Low base of the house what to do. The height of the plinth from the ground according to standards

The height of the base is one of the parameters that have great value when building a house. This is the lower part of the building, erected on the foundation and performing important functions related to heat retention indoors. The plinth is necessary in order to protect the walls from the effects of groundwater; it prevents the formation of fungus and mold on the walls, and increases the resistance of the building to low temperatures. Thanks to the presence of the base, the heat exchange between the interior and the street increases.

In order for this part of the house to meet all the requirements and contribute to the solution of the assigned tasks, it is necessary during construction not only to choose high-quality and reliable material, but also take into account the height of the basement being built.

How to determine the height of the plinth

The effectiveness of the protective functions performed by the base of a house directly depends on its height and type:

1. The protruding base requires additional finishing and the construction of a canopy that protects the structure from precipitation and moisture accumulation. It becomes a decoration of the facade of any building.
2. The sinking one is the most durable. In this option, the junction of the base and the walls of the house is completely protected from moisture, which guarantees increased safety of the foundation and protection of the waterproofing layer. When constructing this type, there is no need to construct mandatory water outlets.
3. Level with the wall. The least popular type of base. It requires the construction of a canopy, and when additional finishing is carried out it becomes protruding.

The choice of the height of the basement being built is influenced by the type of foundation, the depth of groundwater, and climatic conditions in the area where construction is taking place. In addition, the presence of a basement floor (basement) is important.

When starting work on the construction of a basement, it is worth considering that the higher it is, the less likely it is that interior spaces may be damaged by moisture penetration. Construction begins directly from the foundation of the house, and at the joints with the walls of the building it is required proper organization waterproofing, preventing possible penetration of moisture through the capillaries of the porous material into the walls of the building.

The impact on the base is comprehensive, since it can withstand constant load from the walls. And in cases where the house does not have a basement and the floor is located on the ground, the base is also subject to the pressure of the earth buried inside the entire perimeter of the house.

If, in order to determine the width of the future basement, it is necessary to accurately determine the choice of material from which the walls of the house will be built, and its type depends on the quality of the foundation, then the height will depend on the presence of a basement, temperature regime, weather conditions and the amount of natural precipitation characteristic of the area where construction is taking place. These parameters vary greatly in different areas, so there are no strict guidelines for determining the height of the plinth.

Minimum height

The construction of the base begins directly from the foundation, and it is raised to a height of at least 40 centimeters. It is believed that this is the minimum height of the base of the house.

This height is optimal if there is a strip foundation, although a base of this height is erected on another foundation, based on the decade-average snow level that falls annually in a given area. A basement of this height is erected only in cases where the house does not have a basement.

In some areas, the height of the base of the house is lower than this indicator. In particularly arid zones, the construction of a brick structure is allowed to a height of only 20 centimeters. But even here there is a risk of excessive moisture in the walls of the house when ordinary rainwater gets on them. In most cases, a properly constructed blind area can change the situation. Although, with a low base height, as well as with improper construction of the foundation, the walls of the house may suffer from capillary wetting of the walls with groundwater. This will lead to destruction of the material from the inside and a significant reduction in the life of the building.

Standard height

Ground floor requires a significant increase in the height of the base itself. Now to the main functions that it is designed to perform this design, we also add the provision of installation in the technical room engineering systems, which include pumps or valves. In some cases, when choosing the height of the base, they are guided by the height of the ceilings of the basement.

The features of the construction of the foundation of the house remain important. If the foundation level coincides with the ground level, then the height of the base cannot be less than 70 centimeters, and sometimes it reaches one meter. Standard height, during construction country house reaches 50 or 70 centimeters. It is this value that is considered optimal for most areas with varied climatic conditions and different depths occurrence of groundwater.

So, to determine the height of the base when building a country house, you need to take into account:

• depth of groundwater;
• amount of precipitation;
• presence of a basement;
• the need to organize a technical room in the basement;
• view of the furnished foundation of the house.

Features of waterproofing and insulation at different heights

The effectiveness of the strip base will be reduced to zero if there are no ventilation ducts in it. These are holes, the distance between which should not exceed 3 meters. They are installed around the entire perimeter, ensuring high-quality air circulation. Internal walls and partitions are no exception. These holes can only be closed ventilation grilles. In the video you will see how to properly insulate and waterproof the basement of a house.

