Increasingly, the roof has not only functional purpose. Often this element is the highlight of the building. Such roofs have many planes that are connected under different angles. Some connections - with positive angles - are designed in the form of a ridge, some - with negative angles - in the form of valleys. To ensure that the attic is always dry, the roof valley must be done correctly.
Valley roofs
On roofs of complex shapes, when installing protruding dormer windows, sharp corners. They are obtained at the junction of two slopes. The junction is called the valley, and the roofs are called valleys.
Roofs of complex shapes look very decorative and are a decoration of the building, but their design and installation is not an easy task - connecting planes is not easy. Because of design features These areas of the roof bear a heavy load: there is always a lot of snow and water. Therefore, the sheathing is made reinforced, and waterproofing measures are much more serious than on the rest of the surface.
Features of rafter systems
Rafters from different stingrays in the valley they can be connected at different angles (depending on the shape of the roof). At the junction, a rafter leg is installed, to which the rafters from the slopes are attached. For a short length (up to 2 m), it is enough to fasten them on nails (2 on each side); for a significant length, the joints are reinforced with metal plates.
Rafter connection
In places of greatest load (in the widest place), the valley rafter leg is supported from below by a jib.
Lathing
At the junction of two roof slopes, reinforced sheathing is required, and its design depends on the type of roofing material:
We have provided typical requirements and sizes, but some manufacturers may have specific requirements. When purchasing roofing material, you will be given instructions that will describe the entire installation process and requirements for the sheathing, etc. technical points. It is clear that you must adhere to their recommendations.
Valley device
There is no particular point in talking about the device in general, since each roofing material has its own characteristics. Therefore, we will consider the most popular ones separately.
On a metal roof
As already mentioned, lathing is done twice as often under metal tiles at the junction of the slopes. The bottom plank of the valley is laid on this sheathing - this is a galvanized sheet with a fold line in the center and sides along the edges. This element belongs to the accessories and is painted to match the base material. It comes in two-meter pieces.
Metal roof valley
Installation of the valley strip begins from the bottom. The edge of the element extends slightly beyond the roof overhang, is cut 20-30 mm below the overhang, and a flange (side) is formed from this “remainder”. Please note that the valley strip should end behind the overhang; if there is a drain gutter, then above it. If it is made shorter than the overhang, then water will flow into the roof.
The next sheet is laid on top, with an overlap of 20-30 cm, the joint is coated with sealant (you can coat the entire overlap with bitumen mastic). Lay as many sheets as necessary, cut them off near the ridge and secure them.
There are two ways to attach the valley sheet
When constructing a valley, the main task is to ensure tightness. From this point of view, the second fastening option is more correct - it leaves no holes, even if they are covered with a rubber gasket.
One more thing. The bottom bar should have sides on both sides, preferably more than 2 cm in height. They are needed so that water flowing from the slope cannot get under the metal tiles.
A sealing tape is glued to the fixed strip, at a distance of about 20 cm from the bend. It comes with self-adhesive tape. Before installation, the protective coating is removed and the tape is glued. Next, metal tiles are laid, which are cut so that the center of the valley is 60-100 mm. Manufacturers do not recommend placing the cuts closer to the center.
The sheets are attached to the sheathing in the regular places - in the lower part of the oxen 20-30 mm below the step. The distance from the fastener to the bend is at least 250 mm.
After fixing the metal tiles, the roof valley is ready and can remain in this form. But appearance Not everyone is happy with cut sheets. In order to close them there is a decorative overlay, which is called the upper valley. She performs decorative function— covers the cuts; it is simply not used quite often.
Features of the valley outlet above dormer window watch in the next video.
Made from corrugated sheets and slate
Under these materials, several boards are laid lengthwise in the valley. A strip of waterproofing is attached to them, which is then connected to waterproofing membrane, fixed on the slopes. The overlap should be at least 10-15 cm, the joints are connected using double-sided tape.
In this case, the sealing tape can be supplemented with sealant. A strip of sealant is applied on both sides of the inflection point of the roof. After installing the roofing material, a large free space remains in the projections of the wave. Water, snow, and debris can get there. To prevent this from happening, fill the gap with sealant, applying it in layers.
In the case of a profiled sheet, there are several options for designing the valley:
Open or closed type You choose the connections of the slopes, the structure of the entire pie remains the same. Only the method of cutting the corrugated sheets changes.
Roof tiles
The structure of a valley roof made of tiles is exactly the same as in the case of a profiled sheet. The difference is that the continuous sheathing must be larger - at least 35 cm wide on both sides of the joint. The fastening of the tiles in the valley has its own peculiarities - some fragments are cut so much that it is impossible to fasten them with a standard lock. Then a hole is drilled in the top of the tile and a soft, acid-resistant wire is threaded through it. Drive a nail into the sheathing, twist a wire onto it and fix the tiles in the required position.
