer
add comment

It's actually just that in winters or around that time water doesn't evaporate that fast. So, the cellulose in the wood expands due to the added water content and swells until it doesn't fit the door frame. (1)

It's really interesting just how beautifully everything plays out in nature. If you think about it that property probably saved a lot of trees from dying. If wood expands in moisture that means the tree will be taller in just the right conditions. It contracts that means the tree will be shorter in just dry conditions. That, probably, reduces the surface area of evaporation and helps the tree to survive. I might be wrong, but it's mind boggling just how awesome nature is. She rocks. :D

(1) Cellulose is a polymer and I guess the expansion might have something to do with hydrogen bonding interacting with it's structure.

share|improve this answer
add comment

I have the exact same issue with my bathroom doors. It is generally cooler in there during the winter. Since its my bathroom, the doors suffer a heavy dose of water (its humid). But this problem ONLY occurs in the cooler months. Could it be the metal door hinges, handles, locks, nuts and bolts that contract? If those mechanisms were to shrink in size, it would displace the door's positioning....thus preventing it from shutting.

share|improve this answer
add comment

I have a similar problem with a garage door (backdoor, not the car entrance). Here in California winters can be vert wet, while summers are bone dry. I've spent hours shaving wood off the edges, to keep it from getting too bad. Stresses and strains on other parts of the structure might also be to blame.

share|improve this answer
add comment

I have the same problem with my doors in Concord California. The reason seems to be the cememt slab. During the Dry weather the ground is dry and the house slumps. In the winter when the soil is wet the house rises up and everything fits differently. I could water my slab (plant close to the wall some water loving plants) or live with it. Water costs and hassle keep me from doing that so it keeps settling. You could plane off the door so it's a little smaller to make it fit in the winter and be a little small in summer. Just observe where it sticks and with your wood plane shave a little off till you like it.

share|improve this answer
add comment

I have doors like that too. Probably everyone in a climate where it gets reasonably cool does too. Other interesting effects include cracks that open/close based on temperature. Appears that the house shifts slightly during seasonal changes. Possibly due to temperature differences that the house generates in the ground resulting in asymmetrical movement? Humidity appears to be a near non-issue (it does have some effect, but never enough to make the difference between working and not working).

share|improve this answer
add comment

protected by Qmechanic Oct 26 '13 at 14:24

Thank you for your interest in this question. Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.