The use of any plugs is strictly prohibited, since the humidity present in the basement space leads to the formation of mold and mildew. When building a brick plinth, to organize ventilation ducts, it is enough to leave gaps in the masonry; in other options, pipes are used that are fixed between the blocks. The jumpers can be sheet steel or ordinary reinforcement.

Reliable protection of the base from groundwater is provided by waterproofing material. It may be roofing material or another type roll waterproofing, such as:

• glass ruberoid;
• rubemast;
• euroruberoid.

Lay it in two layers directly on the foundation, applying bitumen mastic or heated bitumen to it. Between layers of waterproofing material a layer is applied adhesive composition providing a strong connection.

The construction of a foundation is not limited to laying its underground part. It is built above the ground surface to a height of 50-70 cm top part foundation - plinth.

The plinth is the upper part of the foundation protruding above the level of the vertical layout (Fig. 1.)

The plinth is not only a support for the walls, but also takes on the function of protecting against natural influences: in winter it is covered with snow, in spring it is undermined by melt water, in summer and autumn it rains. Therefore, the strength and resistance of the base to unfavorable natural conditions should be its mandatory characteristics. Structurally, the base is practically no different from the foundation, but its appearance must correspond to the overall architectural design of the house. To do this, the outer part of the base is plastered, lined with natural or artificial stone or tiles. In the simplest finishing option, the base is rubbed down cement mortar and paint. The upper part of the base must be strictly horizontal.
The height of the base may vary depending on the topography of the site. But in any case, the height of the base should not be less than 50 cm above the planning level. A house with a low base seems squat and loses in architectural terms.

Socles are made from solid brick frost resistance grade 50 Mrz using solid masonry or concrete foundation blocks .

Waterproofing the basement of a house

Two waterproofing layers are placed on the base, each of two layers of roofing material on bitumen mastic. The first waterproofing is installed at a height of 20 cm from the level of the blind area, the second - along the top of the base. The purpose of waterproofing is to cut off the migration of moisture into the walls due to capillary suction of water from the ground and moistening the walls from melting snow and rain splashes (Fig. 1.). Previously, one waterproofing was installed at the level of the top of the plinth. Such waterproofing cut off the leakage of water into the walls, but the base itself was in a moistened state. As a result, the moisture accumulating in the capillaries of the base material increased in volume during winter freezing and ruptured the capillaries.
The process, repeated year after year, destroyed the material of the houses' basements. Therefore, they began to use double waterproofing of the base. To protect the base from atmospheric moisture, they are lined with brick, natural stone slabs or ceramic tiles.

Construction of the basement. Pickup

The most successful constructive solution The plinth is rubble masonry with simultaneous brick lining.
The basement superstructure over the strip foundation is made the same width as the foundation itself. Base columnar foundation(it is called a fence or fence wall) it is never thick: if it is brick, then the masonry is made of brick or half a brick; if rubble, then no more than 30 cm wide. If the soil at the construction site is rocky, sandy or gravel, then the fences are laid from ground level; if the soil is clayey, then bury the holes 20-30 cm into the ground, and underneath them make a sand cushion another 20-30 cm thick. Level the upper plane of the base (as well as the upper plane of the foundation) using a building level.
And one more thing that you should not forget about when building a basement - natural ventilation confined space, limited by basement walls, floor and soil. For free circulation of air in this space, ventilation windows (vents) measuring approximately 15 x 15 cm should be left in the basement on each side of the house at a height of 15-20 cm from the ground. To protect the underground space from rodents, the vents must be covered with gratings, and in the winter they should be filled with wooden plugs.

Laying the plinth with bricks

When constructing foundations, the base is laid out of red solid clay brick of a grade not lower than 75 or face brick with unstitching. For brickwork you can use a solution of composition 1: 0.3: 4 (cement: lime or clay: sand, by volume) - for foundations in low-moisture and wet soils; composition 1: 0: 3 - for foundations located in water-saturated soils.
Brickwork is done in horizontal rows, laying the brick flat (on the bed). Each brick of the top row should lie between two or more bricks of the bottom row, covering their joints. The order of laying bricks relative to each other, ensuring that their joints overlap, is called ligation. The simplest is single-row, or chain ligation, when rows of bricks across the wall (bonded) alternate with rows along the wall (lay). In this case, the transverse seams in adjacent rows are shifted by a quarter of a brick, and the longitudinal seams by half a brick (Fig. 2).