The second option for constructing a valley with tiles.
Ondulin
In the case of ondulin, the sheathing under the valley is not solid, but two boards located at a distance of 15 cm from one another, symmetrically relative to the center of the valley. A special gutter is placed between them.
Installation starts from the bottom and moves up. The first sheet of the valley gutter is laid flush with the edge of the roofing material, and the shape is corrected. They are nailed to the sheathing from the top side. The next sheet is laid with an overlap of at least 15 cm.
After the entire gutter is laid, installation begins roofing sheets. First, they trim with a margin - the mark is placed 5-6 cm further than necessary. Cut along the intended line (with a jigsaw or grinder). Place it in place, mark the exact cutting line - along the protrusion on the gutter. Cut it off a second time and put it back in place. Since the ondulin sheet weighs little, all operations are easy to perform.
The laid sheet is secured with special roofing nails with a head painted to match the coating. It is necessary to fasten it into each wave, retreating as far as possible from the midline of the valley.
Installation of a valley on a roof made of Ondulin is available in video format.
Tin roofs
In private housing construction, this type of roofing material is rare, however, there are such roofs. The tin roof valley is connected manually, using a mallet and a special tool.
A properly equipped roof of a house is an important component providing protection to the building from winds, precipitation or sunlight.
The main load falls on the roof, as on the outer plane, which has direct contact with all weather or climatic manifestations.
Any defects in the design of the roof mean the possibility of water getting inside, the formation of centers of destruction of the rafter system or the danger of demolition of the roof due to gusts of wind.
That's why correct use roofing, which form a sealed layer that reliably separates inner space from contact with the atmosphere, is an important and responsible part of the roof design.
Roof coverings are divided into two groups:
- The actual coating, i.e. leafy or roll materials, in the set creating the plane of the slopes.
- Extensions - all design elements of junctions, transitions, drains, etc.
At the same time, it is the additional elements that require the most careful, responsible approach to installation, since they often take on most loads for drainage or removal of rain or melt water and snow. One of these elements is the valley.
A roof valley (sometimes a valley) is a term that has two meanings. First of all, This is the area of the roof where two planes meet, forming a depression. This - general concept, defining the meaning of the term, its meaning. In construction practice, another, narrower meaning of the term is used: this is what they call type of additional elements made to design the joint of planes. The presence of two interpretations sometimes causes some confusion caused by confusion of the two concepts due to lack of awareness.
Endovy (in in a general sense) are of three types:
- Open.The place where the planes meet does not have a tight seam and is covered on top with an additional strip.
- Closed. The joint is tight and straight.
- Intertwined. A tight joint with transitions of elements of the roofing material pattern onto each other in an alternating order.
The difference between these methods is not functionality, but purely external.
The second and third types are much less common, since their construction requires workers with experience and special knowledge. At large selection roofing materials available for sale and different properties and installation specifics, find people who know how to design complex roofing elements, not easy. In addition, all work is carried out in difficult conditions, at altitude, which creates additional difficulties.
It should be taken into account that in any case it is not possible to achieve complete tightness of the connection, and the meaning of all efforts, in fact, comes down to achieving a purely decorative effect, which often means unnecessary waste time and labor.
Valley device
Valleys as an additional element are also divided according to the method of installation:
- Bottom end. The internal valley is installed before laying the roof, since it is located under the general layer. In any case, with any type of valley design, the bottom strip is present as a mandatory element, since it is it that serves as a gutter that drains water into the drain. Without it, the junction of the planes will be a continuous gap.
- Endova upper. This element is installed on top of the roofing material and serves, firstly, to create visual completeness, neatness of the connection, and secondly, it prevents the accumulation of various debris in the recess of the roof. Any foreign objects, pine needles or fallen leaves, small debris, etc. will gradually create a barrier to the free flow of water, so it will find a way out in another place, which will certainly create a problem. The presence of a top bar prevents such accumulations.
Both types of valley strips have their own installation features. Each type of roofing material has its own set of additional elements, fully consistent with each other both in constructive and design terms, so before installation you should familiarize yourself with the rules and features of working with this material.
What is a roof valley: photo
What are valleys made of and what roofing materials are they used for?
For the manufacture of valleys, the same material is used as for the main one. 
coatings - asbestos cement is used, for or - galvanized steel sheet, etc.
If a protective coating is used to protect a material from corrosion, as is done in the production of metal sheet materials, then valleys are similarly provided with a layer of protection.
