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How to install extensions on interior doors: step-by-step instructions, expert advice, necessary materials and tools. How to fix the extension to the box Options for installing extensions on interior doors

Dobory, or doborny boards, are installed in the frame of the door, if the width of the door frame (jamb, "loot") is less than the thickness of the wall in which the door is installed. Extensions play not only an aesthetic role, covering uneven and easily soiled slopes. (if you are interested in other ways of finishing slopes - read about them here). They, together with the platbands, also strengthen the door and prevent it from warping. Do-it-yourself installation of extensions is possible both when installing a new door, and on an existing door. We will look at the most common cases.

Additional boards can be made independently, from a flat board, edged or tongue-and-groove, for thick walls. Waterproof plywood BS (aircraft plywood), pasted over with a decorative self-adhesive film, is very well suited for very thick or damp walls or backing pads: BS plywood does not delaminate and does not crack during fine processing of edges and does not warp from moisture.

Door frame with extensions. The mustard color indicates the lining.

However, most often it turns out to be cheaper and easier to use ready-made MDF boards with decorative coating. The standard dimensions of factory-made extensions are in the range of 80 - 550 mm. For cases when it is necessary to make type-setting extensions on thick walls, extensions from MDF with a tongue-and-groove lock are produced.

According to standard technology, extensions are installed in a special recess on the inside of the door frame - a quarter. However, when installing extensions on an already standing door, it is permissible to use extensions (adjacent to the door frame) and lining (slipped under it).

Attached extensions are recommended to be used only in dry rooms with moderate temperatures and in cases where the door is made of very high quality or may lose value from alteration (for example, if the door is an antique or a museum piece).

If the door is slanted

If the door jamb is skewed and the deviation of the upper bar from the horizontal is more than 5% of its length, and the door leaf is fitted to the slanting frame, the installation of extensions without altering the door is not recommended. The door frame itself does not warp; its skew indicates structural defects, without correcting which the extensions will not immediately give a look, and subsequently they will warp and split.

Tools and accessories

To install the door extensions, you will need some additional tools: a manual wood milling machine, a manual circular (parquet) saw and a clamp with soft sheathing of the bed. The clamp is most needed in order to press the saw against the stool with the disc up, to get a convenient mini-circular. It is possible to tighten the clamp with a soft one by successively putting on it and heating over a gas burner at a distance of 0.4 - 0.5 m, a heat-shrinkable tube in 3-4 layers.

Of the accessories, you will need 3-4 stools of the same height and not staggering, 4-5 wooden planks of approximately 30x30 or 40x40 mm, with a dozen wedges from the same rail and several strips (you can waste) of ordinary packaging plywood or drywall.

Door installation process

Base plane picking

In prepared for the installation of add-ons doorway you need to immediately beat off the base plane, and mark its trace on the floor with a pencil. This is exactly done using the Pythagorean triangle method (a right-angled triangle with an aspect ratio of 3:4:5; a "magic triangle"). We will give explanations to the figure on how to do this:

Half the width of the doorway along the bottom is considered equal to three base lengths - 3l. If, for example, the width of the opening is 60 cm, then its half is 30 cm, and the base length (l) is 10 cm.
From the corners of the opening with a cord 5l long, we make two marks. From their intersection at point B to point O (middle of the opening) should be 4l. In this case, the OB line will be exactly perpendicular to the opening plane, and all horizontal measurements can be taken from it; the desired vertical accuracy will give a plumb line.

Note: if you have the opportunity to use the laser projector of the base surfaces, then the described procedure is not needed. But it will not be possible to achieve the required accuracy with the help of a carpenter's or locksmith's large square: the error will be greater than the gap between the door leaf and door frame.

What to do if the walls are sloping

When checking the verticality of the walls, it may turn out that they are sloped, positive or negative. If the slope does not exceed 5 mm along the height of the door, it can be reduced to zero on the surface under the casing with plaster. If it’s more, there’s nothing to be done, when cutting additional boards to size, you will also have to cut them into a wedge.

Foam blowing

After installing the extensions, the slots are blown out with mounting foam before plastering. The foam expands as it solidifies and creates a fairly significant pressure. To prevent the finished door jamb from this, you must follow the following rules:

Do not remove the leveling wedges until the foam has completely cured.
Also, do not remove the spacer bars; if they were not previously needed - install on friction, but not tight. The spacers should support the extensions, not push them apart.
Do foam blowing with uniform movement around the perimeter in 3-4 steps; each subsequent - after the complete solidification of the previous one.
There should be some space left from the outer edge of the foam to the edge of the slope. If you see the next layer of foam coming out, stop blowing. "Re-plastering" later is better than "re-plastering" now.