Mortar joints between bricks should be within 10-15 mm. The thickness of horizontal joints of brickwork should be 12 mm, vertical joints - 10 mm.
When plastering walls and foundation plinths, the seams should not be filled with mortar to a depth of 10-15 mm for better adhesion of the mortar to the surface when plastering it.
In order for the masonry to be of high quality, wooden slats, marked in height every 77 mm (brick thickness 65 mm plus joint thickness 12 mm), are attached to pre-installed pillars of logs with a diameter of 10-12 cm at the corners of the foundation. The top of the first row is secured with a mooring cord. Using the cord, check the horizontal position of the row. As the rows are laid, the cord must be moved upward. (Fig. 3.)

If this technology for laying a plinth turns out to be difficult to implement, then instead of a mooring cord, you can use formwork panels, or edged boards. They are supported on order slats and intermediate bars driven into the ground. Lines are drawn on the board to define the top of the row of bricks to be laid.

The laying begins from the corner and gradually moves to the left of the laid part of the plinth row. The trowel for applying the solution should be in right hand. With your left hand, remove the brick from the stack and place it on the mortar. Part of the mortar is pushed with a trowel onto the side edge or end of the previously laid brick, then the brick is pressed with the left hand, and with light blows of the trowel handle, press it in so that the top edge coincides with the horizontal line drawn on the board, or is in line with the mooring cord. When laying external versts, the mooring cord is pulled for each row at the level of the top of the laid row with a distance of 3-4 mm from the vertical plane. Usually the mooring cord is tied to nails secured in the joints of the masonry. To check the horizontal and verticality of masonry, use building level 500-700 mm long.

To control the quality of the masonry, after fixing the orders, beacons are laid out on them in the form of a shelter penalty or intermediate orders are installed (every 3 - 4 m). Part of the mortar into which the brick is pressed sometimes protrudes beyond the plane of the foundation base. It must be immediately removed with a trowel, put back in the box (bucket) and mixed with the solution located there.
Base for logs, paving stones and frame walls usually made in one or 1 1/2 bricks (i.e., 250 and 380 mm wide).

In a private house it is a basement, which serves as the first floor. Others consider it a standard ground floor, which is located below ground level. In any case, its creation remains unchanged and requires compliance with certain rules.

Flaws

It is worth noting that the construction is characterized by higher costs compared to conventional ones, and in some cases more economical option there will be an expansion of the construction area.

The approximate cost becomes clear after carrying out geological and engineering surveys, establishing soil type, level groundwater. Sometimes it turns out later that the construction of such a building in this place is impossible.

Basement floors in private houses require the creation of drainage, high-quality waterproofing and insulation, so it will not be possible to get by with simply forming an extension of the foundation. Failure to comply with waterproofing rules or the use of low-quality materials increases the likelihood of flooding.

To carry out such work, builders must be highly qualified, since the negligent attitude towards work in this case is different more likely undesirable consequences.

Lighting and ventilation

Since the installation of full-fledged windows in the basement is most often impossible, the premises will have insufficient space. Therefore, the location of living rooms is preferably on the ground floor. The most popular arrangement options are entertainment and sports premises: home cinemas, billiard rooms, swimming pools, saunas, gyms.

It is worth remembering that operation also involves large investments to maintain the space in the required condition. Forced ventilation the ground floor of a private house is especially relevant in gym and rooms with high humidity levels, and the creation will be required for saunas and showers. The pool located below ground level is also difficult to arrange.

When you can't do without a plinth

It is most often necessary when there is insufficient floor space above ground and it is impossible to accommodate all the planned premises.

In some cases, the size of the construction site contributes to the creation of a plinth. It may be small or have narrow shape, while the owner has the funds to erect a large building, and the space on the upper floors is no longer enough.

The arrangement is also common when there is a site characterized by the presence of a slope with a noticeable difference in height. In this case, the relief becomes the accent of everything landscape design and allows you to build a very original building.

The ground floor in a private house, the photo of which is presented above, gives respectability to the entire building and can accommodate various rooms, basement or utility areas. It is also worth noting that such a building has higher thermal insulation properties. With proper arrangement, you can reduce costs and speed up their payback. Thanks to it, you don’t have to worry about the loads that fall on the foundation, and the house itself becomes more reliable. in accordance with established rules, must be within 2.5 meters.

