Additions to the interior door: what is it, types, do-it-yourself installation

If you put a door frame and it is smaller in width than the thickness of the wall, this gap must be closed with something. To do this, use the extensions on the interior door. About what they are, how they look, what they are, how to put them, and we will talk further. 

What is dobor

When installing interior doors, a situation arises when the box is less wide than the thickness of the wall. In such cases, a special board is used, which is attached to the door frame, closing the remaining space. This board is called the addition to the interior door. There is also the name “additional board” and “additional plank”. Then you can attach a casing to it, which will close the gap between the extension and the wall.

That is, the door dobor is an additional part of the door frame. It is a board of certain sizes, which is joined to the door frame. They put it on one side – opposite to the one into which the door opens. You can also call this board an expander – it displays its real purpose.

There may be nuances in the docking of the dobor. Often the shape of the door frame is specific – with a special relief (protrusions, depressions, roundings). Then you will have to look for an extension of this particular company, otherwise it will be problematic to dock them.

Materials and dimensions

Each of the manufacturers produces a certain set of additional boards, in which the length is fixed – 230-250 cm, the thickness / width changes. For example, there are such options (thickness, width, length):

• 10*50*2350mm;
• 10*100*2350mm;
• 15 * 150 * 2350 mm.
  

Thickness and width – each factory has its own. Can be 60 mm, and 65 mm or 75 mm. In general – any set. What if none of them is suitable for your case? Take a larger width than required, then saw off the excess. And if your opening is wider than all available options? Order the right size (many manufacturers make to order) or splice two smaller sizes. Another option is to use telescopic architraves. They come with a fold around the corner, which can cover your lack of width.

What materials are used for interior doors? Of the same as the platbands:

• wood;
• MDF;
• Chipboard.

MDF and chipboard can be veneered, laminated. Wooden ones can be with or without processing. Match the material and color to the door frame. And this is another reason to take from the same manufacturer – even if the name of the color / texture matches, there is no guarantee that they will actually be the same.

Types of extensions

There are two types of doborny board:

• With straight edges. An ordinary board, which is attached end-to-end with a box. May be:
  • with decorative edge;
  • without decorative edge.
    

• Telescopic extension. With molded grooves for connecting to the box.

Dobor on an interior door with straight edges – the most common board. In this case, it must be selected only by color and size. The dobor is pressed against the box, fixed with screws installed obliquely. One of the ends of the additional plank can be processed. This is necessary if the clypeus can be displaced.

It is not very convenient to mount this type of extensions. You have to think about how not to split the bar, about how to close the caps of the screws. However, it is not necessary to select according to the shape of the grooves / protrusions, which is far from simple and binds only to one manufacturer.

The telescopic door extension has pre-formed grooves. From the point of view of docking, this is a very convenient option: they drove the protrusion into the groove, tapped until it completely coincided and the whole installation. But only if the match is perfect. What else is a telescopic extension convenient for? A telescopic casing can be installed in it (if it fits).

How to install extensions on an interior door

In this paragraph, we will focus on ordinary slats – with straight ends. They are sold in lengths of 2100-2300 mm. Three strips are needed for one door: One on the right and one on the left, and a piece from the third will go to the top. If you put several doors at the same time and you have them of the same color, one plank will go to the two “tops”.

Planks are usually wider and longer than necessary, so they will have to be trimmed. What tool? With what you have. A juvenile who cuts DMF, chipboard or wood is suitable. To decorate the corners, you may need a miter box (if you are going to join the box (and extensions) at 45 °. It is also convenient to use it to “not fill up” the cut and make it strictly perpendicular.

We take measurements and make blanks

Before installing extensions on an interior door, you need to find out the exact dimensions of the expansion bars. To do this, we install a door frame in the doorway, fix it. Draw an opening on the plan, it will be easier to write the dimensions. Next, take a tape measure and a level, measure the size of the extensions that you need.

• The width of the extension is determined as follows: we insert the measuring tape of the tape measure into the groove until it stops. We apply a level to the wall, at the intersection with the roulette tape we determine the required width. Measurements are carried out at six points: two on each side. If the wall has an unequal thickness, we take the width of the extension according to the largest figure.
  

• Trim length. Again we take a tape measure, measure along the opening – from the floor (threshold, who has it) to the beginning of the groove in the box of the installed door. We measure on the right and on the left, because again there may be a difference. We measure the upper part from the beginning of the box to its end (not from the groove).

Now, in size, we cut out those that we need from standard planks. Make marks with a pencil – on light strips a simple pencil is clearly visible, on dark ones you can take a white one. We try on the cut-out strips in the opening, if necessary, cut them a little.

We collect

Before you put the extensions on the interior door, they must be connected to each other. We lay out the cut-out additional strips on the floor in the form of the letter “P”. If they have a finished edge, lay them out so that the edge is on one side. Planks will need to be connected to each other. If they are made of MDF or chipboard, you must pre-drill holes in the top bar.