Immediately with the box

The most technologically simple case is to install door extensions with your own hands when installing a new door along with the door frame. Such an operation is performed in the following order:

On the stools we lay the door jamb with the inner (opposite to the hinges) side up.
We align the corners to rectangularity, checking with diagonals: they must be of equal length. To do this, we temporarily nail a wooden plank to the bottom with small nails equal to the length of the upper plank of the door.
If the jamb is without a quarter for dobors, we select a quarter with a milling machine. The depth of the quarter should be equal to the thickness of the additional board, and its width should be equal to the depth.

Example: additional board - 16 mm thick (standard MDF thickness). You need to choose a quarter 16X16 mm.

Along the perimeter of the door frame, we attach strips of plywood or drywall to the outside so that they protrude up the width of the additional board. Solid framing is not needed, two trims are enough for the top bar and 3-4 for the sidewalls. We nail plywood with carnations; drywall will have to be fixed with self-tapping screws.
We cut the extensions to size. The top bar of the extension should lie between the side ones, so we cut it to the size of the upper quarter, and the side ones to the size of the sidewalls of the box.
On both sides of the quarter we apply liquid nails or any mounting glue for wood.
We insert the additional boards into place and wait for the glue to set.
We remove the temporary lower bar that kept the extensions from falling out of the plywood and put the door frame in place.
Align the box to the base plane.
We align the box in width with the help of wooden slats-spacers; while checking the verticality of the sidewalls with a plumb line.
Knocking wedges under the sidewalls, we achieve the horizontality of the upper bar of the door.
We blow out the cracks with foam and plaster flush with the surface of the wall.
We nail the skirting boards, cut them to size and glue the trim with liquid nails - the door with the extensions is ready.

Finished door and straight slopes

In this case, in order to facilitate the installation of extensions, you need to prepare in advance a dozen and a half or two thin, 3-4 mm thick, wedges from waste plywood. After that:

We knock down the plaster from the slopes and check if there is a quarter on the door frame. If yes, then it remains to choose additional boards in thickness.
We cut the extensions to size, but not as described above: the top board will now fit the size of the box on top; lateral - in the size of the lateral quarters.
We apply liquid nails to the inner edge of the side extensions, insert them into place. If you can reach a quarter, it is better to apply glue to it.
We adjust the height of the dobors with wedges from below, as described.
We insert in turn the spacer strips, pre-cut to the width of the doorway, and we support the extensions from the side of the slope with thin wedges so that they do not fall out. We check the verticality of the extensions with a plumb line; better - just two, suspended in advance.
We apply glue not to the tops of the side extensions, to the inner edge of the upper extension board (or a quarter), and lay the upper extension board.
After the glue has hardened, blow it with foam and decorate as described.

If there is no quarter and with inclined walls

If the door frame is without a quarter, then there are two options:

Reverse quarter. With a milling machine, we remove a quarter on the extensions, 10-15 mm wide and half the thickness of the extension. With “not very” inclined walls, this option is convenient in that a quarter on the extension can be made oblique in width, and such an extension will hold no worse than “normal”.
If the walls are brick, then you can knock out a groove in the slope under the door frame, and put underlays. This option is convenient for those who do rough work with a lot of effort better than light, but thin.

In both cases, the extensions are installed with the help of auxiliary thin wedges, as already described.

slope slopes

If the slopes of the doorway with a slope (expanding opening), then, regardless of whether new door or an existing one, the extensions must be placed at the standing door. The fact is that when installing direct extensions, you get a very wide gap. After blowing foam behind the casing, there will be a space where the plaster lies on the foam. Sooner or later cracks and/or dips form there.

Therefore, before installing extensions in openings with inclined slopes, the inner edge of the extensions must be brought to a wedge along the length, as marked in the figure with a red circle. After trimming to size, the extensions themselves will take the form of a trapezoid. Otherwise, the installation of extensions in this case has no special features.

Interior doors

As a rule, extensions are installed on the side opposite to the door hinges. But when installing the extensions of interior doors, it is possible that they will have to be installed from the side of the hinges. If so, then you first need to check whether the extensions interfere with the opening of the door.