Varieties

There are three main types:

• recessed ground floor in a private house;
• speaker;
• located flush with the base.

The first option has become most widespread. This is facilitated by less exposure to moisture compared to other types. Also in this case, humidity does not have such a detrimental effect on other parts of the building, since the water quickly drains from the base.

The protruding type is optimal for houses with thin wall structures. This way you can arrange rooms that will be located almost underground. Sometimes it acts as a place to store seasonal and rarely used items.

Arranging the basement floor of a private house on the same level as the foundation is not always rational, since it will have insufficient protection from moisture and at the same time act as the beginning of the wall. Requires the use of additional waterproofing materials, which entails unnecessary costs. It is also worth noting the impossibility of improvement appearance building.

Materials

Due to the fact that the base is a continuation of the foundation, it is built from a material similar to that used to create the base. Sometimes it is possible to choose the materials from which the wall structures are made. Most often used ready-made blocks, brick and monolithic concrete. Regardless of the choice made, proper calculation is required. Particular attention should be paid to determining the thickness of the walls.

Screed and concrete plates act as a floor. The base can be formed from ready-made reinforced concrete slabs. Often used for cladding work wood material. If the basement floor in a private house rises significantly above the ground, it is possible to create full-fledged windows and doors in its upper part, and it is desirable that they face the south, west or east. Arranging openings on the north side is undesirable, as this can lead to deformation of the frames due to accumulation large quantity snow.

Ladder

It is advisable to start with the stairs to the ground floor in a private house, since it is an integral and important element premises. Three types have become most widespread staircase structures, providing a comfortable descent. Arrangement of the classic marching version is possible if there is sufficient space. If the design of the floor and its dimensions do not allow creating such a comfortable descent, a bolt or screw type is suitable.

Waterproofing

Separately, it should be noted waterproofing works. The underground structure must be coated on both sides with materials that protect against moisture. This will increase their reliability. Waterproofing elements located above the ground does not require mandatory internal waterproofing.

The ground floor in a private house, which is based on a solid concrete slab, has undoubted advantages:

• it is possible to arrange premises for any purpose;
• the structure is characterized by sufficient protection from negative external influences, for example, humidity;
• requires relatively little time for construction;
• outstanding structural strength.

High-quality waterproofing is the main point during construction. If this rule is not followed, the floor slab will have poor adhesion to the wall elements of the base. As stated earlier, the height of the base should be within 2.5 meters. For its construction, a pit with the required depth is dug.

Design work

First of all, when arranging it is necessary to install required thickness walls Here you need to build on the type of soil on the site and the location of the building. If the soil is sufficiently reliable, it is possible to create walls with a thickness similar to those of walls in other parts of the house. Otherwise, it is recommended to increase the thickness by 20-30 cm. When using wood to construct a building, the basement floor in a private house can be made from concrete blocks with your own hands.

An important step is drawing up a project, which must take into account the location of groundwater. This is due to the fact that the depth of the pit should not reach the water level. A preliminary ground survey is carried out to establish the possible depth.

• Why does a house need a basement?
• Basement of a house with double-layer walls.
• Features of basement waterproofing.
• Elimination of cold bridges in the basement.

The basement is the above-ground part of the foundation. This is a rather complex knot, where the vertical (basement, walls) and horizontal (floors and ceilings) structures of the house converge and adjoin each other.

Correct design, waterproofing and insulation of the base - the necessary conditions for the construction of a durable, economical and heat-saving house.

The figure below clearly shows what will happen if the house has very low base.

Plinth with a height of at least 20 cm. protects walls from moisture (in the picture on the left) A low base and absence of a base leads to moisture in the wall of the house (in the picture in the center and on the right)

The height of the base of a private house must be at least 20 cm. With a low base, there is a high risk of moisture in the wall of the house. The walls will be moistened by splashes when raindrops hit the ground, when snowdrifts melt, or from capillary suction of moisture directly from the ground.

Damp walls lose their heat-saving properties. Water freezing in the walls gradually destroys them. Dirt, dampness, fungus and mold appear on the walls outside and inside the house.

In areas with high snow cover, it is better to make the height of the base no lower than the level of stable snow cover. This rule is especially important to follow for houses with wooden walls.

