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How To Fix a Swollen Wooden Door

This is one of those home repair dilemmas where everyone offers their opinion and advice only to end up having to the replace the door rather than just fix it.






How do you fix a swollen wooden door? The answer is... you don't. Think about it, timber expands and contracts according to the surrounding ambient temperature, moisture, or humidity. When it is hot, the cell structure within the timber contracts as the moisture in these cells evaporates. But when it is raining or there is high humidity or precipitation, the cells within the timber expand as they soak up moisture. This is when wooden doors - both indoors and outdoors - tend to become swollen and difficult to open or close. This can affect all kinds of wooden exterior doors, including sliding and French doors.


When purchasing a new door at your local Builders store, or having new doors fitted, they are not always given a coat of sealer or varnish beforehand, in fact, it is better if they are not, and you can then ensure that they are properly treated and 100% weatherproof. There are a few steps to follow when fitting a new exterior door to your house.









Fitting a New Door


1. Before Fitting the Door

When bringing the door home or having it delivered the first thing you need to do, or have someone do for you, is to apply a quality exterior sealer to the door. That includes the front and back of the door as well as ALL the edges. Too often, a door is fitted and only then is a sealer applied. When it is done this way, the top and bottom of the door are often overlooked or forgotten and yet, the top and bottom are the surfaces that require the most protection from the elements. Only use a reputable sealer for this project, as anything less may fail and the door become irreversably damaged.


GOOD TO KNOW: Any sealer applied to exterior timber needs to be re-applied every 12 to 18 months or sooner if the wood starts to go dull.







2. Fit a Weatherproofing Strip

If an exterior door is often buffeted by winds and rain or is in an area where rainwater tends to pool, have a weatherproofing strip fitted to the front of the door at the bottom. This strip will prevent rainwater from gaining access under the door and reduce swelling due to water absorption. Builders stock a selection of weatherproofing strips and other weatherproofing projects.



3. Fit Foam Rubber Seal

Another way of protecting wooden doors from our climate is to fit a foam rubber weatherproofing strip around the door frame or door. This soft foam strip has a self-adhesive backing and is easily applied and cuts down on winds and water creeping through the gaps around the door. I purchase a self-adhesive foam rubber sealing strip at Builders that I fit around door and window frames. This product usually lasts around 5 - 6 years before it needs to be replaced.



4. Fit the Door Properly

Doors are manufactured in specific sizes, and you will need to select the best fit for your property. One thing to keep in mind is that you will probably need to cut off at the top or bottom of the door for it to fit, but you may also have to use a planer on one side of the door if it is a tight fit. This is also where you should make allowances for any expansion or contraction of the wood throughout the seasons. A door that is not sufficiently wide enough will allow draughts through while one that is a tight fit will stick when it swells.


If you follow the above steps, you should not have any problems in the future.



When a wooden door looks dull and lacks any shine it is a sure indication that a quality exterior sealer needs to be applied immediately.



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Fixing an Exterior Door

If you need to fix an interior or exterior door that is sticking, just keep in mind that it will go back to its usual shape once it dries out. Any swelling is only temporary, and you can quite easily speed up the drying process by using a hairdryer, heat gun (not too close) or by plugging a dehumidifier if the door leads to a bathroom, kitchen or laundry.  If you are sure that the door getting stuck is not due to moisture, sanding the affected area and then repainting or sealing will solve the problem.







Even hollow-core interior doors are susceptible to swelling and if this occurs, wait for dry weather before lightly sanding away the surface area that sticks.




Now that you are aware of what causes the door to swell, you can remove it from its hinges and apply a quality exterior sealer to prevent any future swelling.






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