Fitting an Internal Door
It is not simple fitting an internal door. However, it is not too difficult if you know what you are doing. Is this not usually the case? We will consider the replacement of two types of doors, the traditional swing door and a sliding door. The information included here follows the practical fitting of both types of doors.
It all starts with the purchase of replacement doors, and here there is a large range to choose from. For example you have the plain faced door, or a more elaborate door with fancy timber sections, or a step up to glass panels on the timber door. All these matters will be to your taste, budget and choice, but what you need to be absolutely certain about is the dimensions of the door. Take the time to measure the doorway accurately, ensuring you do not do something silly like 2300 mm instead of 2030 mm if the measuring is in metric. When you are replacing an existing door it is likely sufficient to measure the existing door. If you are measuring the doorway you will need to allow for the small gaps at top and bottom and some space at the sides. Take your time and get this right because it all follows from this starting point.
Discuss options with the door supplier because they can supply a door that is already primed for undercoating, or you will need to prime first. If you need to prime you may elect a dual prime and undercoat paint. The supplier will likely provide a low cost service to cut the door to your specified dimensions. For a sliding door this can include the groove in the bottom of the door for which you would need to use a router. You can decide all this based on price and convenience when you are talking to the supplier’s representative. Remember to allow for any extra requirements such as sliding rails for the sliding door, and knobs and hinges for the swing door, unless you will re-use the existing fitting. It is likely the existing fittings will be rather well worn if the door has been up for a long period of time.
These are not so difficult to install. The starting point is fixing the railings the door will hang from. Dimensions should all be included in the railings package. Start by using a level to carefully check the level of the existing railing and the level of the floor. Also, I suggest you check the vertical door jams, because the door will be closing onto what should be square and perpendicular to the floor.
Before installing the door handles, make sure you decide their position, especially height. Remember the two handles will most likely be positioned at the same height and location on the door. Take time to get this right, double checking. The cut-outs for the handles should be marked in pencil on the door then carefully marked out with a nice sharp chisel. I will assume you know how to do this. The height of the handles should be carefully assessed, likely just above waist height will be ideal. Once you fit the handles you have determined which side of the door will be facing each room.
The wheel assemblies can be fitted to the top of the door, about 7.5 cm, that’s around 3 inches from each end at the top. Find the center point by measuring or use a thumb gauge to mark approximate center from each side and the center will be mid those marks. I am sure there are many ways to do this.
It will be important to have the railing at a height that leaves perhaps a 10 mm gap to the floor. Remember that floors are unlikely perfectly level and the door has to clear the floor when fully closed and when fully open. Additionally the plastic door guide will be fixed to the floor and the door needs to clear the guide. Get the height right, allowing for a plus or minus 5mm (about one fifth of an inch) that will allow final fine tuning adjustments, especially so that the door closes neatly at the top and bottom of the doorway when closed. When you are deciding the length of the railing remember that you will need access, probably minimum 2 inches or 50 mm. at one end to slide on the wheel assemblies and the door stops.
Tip: remember to have the railing level as well as the correct height. This is most important because the door will automatically slide open or closed if the railing is not level.
You slide the door on to the wheel assemblies from the side so that you fit the wheel assemblies to the railing and then fit the door to the wheel assemblies. Fitting the door is easier if you rest the door on a suitable piece of timber around 10 mm or two fifths of an inch thick. Final adjustments are made via the screw-threads on the wheel assemblies fixed by lock-nuts.
Before starting just place the door up to the doorway to check that it will fit correctly. The critical dimensions are the cut-outs for the hinges, likely chiseled out. Ensure the measurements are accurate and do not dig out too much wood or you will need to shim to correct. It will assist if you have a suitable piece of timber under the door to get the height correct without having to hold up the door.
To fit the handles and tongue of the locks I strongly suggest you invest in a door fitting kit (around $30 investment) that you clip on the door to guide drilling. Included in the kit I purchased are the hole-saw attachments and a plastic guide to router out the lock plate fitting. Whether or not you have a kit it is again important to get the positioning and hence measurements very accurate. This will allow for variations that are unavoidable despite your best intentions.
The result of fitting an internal door yourself should give you a great deal of satisfaction, just take your time and check and recheck, because it is important to avoid any simple mistake or measurement error, and the second one will be easier still.
About the author: Ronald Heron draws on a lifetime of experience with building and woodworking.