To protect the walls of the house from moisture coming from the ground, two lines of defense are created:

• They increase the height of the base in order to remove the walls of the house as far as possible from the ground, the source of moisture.
• They waterproof the walls of the house and the basement in a dangerous zone of moisture exposure.

A high base increases the cost of building a house. Therefore, depending on the design of the walls and, they try to find a reasonable compromise between the size of the plinth and the level of waterproofing.

Be sure to arrange it between the base and the wall of the house.horizontal layer of roll waterproofing.

In some cases, which are discussed below, it is necessary to do additional waterproofing of the walls of the house.

For a private home it is recommended to make a recessed base. In a sinking plinth, the outer surface of the wall protrudes beyond the border of the plinth by about 50 mm. The water falling on the surface of the wall flows down and falls from the wall past the base onto the blind area. This solution prevents water flowing down the wall from reaching the horizontal waterproofing and flowing along it into the wall. For better water drainage A drip line is secured along the lower edge of the wall.

It should be noted that in addition to the moisture-proof function, the base plays a certain role in the architectural appearance of the house. A house on a high base looks more solid and impressive, and finishing the base can highlight the beauty of the floors of the house.

Correct basement of a house with single-layer external walls

The outer surface of single-layer walls is less protected from moisture than multilayer walls. Therefore, it is recommended that the base of a house with a height of at least 50 cm.

If the base of a single-layer wall is below 50 cm., That arrange additional waterproofing in two places:

1. In the wall, above the first or second layer of masonry made of aerated concrete or porous ceramic blocks, another layer of roll waterproofing is laid.
2. The outer surface of the wall, in the area of ​​the lower rows of masonry, is protected from water by a layer of vertical waterproofing. To do this, it is enough to use hydrophobic primers and waterproof plasters when finishing the wall. It is better, but more expensive, to line the base and lower part of the walls with a material with low water absorption, for example, clinker tiles.

Plinth design for a single-layer wall houses with basement or at home on foundation - slab Can

Dimensions of the basement of a house with two-layer external walls

Besides, thermal insulation of the base eliminates the cold bridge through the base and load-bearing part of the wall, bypassing the thermal insulation of the floor and wall.

If on site or weakly heaving, then the task of combating the forces of frost heaving is not worth it. In this case, it is only necessary to get rid of the cold bridge through the base and load-bearing part of the wall.

To eliminate the cold bridge in a house with single-layer walls without insulation of the base, it is necessary to raise the floor to the level of the second or third row of masonry blocks of the outer wall. This is sufficient, since the material of a single-layer wall has low thermal conductivity.

The load-bearing part of two- or three-layer walls is usually made of material with high thermal conductivity. To eliminate the cold bridge in two- or three-layer walls, you can cover only the upper part of the base with insulation, by approximately 0.5 m. below floor level. This will increase the path length heat flow on the base.

If the basement space under the house is not heated, then the basement is covered with thermal insulation on both sides.

For multilayer walls, another way to combat the cold bridge is used. The lower rows of masonry of the load-bearing part of the wall are made of wall material with low thermal conductivity. The floor level is raised in the same way as for a single-layer wall.

For insulating the base and underground part of the foundation, extruded polystyrene foam slabs (penoplex, etc.) are best suited.

Convenient to insulate strip foundations. Design of pile foundations with bored (including TISE) or screw piles more suitable for a cold base. Insulation of such foundations is quite problematic and expensive.

The basement space of houses with pile foundations is usually not insulated. design basement floor and the floor of the first floor of the house on pile foundation are chosen taking this circumstance into account.

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Base - rising above ground level outer wall, which is a kind of transition between the foundations and the facade of housing construction. This upper part of the building can serve as walls for basements, semi-basements and basements.

The design and construction of the basement part of the building requires a thorough approach. Special attention deserves such a parameter as height. A base that is too low will not be able to protect living spaces from moisture penetration. This negatively affects the integrity and service life of the building and makes living impossible.

The height of the base depends on the following parameters:

• type of base;
• house construction project;
• characteristic features of the soil;
• the intended purpose of the basement, if provided.

Construction regulations are also important and should not be ignored.

The costs of building the foundation and plinth make up the majority of the estimate. And if the project does not provide for a basement, some believe that the base can be made flush with the ground. This, of course, allows you to save money at the construction stage, but inevitably harms the building itself. The basement is an essential part of houses in the construction of which moisture-sensitive materials are used.