To do this, it is better to take a square (ideally, a carpenter’s square, but an ordinary school one will do). On the bar we draw a line that marks the middle of the thickness of the bar. If the board thickness is 10 mm, the line runs 5 mm from the edge. If the bar is 15 mm thick – at a distance of 7,5 mm. We put two points on this line, and then we drill holes. Diameter – 1 mm less than the diameter of the screws.

Next, the holes must be transferred to long strips. To do this, we join them, align the edges. Using a drill, we transfer the marks to the end of the bar, then deepen it to the required length (along the length of the self-tapping screw). Having made holes, we join the strips, we twist the fasteners. The addition to the interior door is half assembled. But do not rush to attach the second bar. It is necessary to try on the already assembled “in place”.

We put the assembled L-shaped part in place, driving the planks into the groove in the door frame. The upper jumper turned out to be larger (we measured it this way). We take a pencil, put a mark where the groove begins. Try to be precise as this is important. The excess can not be cut off. Just draw a line along the mark and make marks on it, then drill holes. After assembly, the letter “P” is obtained. We have assembled the trim for the interior door, now we need to install and fix it.

Door frame installation

Now the plugin can be installed. Check opening first. If the doors were placed on the foam, it can block the groove. We cut off the excess so that the slats go in freely. We insert the U-shaped structure into the groove, tapping the butt with the palm of your hand. We start at the top, then on the sides.

We take masking tape, we fix the strips to the walls with it. If in some places the extension to the interior door does not fit snugly against the box (there is a gap), we remove this gap with the help of linings. To do this, you can use mounting wedges. If they are not, make from foam. You just need to set the bar evenly, for this purpose dense foam is enough.

Attachment box

It is also necessary to align the addition to the interior door to the level. You should not focus “by eye”, use the level. Using a level and wedges, we remove all protrusions and blockages. In the process, we fix the aligned areas with masking tape. The distance between the tacks is 40-50 cm. One at the top and bottom (receding about 10 cm), and further at regular intervals.

Next, using low expansion mounting foam, fill it with the space between the wall and the additional plank. Read the instructions on the container before use. It may be better to moisten the surfaces. In any case, it is necessary to lay the mounting foam in stages, otherwise it may bend the extension strips. We’ll have to tear it all off, clean it and foam it all over again.

So, first we apply foam deep into the gap. A little, one lane. In parallel, we make strips for the entire width near the “tacks” (an example of applying foam to the door extension in the photo above on the right). The foam in the tack area will give the bar stability, the strip in the far part – near the joint – will press the extension to the groove, but at the same time it will not bend the bar.

We leave the foam on the side rails to polymerize, but for now we are engaged in filling the gap from above. If it is as big as in the photo, there is no point in transferring a lot of foam. It’s easier to cut a “bookmark” out of foam, put a wooden block of a suitable size. In size, it is slightly smaller than the free space. A gap of at least 1 cm should remain on all sides. But too large gaps are not needed.

Next, proceed as follows:

• Place small pieces of foam plastic 1 cm thick or so under the embedded part.
• We apply a snake layer of foam on the back wall (if any).
• We put a mortgage bar, fill the cracks around the perimeter with foam. Again, not too much, so that the foam extension bar does not bend down.
• If there is a need, we put the “front” bar (in the photo above, the left bottom). If the bar is wide enough, skip this step.
• We align the position of the additional plank with the help of a building level, fix it with masking tape.

After the first layer of foam has hardened (the time is indicated on the bottle), we fill the rest of the space. If the extension on the interior door has a significant width, it is possible (and better) to apply the foam in two stages. But each time you have to wait for the polymerization time. After that, it remains only to install the platbands.

How to attach an extension to the door frame if it is thicker than the selected quarter

Often the extension is thicker than the quarter selected in the box. What to do then? How to make it so that the extension rests without cracks and holds firmly? There is a simple way – to drill holes obliquely, screw in the screws, then close the holes with matching plugs. Here everything is more or less clear, but not very beautiful – the stubs are still visible.

There is another way. Need hangers for drywall. Only they should be the strongest and thickest. From the hangers we separate the parts of the tape with perforation. Each makes two parts. You will also need small self-tapping screws (fleas). We fasten the perforated tapes to the door frame along the perimeter – at the corners, stepping back 10-15 cm, also from below, and in height at a distance of 40-50 cm.

Screw the screws backing 1,5-2 cm from the edge of the box (middle photo). One self-tapping screw per piece of metal tape is enough. When the door frame is installed, the tape will stick out. These slats are thin, so even the smallest gap will not be a problem. If the extension on the interior door is the same width, just insert it. Plates due to elasticity press it tightly.

If the extension is wider, first we bend them to the front, then return them back. Due to the fact that they are not fixed to the edge, they are bent, becoming like an arc.

Now we insert additional strips, leading them between the plates and the groove. They will press the bar tightly. The cracks will not be visible even upon closer inspection.