That is, complete compliance of elements is achieved, which when assembled look like parts of a single whole. However, in some cases they resort to using additions of one type to decorate the material of another.
NOTE!
The installation of the lower strip is carried out under the roof and excludes the possibility of seeing it, so matching materials in this case is not required.
Most often, this combination occurs during the construction slate roofs, since asbestos-cement elements are not as common as other components. Exiting the situation in this way, of course, somewhat affects the aesthetic perception of the roof, but functionally everything works correctly.
Anyway, Fully matching components are created for all sheet roofing materials, allowing you to design all areas of the roof, and valleys in this sense are no exception. It makes no sense to use them for working with soft roll coverings, since their installation technology involves completely different actions, and sealing corners does not require additional structures.
Diagram of the rafter system at the site where the valley is installed
Rafter system in places of transition of one plane to another should provide straight lines and straight lines without depressions or distortions that could cause the valley to be installed incorrectly.
The device for connecting two valleys on a slope can be of the following types:
- Butt-butt. With this method, rafters of different slopes are connected with their ends at an angle. Careful calculation and accuracy in work are required to avoid bending or distortion.
- overlap. The rafters do not connect to each other, being placed “at random”. This option provides a greater guarantee of maintaining the clarity of the transition of planes and maintaining straight lines.
Rafter system for the valley
For correct and precision installation rafters First of all, you need to designate the runs - the lines connecting the planes. This is done using a stretched rope between two extreme points run and are guided during assembly along this line. With due care and attention, the design turns out smooth and suitable for performing its functions.
CAREFULLY!
The design of the rafters at the transition points of planes requires increased strength. Reinforcement with additional posts and spacers is required.
An important element of the valley rafter system is. At the junctions it is made continuous, with mandatory. Installation of the bottom strip should be done on a flat, straight area so that the pressed strip does not receive any deformation.
Any bending will cause peeling protective coating , which will automatically start corrosion processes and cause quick exit the planks are out of order. If we take into account the presence of a layer of insulation and waterproofing, lining the inner surface of the attic space, and other finishing coatings, detection of damage to the plank will not occur immediately.
By then, significant damage will have been caused due to water penetration into the roofing materials. Replacing the strip will also require serious work, as well large quantity time.
Alternative option
Installation of the valley
How to install the additional element correctly:
- First of all it is necessary make sure that the substrate is constructed correctly and accurately, that there are no distortions, and that the structure is strong. Loads on valleys can be significantly higher than on flat areas of slopes, since it is in the gutters that snow accumulates, creating strong pressure on the system.
- Wooden elements rafters and battens are treated with an antiseptic and the area is waterproofed. It is an additional operation for the valley, general waterproofing roofing materials - another position.
- The bottom strip is being installed. The procedure is carried out from the bottom up, the individual parts are overlapped with an overlap of 10-20 cm. All joints are treated with sealant.
- The roof is being laid. The joints between the material and the bottom strip are additionally sealed.
- The top bar is installed.
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Additional elements
Constructive and functional features valleys - ensuring effective drainage and an aesthetically pleasing appearance of the valley roof.
The elements available on the market allow us to fully solve both issues, provided that they are installed correctly and carefully. It is quite possible to carry out the work yourself, the main thing is to familiarize yourself with the procedure and the specifics of the material and do not forget about safety measures when working at height.
Useful video
Visual video tutorial for installing a valley:
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In contact with The roof is one of the main functional elements of any structure. Moreover, this is a rather complex structural element, and the more complex it is, the more careful approach it requires. Complex configuration
, on the one hand, makes the roof more visually beautiful and interesting, and on the other hand, makes it more vulnerable due to the formation of bends.The roof is one of the main functional elements of any structure. Moreover, this is a rather complex structural element, and the more complex it is, the more careful approach it requires. A complex configuration, on the one hand, makes the roof more visually beautiful and interesting, and on the other hand, makes it more vulnerable due to the formation of bends. Endows are practically invisible, but they can both spoil the appearance of the facade and emphasize its advantages. The roof truss system with a valley, therefore, not only allows functional tasks
The endow is the place where the roof slopes meet, forming an internal corner. It is an obligatory element of buildings that have a T-, L- or cruciform shape, or have pronounced slopes. To this list we must also add bends formed on or protruding.
It ensures uniform drainage of precipitation collected at the corner, a kind of analogue of a gutter, that is, they are under significant influence of moisture. That's why the rafter system complex roof requires special attention.
