The process of replacing internal doors - help

3 Aug 2014
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United Kingdom
I am going to replace some internal doors in the house. Not spending crazy money will be just replacing them with the cheap pre primed 6 panel doors. You might wonder why not get better ones? Well Just dont have budget for spending alot more, and hounestly even though they are cheap they look million times better than my current doors! (Flat door in this ugly mahognnay style thing).

I have found many great videos and tutorials online on how to hang a door, but cannot seem to find any really on how to size up the door, or how to replace a door into an older frame. Most videos are putting a new door into a new frame. Last year I renovated a door downstairs and was not as knowledgeable, hinges dont sit right and it all needs fixing. Which is fine, I am going to do this. I just dont want to have same problems as before!

Few issues I can see;

1 - Current doors are 35mm deep and are not painted. I've noticed all the door jambs are pretty much 35mm deep. As I am painting the new doors with potentially 2 undercoats and 2 top coats, hopefully less, I am concerned about the door being more than 35mm and then it not closing correctly etc. When I was painting other side of door frame, the new paint made some of the doors be a bit sticky as the fit was pretty tight, and that was just from bit of paint "bubbling" at the edge of the jamb. (does that make sense?) I sanded it, but I have not even painted the side where door meets jamb, and it will need painted. I have not painted any of the room sides of the doors, and the frames have had gloss paint on them. Will need sanded etc. What about moving the door jambs? Is this a possibility or would it be easier to try to somehow trim out a mm or 2 ? Not the easiest thing to do. Ive no idea how the jambs have been attached, but it is a 1975 house and most things have been nailed so I doubt its screwed in.

2 - Current hinge sizes are not any size I can find in the shops, so I am either going to be smaller or bigger. I am actually thinking of getting slightly bigger ones for a neater flush finish. Current ones are 90mm in height, so will get 100/102mm ones.

3 - When to paint? So this is something I can't really get an answer on. When should I paint the doors. Before or after hanging them? Reason being about the extra couple mm from paint will effect things? I have sizes of current doors, and can trim to that, but should I be trimming an extra mm off for paint?

Sorry for the wall of text, hopefully someone can help me out a bit at least?

Thanks in advance!
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they will be 3 1/2"[88.9mm]
remove the door stop temporary hammer 2 nails in each side

if the doors are a good fit then use them as a template

usually the maximum you can remove from a door is between 5 and 12mm dependent on manufacturere
Thanks big-all. What about when to paint them? And 2mm for paint allowance?
1mm max for paint unless you are using a trowel or 20 coats off paint
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I don't even understand why you are asking when to paint the doors? How why would you even paint a door properly that was not already hung?
1) Remove old door
2) Measure frame -use these dimensions to buy a new door as close as you can get (cheap doors allow you to trim off about 10mm at most. Try to get a size that requires less trimming than this!).
3) Cut rebates into the door frame for the new hinges, if required. Drill a pilot hole for one screw per hinge at this stage.
4) Offer door up to doorway and note where it needs trimming.
5) Trim door as required. Try to do this only by planing off the latch side, not the hinge side. You want to keep the hinge side as straight as possible. Only trim off enough to make the door a tight fit at this stage.
6) Tape a coupel of 2p coins to the top of the door to act as spacers. Offer door up to aperture. Put wedges underneath to raise it until it is jammed against the top of the door frame.
7) Mark the positions of the hinge rebates onto the door.
8) Remove door, fit hinges to it (use all screws; make sure you get the hinges the right way round)
9) Hang door -just use one screw per hinge at this stage, into the frame. Note any areas on the latch side of the door that need further shaving.
10) Remove door. Plane as required. With very warped frames you may need to hang it and remove it several times to get an exact fit.
11) Hang door and fit all screws.
12) Remove door for the final time and paint (or paint in situ, it's up to you...)
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just to add to gerrydelasels advice

your door may have a "H" and "L" marked on the top to denote which side has the lock block unusual but possible
Thanks for the lengthy replies. I am not too concerned about making the door to fit width and height as I have existing doors and I am confident with doing that. Problem was with the depth of the door is the same as gap from edge to door jamb then with paint added could make it a bit sticky. But I think I will manage.

Thanks for all advice, will be tackling this soon.
I would warn that the existing hinge points may be weakened if doors have been removed or re-hung previously. If there are any cracks or weakness apparent when you remove the old hinges you may be well advised to apply filler to the locations of the old hinges, and cut new hinge locations for your new door. That way you're not putting the new screws into a section of frame which is significantly weakened.
Drill pilot holes where the screws go to prevent the frame (and door edge) from splitting before you drive in the screws. trust me this is important.
It's impossible to paint the bottom of the door after it's hung. To prevent to door absorbing moisture though this surface it must be sealed with varnish or paint before you hang it. It will be unsealed as sold because you may need to remove some mms of timber to fit your existing frame. Once your door is trimmed you should seal this surface before proceeding to avoid warpage / bulging / shrinkage of the bottom of the door due to temperature and humidity changes through the year.

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