If with a fully open door between its edge and the edge of the door frame there is a gap equal to the thickness of the extension with a margin of 2-3 mm, there is no problem: we put the extensions in any of the ways described above. If the edge of the door is adjacent to the edge of the box, you need to put underlays, having previously knocked down the plaster from the slopes. This should not be neglected: only 1.5 mm of “pressing” the sash to the extension eats up 10 degrees of its opening angle, not to mention the fact that the extension will soon be damaged.

Read about the full cycle of interior door installation here.

steel doors

It is possible to install extensions on steel doors only with lining ones. There is a nuance here: along the length of the extensions, along their inner DECORATIVE side, at a distance of 10-12 mm from the edge, you need to use a circular saw to select a groove with a depth of a third of the thickness of the extension and a width in the thickness of the corner from which the door frame is welded plus 1 mm. It is for this groove, when the edge of the steel door frame enters it, the box will keep the extension with it.

More information about the installation nuance entrance doors can be found at the link.

Type-setting extensions

When cladding walls MDF panels, laminate, etc. The selection of the door frame can be done in typesetting from pieces of sheathing material, longitudinal or transverse. But technologically, such an operation already refers to the technology of wall cladding, and not the installation of extensions.

Video: full installation cycle of an interior door

Each interior door after installation needs a finishing touch - extensions. This element allows you to give the design a complete look. Dobors are boards that frame the door leaf. They close the gaps that remain after the installation of the door. Even a novice master can install them. To do this, you need to consider the interior doors. Detailed instructions will be provided below.

Why are supplements needed?

Many novice masters are interested in how to install an extension on the interior door "Tanganyika", "Terra", "Modern Nika" and other popular models. This is an easy procedure. However, you should be aware of some of the nuances of doing this work.

Why are supplements needed at all? These are decorative boards that frame the door leaf. Two of them are vertical and one is horizontal. They are designed to increase the space that the door frame can cover. It becomes larger, so all the flaws made during the installation of the door become invisible.

Extras are created from different materials. It can be natural wood, MDF, chipboard. Sometimes door manufacturers supply slats along with the door leaf. However, sometimes they are purchased separately. Planks can be of different widths. In a room with thin walls, thin extensions will be appropriate, and in a room with thick partitions, wide ones. This indicator can vary from 8 to 55 cm.

Varieties

There are several types of extensions. They may be without edges. In this case, the ends of the board will not be protected by a layer of decorative film. A simple edging with an edge is protected by a special layer on all sides. There are also telescopic extensions. In their ends there are special grooves with which fixation is made.

The first two types of extensions are straight planks. They have straight cuts. Experts recommend installing extensions with an edge. Such products allow you to close the entire cut. In this case, the door will look nice and neat. If you choose extensions without an edge, there is a chance that they will not completely close the cut.

Many owners are interested in how to install telescopic extensions on interior doors. This is a more modern type of boards. They have a groove with which a tight fastening is made, which does not require the use of additional materials. The dobor is connected to the door frame or platbands without glue.

Installation methods

Do-it-yourself installation of dobors on interior doors can be done in different ways. The design forms the letter "P". It can be attached in a variety of ways. You can fix the boards directly to the door frame or to the wall in the opening area. You can also install the strips on the mounting beam, which is located between the vertical sections of the opening and the extensions.

It should be noted that during operation, a high load will not act on the slats. Nevertheless, in order for the extensions to be firmly fixed in place, glue is often used. However, experts advise using self-tapping screws for these purposes.

Fixation with hardware is made from the front side. Therefore, it is important to deepen their hats. So the fastener will not be visible, will not interfere with the opening and closing of the door leaf. On top of the hats, you need to close them with special plugs to match the extensions or cover them with mastic.

Preparatory work

Having figured out what extensions are, you can choose the best option for your door. It is necessary to determine which option the manufacturer provided for a particular model. It should be noted that the installation of telescopic extensions on interior doors is not always possible. We need grooves in which it will be possible to install the strips.

After choosing the type of extensions, you need to calculate the dimensions for each side. It is especially important to pay attention to their width. Subsequently, it will be impossible to correct this characteristic. Removing the length of the extensions is quite simple.

Next, you need to prepare the surface for installation. Excess foam must be cut off with a knife. Also, all contaminants must be removed from the surface of the base. Otherwise, distortions may appear. Proper preparation surface allows for good adhesion of extensions to it. After that, you can proceed directly to the installation.

