Increasingly, the roof has not only functional purpose. Often this element is the highlight of the building. Such roofs have many planes that connect at 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.
On roofs of complex shapes, when protruding dormer windows are installed, sharp corners are formed. 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.
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.
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, requirements for the sheathing, and other technical issues. It is clear that you must adhere to their recommendations.
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.
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. She goes on 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.
Attach the sheets to the sheathing in regular places- in the lower part the oxen are 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 not everyone is happy with the appearance of the cut sheets. In order to close them there is decorative overlay, which is called the upper valley. It performs a decorative function - it covers the cuts; quite often it is simply not used.
See the following video for details of the valley exit above the dormer window.
Under these materials, several boards are laid lengthwise in the valley. A strip of waterproofing is fixed to them, which is then connected to a waterproofing membrane fixed to the slopes. The overlap should be at least 10-15 cm, the joints are connected using double-sided tape.
IN in this case You can supplement the sealing tape 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 connection of the slopes, the structure of the entire pie remains the same. Only the method of cutting the corrugated board changes.
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.
In the case of ondulin, the sheathing for 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, the installation of roofing sheets begins. 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.
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.
So that the roof meets everyone's needs architectural features modern buildings, it is often made in the form of structures from many multi-pitched roofs. Geometrically complex frames of the rafter system have a large number of junctions of pitched surfaces that form the internal corner of the roof. Such areas in the design wooden roof are called valleys. Another name for this element is a valley or valley gutter. Having a v-shape, the roof valley actually plays the role of a gutter through which water flows are directed and removed. Proper installation of this element is of great importance, since installation errors can lead to leaks, damage to the insulation and additional repair costs.
The valley is one of the most important and complex elements of the roof structure. The interface between adjacent slopes is subject to severe climatic loads during operation. When it rains, water flows down it from neighboring slopes, and in winter snow accumulates here.
A properly installed valley not only protects the house from bad weather and precipitation, but also extends the life of the roof.
Typically, the valley consists of a decorative upper strip that covers the junction of two slopes, and a lower gutter, which is located under the roofing.
The number of valleys depends on the design features of the roof, as well as on the presence of additional roof windows.
Depending on the design features of the roof, the number of valleys installed will vary.
The design of the valley involves the construction of a base in the form of a continuous sheathing, on which a layer of waterproofing is laid, as well as the presence of a lower and upper element. The lower valley strip serves as a gutter, and the upper element serves as a decorative detail covering the joints of the slope. Most often, these roofing elements are made of metal. The highest quality material for making valleys is steel sheets coated with polymer coatings and special coatings. In some design options top part valley is not used.
To improve the waterproofing properties of the lower valley, its upper flanges can be sealed with self-expanding porous material
Depending on the angle formed at the junction of the roof joints, there are three types of valleys:
The design of the rafter system, which serves as the basis for installing the valley planks, depends on the intended type roofing. In this regard, there are several types of lathing for laying valley planks:
Installation of the valley is carried out in the following sequence:
The drip cap is made of the same material as the main roofing covering
The waterproofing material protects the counter-lattice strips from getting wet on the side and is attached to them with a construction stapler.
When gluing the membrane, it is necessary to make an overlap of at least 10 cm and glue it with double-sided tape
A gap is left between the bottom valley strip and the waterproofing film to drain condensate
Wooden sheathing laid on counter-lattice bars is necessary for ventilating the under-roof space and for attaching the finishing coating
The bottom battens of the sheathing in the valley area are trimmed to form an even joint
To counteract snow loads, a thick sheathing is installed under the lower valley strip
If there is no drainage system, installing an eaves apron is not necessary.
The installation process at the junction of two valleys is carried out as follows:
To prevent moisture from penetrating into the under-roof space, bends are made along the edges of the valley planks.
Foam strips must be installed to protect the space under the valley strip from water, snow and dust
Sheets of metal tiles are cut so that they extend onto the bottom bar of the valley by 13–15 cm
A smaller overlap will lead to the foam strip being destroyed due to exposure to solar radiation, and a larger overlap will complicate the installation of the tiles.
The cutting line is applied with a dye cord along the marks located at the top and bottom of the valley, and is marked on both sides of the groove.
The valley node looks like a concave angle between two roof slopes. To fasten this roof element, roofing screws are used, which are equipped with a rubber or plastic washer. The washer performs several functions:
The rubber washer provides soft pressure on the screw and waterproofing of the hole
When installing the valley strip, an overlap of at least 10 cm must be made.
To better seal these roofing elements, it is necessary to use sealing tape.
The lower valley strips are mounted directly to the wooden sheathing using clamps secured with nails or self-tapping screws. The upper element of the valley must be screwed with self-tapping screws to the metal tile. It should be noted that the screws for fastening the upper valley should not rest against the lower gutter. The gaps between the roofing and the gutter sheets must be filled with foam rubber sealant.
Clamps secure the bottom strip of the valley without damaging its edges
When installing valley units, you should pay attention Special attention on the quality of the sheathing. It is recommended to install the lower gutter on a continuous sheathing, the width of which should be no less than the width of the valley itself.