The internal corner of the structure is formed by two strips, and each of them performs an important function:
- lower (PEN) is a special plate that is bent in accordance with the angle of the roof slopes. It is attached to the underside of the cornice board with self-tapping screws. PEN encloses and protects against the flow of precipitation into the junction of the slopes. Installation of the bottom valley is carried out before laying the roof covering;
- upper (PEV)– carries an artistic and aesthetic meaning and is installed after laying the covering.
On a note
As a rule, the same material is used for manufacturing as for the roof. It is often replaced by metal sheets, preferably made of galvanized steel, as it prolongs service life roofs. And so that the finished roof does not lose its attractiveness, you need to choose the right shade of the material.
Types of valley
Any, even small, error in calculation or error in the installation of a rafter system with valleys is fraught with irreparable consequences, including the collapse of the structure. In winter, for a long time they are under the influence of colossal loads.
Depending on the installation method, there are different:
- Closed and articulated structures- typical for roofs with steep slopes or for certain roofing coverings where the roofing elements are intertwined, like, say,. These structures require an additional layer of waterproofing.
- Open. In this case, the slopes are adjacent to each other. This is also taken into account when the rafter system is installed. The gap between the slopes is closed with a special gutter, through which precipitation is effectively drained. In this case, additional waterproofing is not required.
Installation for soft roofing
Let us dwell on the basic principles of the structure in the case of a soft roof.
Preparatory work
You can create a negative break in at least two ways:
- open;
- undercut method.
The base is prepared depending on the chosen option.
- Open. Along the length of the valley, a valley carpet (KE) is laid on the lining barrier, displaced horizontally by 20–30 mm. From the inside out, along the entire perimeter, it is coated with, say, TechnoNikol bitumen strip with a width of 100 mm. The layer thickness is selected in accordance with the consumption rate. By front side the carpet is fixed using roofing nails in increments of 200–250 mm with a distance of 20–30 mm from the edges.
If it is not possible to lay it as a continuous sheet, which is very desirable, then the installation is carried out with a longitudinal overlap of 300 mm, carefully gluing.
- When using the “undercut” option, KE is not needed.
Open installation
- ordinary tiles are laid on the KE up to the central axis;
- all tiles that cover the inner corner between the slopes are additionally secured to the upper apex using nails.
- the distance from the axis to the fastening element must be more than 0.3 m;
- then, using a coated cord, beat out two lines; ordinary tiles will be cut along them;
- the waterproofing carpet can be damaged when trimmed, so a plank is placed under each tile during work;
- before final fastening apply to areas without a self-adhesive layer bitumen mastic;
- if the difference between the slopes of the slopes is large and, accordingly, the water flow also differs noticeably, the gutter is shifted in the direction of the lower water flow. Otherwise, water will wash away the joint between the valley carpet and the ordinary tiles;
- The width of the gutter ranges from 50–150 mm. The choice depends on the characteristics of the location of the object. If it is built in a forest thicket, it is recommended to increase the width of the gutter so that foliage can be easily washed away.
Installation using the “undercut” method
- The laying of ordinary tiles begins with a slope that has a smaller angle of inclination. In this case, it is expected to enter the second slope, which is steeper. It should not be less than 300 mm.
- similar to the previous case, additional fixation of each panel in the upper corner is necessary.
- after the first slope, which has a smaller angle of inclination, is covered, a chalk line is “beaten off” on the other at a distance of 70–80 mm from the axis. This is the place where the tiles will be cut.
- This applies to each tile, and before they are finally fixed, mastic is applied to the places where there is no self-adhesive layer on the back side.
On a note
The intertwined method involves performing the same steps as during “undercutting” with the only difference being that the ordinary tiles are intertwined when laid on the adjacent slope.
Device
The valley rafter system most often consists of slanted rafters. Moreover, since it is assumed that they have the same height, the sloped rafters in the valley design bottom will rest against the mauerlat, and the opposite one will rest against the ridge girder.
To form different types of roofs: and half-hip, it is necessary to provide a different geometric shape and height of the ridge, not only of the main structure, but also of the secondary one.
Rafter system with L-shaped roof valleys
- The racks of the main roof truss structure and the secondary roof purlins are interconnected. At the same time, breakers serve as support for the latter.
- The roof purlins of the secondary roofs are connected.
- Whatever the height of the purlin at the main roof, the connection is made through nailing.
- On the slanted rafters, in a staggered position, splices are installed, which are connected to each other in the ridge unit. Similar to a hip roof, they rest on bars, which are previously sewn onto the rafters.
Diagonal rafter legs Depending on the device, both spacer and non-spacer types can work. As already noted, the splices rest against the diagonal rafter. At the same time, they transfer significant compressive stress to it. The rafter, in turn, resting its lower end against
The roof valley is a roofing element in the form internal corner. It is located at the junction of the roof slopes. If the building does not have a strict rectangular shape and build a standard gable roof problematic, they build gable roofs on the main building and on the extensions; the line where they join each other forms valley roofs.