What else to consider before installation?

When studying the technology of how to install interior doors yourself with an extension, you should pay attention to the installation of decorative strips. Often beginners make mistakes in the course of such work. Having installed a box for an interior door, they may notice a significant skew. In this case, the addition will not help. You need to pay attention to correction.

If the deviation of the upper bar in the horizontal plane is more than 5% of the total length, it will not be possible to install the extensions correctly. Of course, the master can fit the canvas to such a box. However, the presence of such a defect indicates serious errors made during installation.

To eliminate them, you will need to dismantle the entire structure. It is necessary to find out what exactly led to such a violation. Only by eliminating the error, it will be possible to install extensions. Otherwise, they will not improve the appearance of the door immediately after installation. During operation, they crack and deform. To prevent this situation, you need to pay attention to the exact installation of the structure.

Tools and materials

To perform all the manipulations quickly and correctly, you need to prepare a manual milling machine designed for woodworking. Be sure to prepare a manual parquet (circular) saw. In the course of work, a clamp is required. She should have a soft lining on the bed.

If there is no such material on the instrument, it is quite possible to fit it yourself. This will require several heat shrink tubing. They are put on the tool and heated over a gas burner. It is necessary to keep the material at a distance from the flame of about 40-50 cm (not closer). Such tubes should be put on the clamp in 3 or more layers.

You will also need stools of the same height. They shouldn't wobble. Several wooden planks should be prepared. Their cross section can be 30x30 or 40x40. Several wedges are cut from the same rail. You will also need a few strips of packing plywood. Drywall strips will also work.

Beginning of work

To install extensions for interior doors with your own hands, you need to follow the advice of experts. The opening prepared for installation must be properly marked. This procedure is called retraction. To do this, you need to use the Pythagorean formula. According to his theorem, in a right triangle, as everyone knows from school, the sides are related as follows: 3x4x5.

It should be noted half the width of the opening. At the bottom, this segment is equal to 3. For example, the width of the opening is 70 cm. Half of it will be 35 cm. The base length is 11.6 cm. You need to make marks with a cord, starting from the corners. Each of them should be 5.83 cm from each corner. From the intersection of these points to the middle of the width there should be a distance equal to 4 shares. This line will be perpendicular to the plane of the box.

From this line, all further horizontal measurements can be taken. The vertical plane of the opening can be checked with a plumb line. If you do not want to carry out such calculations, you should use laser level. This is an accurate device that will allow you to perform all measurements correctly.

What not to do

Considering how to install extensions on interior doors, you should pay attention to some mistakes that beginners make.

Professional builders argue that it is impossible to use a carpenter's triangle during the measurement. The error will be large. Therefore, the gap between the door frame and the leaf can be large. It is better to use a calculation system or a laser level.

uneven walls

Installing extensions on interior doors requires accurate measurements. In typical apartments, and even in private houses, it is not uncommon for the walls in the room to be sloped, uneven. If the indicator does not deviate by more than 5 mm over the entire height of the door, this situation does not need to be corrected.

However, it often happens that the deviation at different points of the opening is greater. In this case, when cutting additional boards, this feature will need to be taken into account. In this case, they are cut into a wedge.

Self-tapping installation

How to install extensions on interior doors? Most often, the owners of apartments and houses use self-tapping screws during this work. This is a reliable way to fix. If the slats are not telescopic (they do not have grooves), start the installation from the top slat. You need to measure its length and cut off the excess. Having attached the board to the wall, you need to check everything again. Then you can screw it to the wall.

After that, you can install the side boards. They are customized to size. For each side of the opening, the length of the side strips may vary. Next, holes for self-tapping screws are drilled in the slats. Attach a bar to the wall and screw it to the wall.

After that, you need to seal the joints. Hats deepen into the material. To do this, the holes are closed with plastic plugs. You can also just pick up a sealant to match the extensions. They cover all the holes in the boards.

telescopic dobor

How to properly install telescopic extensions on the interior door? This is a fairly simple procedure. Even if there are small errors, they can be masked. Telescopic slats allow you to do this. In this case, the installation procedure will take a minimum amount of time. The installation of telescopic extensions requires a minimum number of tools.

First, the wall surfaces are prepared accordingly. After that, the strips are applied to the surface, once again checking the correctness of the measurements. The installation of the telescopic dobor also begins with the top bar. After that, the length of the sidewalls is measured. The excess is cut off.

