A heavy solid mahogany front door would expand and stick when the weather was damp and work fine in the dry sunny weather. So to stop it absorbing moisture i waiited for very dry weather and put a varnish all around the edges. Not it sticks all the time. Would the varnish stop it drying out? If so why didn't it stop it absorbing moisture?
You probably had a "too close" fit in the first place, and the additional thickness (and tackiness) of a film finish has used all the spare space and made it more likely to stick.
(It is very difficult to get a complete impermeable hermetic seal on wood that is good enough to stop seasonal movement (short of putting a thick layer of epoxy all over it).
Probably time to bite the bullet, take the door off, and plane it to fit with a few mm spare.
I think you are being over simplistic. Water could be getting in anywhere. My old front door has warped as well. Indeed the upvc one won't lock in hot weather, so really I guess its always going to be an issue. Brian
You probably didn't apply varnish to the underside of the door and the endgrain there is likely to absorb water
I had a similar problem many years ago on the outside door to a conservatory. I applied silicone grease to the underside of the door, hoping it would penetrate the wood and prevent further water absorption. I used silicone grease so that the wee beasties of this world wouldn't be attracted to it and just gobble it up.
But it was a long time ago in a previous property, and with my diminishing powers of recall, I can't remember if it was effective :-( Might be worth a try though.
And use a proper basecoat sealer intended for hardwood doors that will then be stained or 'varnished'. These also stop the bottom of the door showing those nasty black marks under the varnish because of moisture getting into the wood.
Finding a decent solvent-based sealer will not be easy and the VOC2010 water-based replacements are not really good enough for hardwoods (depending on the type of wood).
External wood needs to be primed (painting) or sealed with a basecoat sealant (staining and varnishing).
There are still argumentative 'pro' painters who think that the bottom and top edge of a timber door should not be painted at all so that it can 'breathe'. This is of course utter cobblers. It's just because having fitted the door it is too much effort to remove again and apply some primer to the awkward bits.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.