The main function of the basement part of the building is to protect the facade from contact with the ground. A barrier to soil water, rising through capillaries from the base, becomes waterproofing, which is laid directly between the walls of the facade and the base.

Along with isolating the building from the effects of groundwater, the plinth is assigned the following functions:

• protection of the facade from pollution;
• protection of the casing from mechanical damage;
• compensation for shrinkage under the weight of the structure;
• insulation of basement floors from negative influences;
• ensuring complete ventilation and increasing thermal insulation qualities;

In addition, the basement part gives the house aesthetic appeal and a complete look.

In order for the basement part of the building to perform all the functions assigned to it, it must have sufficient height. Otherwise, moisture will penetrate into residential premises, and the façade of the building will remain unprotected from pollution and mechanical stress.

According to building codes and regulations (SNiP), this parameter should not be less than 20 cm. This is the minimum indicator. It is better not to save money and build a base with a height of 30 to 40 cm. Structures built from wood are more susceptible to moisture, so the distance above ground level for the lower part should be at least half a meter and reach up to 90 cm.

The parameter from 20 to 90 cm is the recommended plinth height for buildings in the design of which there is no basement. If a house is being built with a basement, it can reach 2 meters. Calculate a more accurate indicator required height allows taking into account climatic conditions and average precipitation levels.

Doing this on your own is quite difficult, but possible. For this purpose, the average depth of snow cover over several years is calculated, and 10 cm is added to the resulting value. This data can be obtained by analyzing weather forecasts.

Main types of base

The construction of a high base leads to an increase in cost estimates. This is not a reason to save money. The main thing that outer wall, rising above ground level, was durable and had high performance properties.

The height indicator depends not only on the soil, foundation, project, but also on the position of the plinth relative to the facade wall. It can be made in one of the following options:

• Those who are sinking. The outer wall is located inside the façade. This option is suitable for buildings with fairly thick walls.
• To the speakers. The base plane is moved forward. This solution is the only one possible option for buildings with thin walls and ground floor.
• Flush. The basement part of the building smoothly transitions into the facade, that is, both the upper and lower parts are located in the same plane.

Each type has its own characteristics, affecting what the base will be like.

How does the type of base affect the height?

A protruding base is the most expensive option, but is necessary in cases where the project provides for a usable basement. The height in this case should be maximum. Otherwise, it is impossible to achieve good thermal insulation characteristics. There can be no savings in this case.

For buildings that do not have a basement or ground floor, it is most advisable to choose a sinking option. The facade overhanging wall becomes an ideal protection for the foundation of the house from mechanical damage and adverse atmospheric precipitation. The height of such a base is kept to a minimum. The higher it is, the lower the degree of protection.

Base height and foundation type

The basement part of the building on a low foundation (slab, strip, pile-strip) is made of bricks or blocks. The first option is less reliable. Blocks allow you to achieve more high level security.

Both plinth options require high-quality finishing to ensure protective functions. If groundwater lie close, arrange drainage, and if low - a blind area. The height of the plinth is made no less than the minimum recommended if there is no basement. Minimum indicator They take it solely to save money.

The pile foundation can be low, if the grillage is located directly at ground level, or raised. The most unstable is the columnar one, which requires mandatory compensation for soil heaving. For this purpose, the height is made at least 20 cm.

The gaps formed between pillars or piles are filled with bricks and covered with shields or asbestos-cement slabs. Due to the design features of the foundation itself, the base cannot be too high.

The height of the base when constructing buildings with a ground floor or basement

Buildings with exploited basements are most widely used in private housing construction. The rationality of this solution is due to the possibility of using this part of the building both for economic needs, placing a laundry room, pantry, boiler room, cellar in the basement, and for expanding the living space, arranging a study, bedroom, gym, and so on.

Sometimes both of these purposes are combined. It all depends on the expected building area. The main thing is that this approach is more economical than adding an additional floor above ground level. The total height of the basement here is much greater than in buildings without a basement. According to SNiP, it is equal to at least 250 cm.

The amount by which the base will rise above ground level depends on the purpose of the basement. If it is intended to be used as a utility room, it is permissible to take the minimum limit. On the ground floor under living rooms You cannot save, so a small margin must be added to the recommended height.