The groove is inserted into the lock to such a depth that the bar can completely cover the wall. With help rubber mallet you need to lightly tap on the joint surface. So the keys will be better fixed. If the groove and spike do not fit snugly against each other, they stagger, you need to use glue in your work. To do this, get liquid nails. After the extensions are installed, it will be possible to proceed with the installation of platbands.

Application of glue

Installation of extensions on interior doors can be done without self-tapping screws or tongue-and-groove joints. In this case, the strips are fixed with glue. This is a fast procedure. The outer side of the extensions remains intact. This is especially important when installing MDF planks. When drilling holes, the top decorative layer may crack. In this case, the appearance of the add-on will be spoiled.

To avoid such troubles, you need to clean the opening from debris, foam, etc. Next, special glue is applied to the back surface of the plank. The plank is applied to the base. Then you need to wait until the composition dries. This option is pretty simple. However, the base must be level. Otherwise, over time, in some places, the extension will peel off the surface.

Having considered how to install extensions on interior doors, you can perform all the steps yourself. Quality finished work will be high if the calculations are carried out very accurately. A large error can lead to serious design defects.

Dobory, or doborny boards, are installed in the frame of the door, if the width of the door frame (jamb, "loot") is less than the thickness of the wall in which the door is installed. Extensions play not only an aesthetic role, covering uneven and easily soiled slopes. (if you are interested in other ways of finishing slopes -). They, together with the platbands, also strengthen the door and prevent it from warping. Do-it-yourself installation of extensions is possible both when installing a new door, and on an existing door. We will look at the most common cases.

However, most often it turns out to be cheaper and easier to use ready-made additional boards made of MDF with a decorative coating. The standard dimensions of factory-made extensions are in the range of 80 - 550 mm. For cases when it is necessary to make type-setting extensions on thick walls, extensions from MDF with a tongue-and-groove lock are produced.

If the door is slanted

Tools and accessories

Door installation process

Base plane picking

In the doorway prepared for the installation of the extensions, you must immediately beat off the base plane, and mark its trace on the floor with a pencil. This is exactly done using the Pythagorean triangle method (a right-angled triangle with an aspect ratio of 3:4:5; a "magic triangle"). We will give explanations to the figure on how to do this:

Half the width of the doorway along the bottom is considered equal to three base lengths - 3l. If, for example, the width of the opening is 60 cm, then its half is 30 cm, and the base length (l) is 10 cm.
From the corners of the opening with a cord 5l long, we make two marks. From their intersection at point B to point O (middle of the opening) should be 4l. In this case, the OB line will be exactly perpendicular to the opening plane, and all horizontal measurements can be taken from it; the desired vertical accuracy will give a plumb line.

Note: if you have the opportunity to use the laser projector of the base surfaces, then the described procedure is not needed. But it will not be possible to achieve the required accuracy with the help of a carpenter's or locksmith's large square: the error will be greater than the gap between the door leaf and the door frame.

What to do if the walls are sloping

Foam blowing

Do not remove the leveling wedges until the foam has completely cured.
Also, do not remove the spacer bars; if they were not previously needed - install on friction, but not tight. The spacers should support the extensions, not push them apart.
Do foam blowing with uniform movement around the perimeter in 3-4 steps; each subsequent - after the complete solidification of the previous one.
There should be some space left from the outer edge of the foam to the edge of the slope. If you see the next layer of foam coming out, stop blowing. "Re-plastering" later is better than "re-plastering" now.

Immediately with the box

The most technologically simple case is to install door extensions with your own hands when installing a new door along with the door frame. Such an operation is performed in the following order:

On the stools we lay the door jamb with the inner (opposite to the hinges) side up.
We align the corners to rectangularity, checking with diagonals: they must be of equal length. To do this, we temporarily nail a wooden plank to the bottom with small nails equal to the length of the upper plank of the door.
If the jamb is without a quarter for dobors, we select a quarter with a milling machine. The depth of the quarter should be equal to the thickness of the additional board, and its width should be equal to the depth.

Example: additional board - 16 mm thick (standard MDF thickness). You need to choose a quarter 16X16 mm.