At the same time, some novice roofers do not pay special attention to them during construction, making mistakes. In some cases, these errors can lead to the destruction of the roofing covering in the valleys, and if gross errors are made, the entire roof may collapse.
Valley roofs must withstand heavy loads, since they can accumulate (with incorrect design rafter system and errors during installation of roofing) precipitation. In addition, the construction of the valley must be carried out with the expectation of increased wind load. Therefore, it is important to properly design and build the rafter system. How to do this will be discussed below.
Description and design
Definition: valleys are the joint elements of the converging slopes of a multi-pitched roof. This structural element is considered a key element that should be built especially firmly. This is due to the fact that snow and ice can accumulate on the roof in these places, forming “plugs” that can lead to damage to the roof covering (especially soft roofing) and the collapse of the entire roof structure. In addition, water can accumulate in such places, which in cold weather will turn into ice and lead to damage to the roofing.
The valley forms the space between two adjacent roof slopes, forming a tray (receiving angle) for collecting water on the roof.
Therefore, at the design stage it is necessary to pay attention Special attention how the valley should be installed and what design should be preferred. To do this, a diagram is first drawn up, which must be agreed upon with the architectural bureau. In addition, during the installation of the rafter system, when joining the slopes of the structure, you must be especially careful. It is worth paying attention to the materials that will be used in the construction of the valley. Most often they are made from steel sheets (galvanized). Such material will significantly increase the service life of the valley.
Roof valleys can be of almost any design, since everything depends only on the design of the building. However, the structural design of the valley for all types of roofs is the same and consists of 2 strips: an upper valley and a lower valley. In this case, the lower bar is installed at the junction point, where a negative angle is formed. The presence of this bar is necessary to ensure strength characteristics structure, as well as to prevent moisture from entering attic space(or under the roof). It must be installed after the installation of the roofing is completed.
In general, it is worth noting that builders divide valleys into 3 types:
- open;
- closed;
- intertwined.
They differ from each other only in the type of connection of the roofing covering at the joints of the slopes, and in what roofing material was used to cover the roof. Features of closed and intertwined structures are as follows: when constructing closed and intertwined structures, it is necessary to ensure additional waterproofing. Open valleys do not require an additional protective layer due to the design features. The protective layers for the open valley are installed in the same way as on the roof.
The top bar of the valley is installed to ensure better drainage of precipitation, as decorative element. It protects the sharp outer corners at the junction of the slopes (like the ridge) and gives the entire structure a finished look. The installation of such a strip is carried out at the final stage, when the roof is almost ready.
An important point that the installation of a valley requires is the application of preliminary markings and precise placement of the plank. It is worth noting that the slightest mistakes made during the installation of the valley can lead to roof leaks and rotting of the rafters. Therefore, it is strongly recommended that you contact specialists to perform this work. If, nevertheless, the construction will be carried out on its own, then it is necessary to follow certain rules during design and construction. This will be discussed below.
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Design stage
Valve device on soft roof: 1 – valley axis; 2 – lining carpet; 3 – valley carpet.
A simple roof shape is the usual gable roof. How more complex design roofing, the more difficult it is to implement it. To erect a multi-pitched roof, it is better to contact a construction organization. When designing joints, you should take into account the number of joint points that need to be strengthened structurally - laying additional supports and beams. All reinforcement structures must take into account the actual dimensions of the roof with errors during its construction.
When designing, the house is conventionally divided into rectangular sections that are joined to each other. Basically, the breakdown occurs according to the principle of the main room - one large rectangle, the extensions - small ones. In this case, the drawing must be made to scale and must include the calculation and drawing of the entire roof area. The valley lines will be at the junction of the extensions and the main building. The most common valleys on the roofs of buildings are in the shape of the letter “T”, which allows you to build the same type of rafters and simplify the design. That's why inner work construction of the rafter system and installation of tiles is significantly simplified. After all, identical rafter shapes for converging blocks are much easier to design. The main difficulty in this case will only be connecting the roof and laying the planks.
At the same time, in order to avoid damage to this strip, you must carefully select the attachment points and should be secured with long self-tapping screws. It is recommended to use additional protective layers-linings, which increase the protection of the roof against leaks in the area of the installation joints.
Some people (even builders) don't know what a valley is. But if to an ordinary person This is excusable, but the builder is not. He must know everything construction terms, as well as carry out work competently. When considering the design of a valley roof, special attention should be paid to the fact that they are quite important element roofs. But what is it?