Along the perimeter of the door frame, we attach strips of plywood or drywall to the outside so that they protrude up the width of the additional board. Solid framing is not needed, two trims are enough for the top bar and 3-4 for the sidewalls. We nail plywood with carnations; drywall will have to be fixed with self-tapping screws.
We cut the extensions to size. The top bar of the extension should lie between the side ones, so we cut it to the size of the upper quarter, and the side ones to the size of the sidewalls of the box.
On both sides of the quarter we apply liquid nails or any mounting glue for wood.
We insert the additional boards into place and wait for the glue to set.
We remove the temporary lower bar that kept the extensions from falling out of the plywood and put the door frame in place.
Align the box to the base plane.
We align the box in width with the help of wooden slats-spacers; while checking the verticality of the sidewalls with a plumb line.
Knocking wedges under the sidewalls, we achieve the horizontality of the upper bar of the door.
We blow out the cracks with foam and plaster flush with the surface of the wall.
We nail the skirting boards, cut them to size and glue the trim with liquid nails - the door with the extensions is ready.

Finished door and straight slopes

In this case, in order to facilitate the installation of extensions, you need to prepare in advance a dozen and a half or two thin, 3-4 mm thick, wedges from waste plywood. After that:

We knock down the plaster from the slopes and check if there is a quarter on the door frame. If yes, then it remains to choose additional boards in thickness.
We cut the extensions to size, but not as described above: the top board will now fit the size of the box on top; lateral - in the size of the lateral quarters.
We apply liquid nails to the inner edge of the side extensions, insert them into place. If you can reach a quarter, it is better to apply glue to it.
We adjust the height of the dobors with wedges from below, as described.
We insert in turn the spacer strips, pre-cut to the width of the doorway, and we support the extensions from the side of the slope with thin wedges so that they do not fall out. We check the verticality of the extensions with a plumb line; better - just two, suspended in advance.
We apply glue not to the tops of the side extensions, to the inner edge of the upper extension board (or a quarter), and lay the upper extension board.
After the glue has hardened, blow it with foam and decorate as described.

If there is no quarter and with inclined walls

If the door frame is without a quarter, then there are two options:

Reverse quarter. With a milling machine, we remove a quarter on the extensions, 10-15 mm wide and half the thickness of the extension. With “not very” inclined walls, this option is convenient in that a quarter on the extension can be made oblique in width, and such an extension will hold no worse than “normal”.
If the walls are brick, then you can knock out a groove in the slope under the door frame, and put underlays. This option is convenient for those who do rough work with a lot of effort better than light, but thin.

In both cases, the extensions are installed with the help of auxiliary thin wedges, as already described.

slope slopes

If the slopes of the doorway are with a slope (expanding opening), then, regardless of whether the door is new or an existing one, extensions must be placed next to the standing door. The fact is that when installing direct extensions, you get a very wide gap. After blowing foam behind the casing, there will be a space where the plaster lies on the foam. Sooner or later cracks and/or dips form there.

Interior doors

steel doors

Installing doors is a responsible, but fairly easy process. How to install an interior door in an apartment with your own hands is described below.

Do-it-yourself installation of interior doors: step by step instructions

The interior door is formed by:

box or frame - a supporting structural element;
door leaf - the main part of the door, its "face";
platbands - decorative elements that mask the joints of the frame with the wall.

Doors may also include:

threshold,
add-on elements.

The doorway, as a rule, has a width of 70, 80 or 90 cm. The door leaf is selected 10 cm narrower - its width can be 60, 70 or 80 cm.

Interior doors installed at the entrance to rooms such as kitchens, toilets and bathrooms often have a threshold. If the door is assembled without a threshold, a gap of 1-2 cm is left between the floor and the bottom of the canvas.

Additional elements - are used in cases where the thickness of the wall exceeds the thickness of the box. Their purpose is to improve appearance designs.

In the general case, do-it-yourself installation of an interior door is done as follows:

The frame is assembled and installed.
The canvas is hung.
Addition is installed.
Platbands are mounted.

Guide to action

To install one interior door, you will need:

mounting foam balloon;
bar 40x40 for wedges and spacers;
self-tapping screws;
building level;
tape measure, pencil;
hacksaw or jigsaw;
cutting saw.

Assembly and installation of the box

The assembly and installation of the frame is performed in the following sequence:

Trimming racks - the height of the box is reduced in accordance with the size of the gap.
Assembly - structural elements are connected into one whole (self-tapping screws are used).
Preliminary fixation of the door frame - the upper and then the lower parts of the structure are fixed in the opening with wedges, a spacer is installed at the level of the lower wedges.

Installation of the canvas and final fixation in the opening

The sequence of work of this stage:

Hanging the canvas - the canvas is connected to the frame from the side of the loops.
Checking the operation of the door - the door is opened and closed several times, checking the smoothness of its course.
Installation of additional wedges - wedges are installed at the level of the upper hinge and slightly below the level of the handle.
The final fixation of the box - the gap between the frame and the opening is filled with mounting foam.
Dismantling the wedges and trimming the protruding foam - after the foam has dried (one day after foaming), the wedges are removed or cut off and the excess foam is cut off.

Installing the addition of interior doors with your own hands is done as follows:

The width of the area to be cut is measured.
The trim strip is cut to the desired width.
The dobor is inserted into the groove and foamed.

Important: if the width of the extension does not cover the entire width of the opening, two such elements and a connecting strip are used.

Installation of platbands

The order of work on the installation of platbands is as follows:

The length of the elements is determined.
The ends of the elements are cut at an angle of 45 degrees.
The platbands are fixed in place with glue or nails.

As you can see, installing an interior door with your own hands is not so difficult. The main thing is to follow the instructions and be careful.

P.S. And for dessert, I suggest watching a video clip: Installing interior doors with your own hands

The installation of the door leaf often involves the design of slopes in order to decorate and level them. The best solution to this problem are extensions that are installed on the wall near the box. These structures are small planks of wood or plastic. Before installing such products, you should find out the features of installing extensions on the door. This will simplify and speed up all installation operations.

The need for extras: the pros and cons

Dobors are small planks or boards that are attached to the slopes. They are used only on openings that have a significant width, and the box itself is not able to close them. Technically, these elements are not mandatory attributes entrance or interior doors. You can do fine without them, but at the same time you will need to form a wide slope, which is not always convenient and practical.

Door extensions have several advantages over other finishing methods:

Possibility of installation on an uneven surface. Therefore, extensions exclude additional wall decoration, which reduces the cost of materials.
High-quality protection against pollution.
High mechanical strength. This is especially true for products made of natural wood, from which extensions are most often made.
The strips installed on the slopes additionally strengthen the door frame, preventing it from loosening or warping.
Versatility. Dobors today are produced in various thicknesses and widths, which allows them to be used for finishing almost any type of slopes. This is especially true of telescopic models that can be sewn together like a wooden lining.
Variety of designs. Structures are made from various materials, which are designed for certain style directions.

Mounting methods

Installing door dobors involves fixing them to the wall. This process is relatively simple and can be done in several basic ways:

Fastening directly when installing the door frame. In this case, the additional board is attached directly to the door frame. Various methods can be used for this. by the most simple option is to knock them together with the help of an inner board that is attached to the extension and the box. It is important during installation to align the planes of both elements in order to obtain a flat surface. But if the slopes have significant drops, then without certain skills it will be difficult to fit the elements very evenly with minimal damage.

To hide the joint between the box and the dobor, a thorn-groove type connection is cut out at their ends. In this case, the board goes inside door frame, which hides it under itself. This option is more common, as it allows you to get a beautiful and decorative surface.

Similar grooves today are complemented by the extensions themselves at each of the ends. This allows you to combine them into a more aesthetic system. But for metal doors it is impossible to make such a connection after installing the box. This is due to the fact that it is technically unrealistic to form a groove in the metal using a milling cutter.

How to do it yourself?

Dobors are ordinary planks or boards that perform a decorative function. Therefore, you can make them yourself from various materials. Often they are formed from natural boards of small thickness or sheet products (chipboard, plywood, etc.).

The process of making dobor at home can be divided into several successive stages:

Initially, measurements of the opening are carried out. It is important to measure the slopes in different places in order to eliminate inaccuracies in dimensions. This procedure must be carried out for each side of the slope separately.
Based on the data obtained, a blank should be made. To do this, the dimensions of the future addition are applied to the board. Please note that it is best to provide a small margin so that no gaps form at the joints after installation. When the markup is ready, the board is cut into extensions. It is better to perform such operations with a circular saw, as it will provide a more even and high-quality cut.
The procedure is completed with fitting and trimming. If the board is slightly larger, then you should align the ends with an electric planer. To give the extension a unique design, the wood must be sanded and painted with stain or varnish. If laminated chipboard is used, then you need to take care of closing the ends with special tapes. They are glued to the material with an iron or a special hair dryer.

The manufacture of extensions allows not only to save money, but also to get a durable system that will be adapted to specific operating conditions.

How to install correctly?

Installation of door extensions is a simple operation, which, if desired, can be performed independently. But before installing such elements, it is advisable to read the instructions for their fastening. This will allow you to deliver them much faster and better.

Required Tools

Installation of extensions is an operation that requires a minimum amount of skills. But to get a quality result, you should use an auxiliary tool, including:

Hand or circular saw. The best option would be a grinder with a special circle for wood or a jigsaw. It is advisable to use saws with small teeth to get a smooth joint without burrs.
Milling machine. With its help, grooves are formed for joining the box and the additional board. Please note that installation can be carried out without this operation. But it is impossible to get accurate and inconspicuous ends without it.
Clamps. These mechanisms are used to fix the grinder to the chair. This will allow you to get a mini circular saw that will make it easier to trim the extension in the right place.
Pencil and a long line.

To optimize the work, you will also need a long table or several stools. They are used as supports on which boards are laid during processing.

How to count?

Installation of extensions always begins with measuring the thickness of the wall. The choice of the type and quantity of consumables depends on this parameter.

Initially, you need to get the width of the free space on the wall near the box. Measurements are taken with a ruler or a corner. The latter option is more accurate, since it is necessary to take into account the angle between the door frame and the board. It is desirable to know the width around the entire perimeter of the opening.
The next step is to measure the thickness of the door frame. This is necessary in order to select the appropriate extension, under which the minimum number of supporting elements will need to be placed.
The procedure ends with the calculation of the number of additions. This takes into account not only the width of the board and the opening, but also their height. It is advisable to take these parameters with a small margin, so that you can then adjust the canvas to the dimensions of the opening. Please note that all extensions on the market have standard sizes. Therefore, when choosing, focus on them.

What can be used instead of supplements?

Dobors are factory-type products that are produced with certain technical parameters. But no one bothers to replace finished products with improvised materials that every owner can find:

Solid board. The best option for making dobor. The material perfectly withstands high loads, and is also strong and durable. In this case, it is possible to use various types of wood for the manufacture of the structure. This will allow you to adapt the final product to the style of the frame and door leaf.
MDF. Products made from wood shavings that are used to make doors. Sheets of this material are also great for extensions. But the substance resists moisture very poorly, so such elements can only be installed indoors with minimal humidity.
Chipboard and fiberboard. Sheets from wood waste, which can be adapted for extensions. Working with them is quite easy, but at the same time they are also afraid of moisture, which limits their use.
Plywood. There are several types of such a substance that is moisture resistant. Plywood is the best option for the manufacture of extensions, as it has an optimal price-quality ratio.

If you do not have these materials, you can make an addition from scraps of plastic lining. Although it is not so strong, it is very easy to cut and is not afraid of moisture.

How to increase?

There are situations when the width of one standard extension is not enough to close the doorway. The solution to this problem is only the extension of the canvas.

This process consists of several successive steps:

Initially, additional boards are installed near the box itself. It is important to fix them qualitatively and evenly.
After that, a second row of material is applied to them, which will already protrude slightly beyond the edge of the wall. This will allow marking along the entire length of the board. An alternative option is to measure an unclosed piece of slope with the subsequent transfer of dimensions to a new workpiece.
When the markup is done, you need to saw off the extension. Please note that cutting is only done from the side that does not fit with the previous board. This is important when telescopic types of coatings are used for building, as they are initially equipped with grooved joints.

When direct extensions are applied, the side of their trimming does not matter. The main thing is that when docking they form a minimum gap.

Mounting

The algorithm for installing extensions consists of the following sequential actions:

Initially, all measurements are taken and the dimensions of all elements are adjusted. It is important that the joints of the boards are with minimal gaps, as this will not only not be beautiful, but will also lead to the formation of drafts.
On the this stage fit the board to the wall. This process involves aligning it in the same plane with the door frame. If the slope is uneven, then for this, wooden planks of various thicknesses are placed under the extension. They should be attached to the wall with screws and dowels.

When the slopes are at an angle, then it is advisable not to align them parallel to the box, but to form them with a slight slope. In this case, the angle should be the same on both sides of the opening.

The procedure ends with the installation and finishing of the extensions. To close the ends, platbands are placed on the outside, which are also made of the same material.