Installation of valley nodes is carried out as follows:
The brackets should be attached not to the regular sheathing, but to the thickened sheathing, otherwise they will interfere with the even laying of the tiles.
The upper groove is laid on the underlying one with an overlap of at least 10 centimeters. When laying, it is necessary to align the transverse ribs of the gutters and secure subsequent grooves in the same way as the first.
When installing a valley from several planks, it is necessary to make an overlap of 10 cm
An overhang aerial element is installed to provide additional support for the bottom row of metal tiles, as well as to prevent birds from entering under the roof.
If the discharge is larger, it will hold debris and fallen leaves in the gutter, and also prevent snow and rainwater from sliding.
The functionality of the valley is directly related to the quality of its foundation. To strengthen the valley, it is better to use continuous sheathing.
To strengthen the valley nodes, instead of standard waterproofing, non-woven polyester materials can be used
Installing polyester fabric with bitumen impregnation allows you to solve a number of problems:
If the valley is installed on a tile roof, trimming of the roofing material elements is often required:
Trimming the tiles must be done on a machine with a circular saw.
All laid elements must form a straight line parallel to the axis of the groove
Half tiles add the missing roofing fragment if in this row most of the surface of the last covering element falls under trimming on the valley
Corrugated tape is a convenient and effective material for sealing protruding parts of the roof
You cannot fasten tiles through the valley groove, as precipitation will flow under the roof where the self-tapping screw passes.
Installing a valley gutter requires care and skill. Since this roofing element carries a large amount of rainwater, the slightest mistake during its installation can lead to serious problems and additional costs. The most common mistakes when installing a valley are:
If the tiles are cut unevenly, the roof will have a sloppy appearance, and water and snow will flow off it intermittently
If the screws are not tightened correctly, water will flow into the under-roof space, contributing to the destruction of the rafter system.
The process of installing a valley requires special knowledge and construction skills. Therefore, it is better to entrust the installation of this roofing element to experienced specialists. In this case, errors that lead to serious problems will be eliminated.
0
Last revision: 10/19/2015
The complex roof structure makes the house more attractive and adds respectability to the appearance of the building. When installing a tent or hip roof appears structural element, called endova. It is located at the junction of two slopes and is a place for snow accumulation and water drainage. That is why the design of the valley requires tightness and high strength.
The valley is a functional part of the roof; it is a gutter formed at the junction of the slopes. Like any connection point, it experiences increased load, so the reliability of the entire roof depends on the strength and proper design of the roofing element.
There are two types of valley: the lower one, which protects the joint from precipitation, and the upper one, which, in addition to being protective, also performs a decorative function. The installation method determines the type of element:
Roofing schemes are developed at the design stage, and then the type of valley is selected, which depends on the angle of the slopes and the material used for the covering. The lower valley is installed on the rafters, so it must be marked in the roof plan. Depending on the selected roofing material, the structural element at the junction is made of metal or soft tiles.
Note! Cink Steel - practical choice, it ensures reliable operation of the valley for a long time.
The first step in constructing a valley is the installation of a continuous sheathing; it can be made from planks packed side by side or from edged boards, which are treated with an antiseptic to protect against moisture. The width of the sheathing should be about 20 cm in each direction. A solid surface will strengthen the strength of the unit, which bears a high snow load.
A layer of waterproofing is laid; this component should not be excluded, because the roof valley must ensure complete waterproofness. For a sealed base, it is better to use rolled bitumen-based material with basalt topping for strength. If the waterproofing consists of several parts, the sheets are laid overlapping.
The open type of valley is used more often than others; to install it, you need to make a special valley. The material for it is a strip of galvanized steel, bent at an angle greater than the valley.
The lower valley has a curved edge that prevents water from overflowing; it wraps its lower part towards the cornice. An overhang of 8 cm is left in this place for secure fastening. A sealant is placed at the junction with the ridge. Fastening is done with self-tapping screws to the sheathing, drilling step is 30 cm. Laying occurs from bottom to top if the groove consists of individual parts, then they are superimposed on one another with an overlap of up to 15 cm. The joints are protected with silicone sealant.
When they are cut off, leaving up to 10 cm to the center of the valley. Fastening occurs with self-tapping screws, which are tightened without approaching the center of the corner closer than 25 cm. The screws pass through the metal and the valley strip, fastening the structure.
The upper valley is made of roofing material; it is fixed after laying the main covering and covers the sections of the laid sheets. It is attached to the upper junction points of the metal tiles.
To install a valley on a roof with corrugated sheeting, you will need a continuous sheathing and waterproofing that is 10 cm wider than the valley strip. small corner between the slopes, the size of the lower valley should be maintained at 50 cm in both directions. The overlap of the parts on each other is at least 20 cm. The lower valley extends 25 cm under the ridge. After attaching the corrugated sheeting, a decorative strip is laid.
For a soft roof, the valley is equipped open method. The valley carpet is laid on bitumen mastic and nailed. The overlap of the canvases is up to 30 cm and must be glued. Ordinary shingles are attached 30 cm from the axis of the corner, their edges are fixed with bitumen.
The endow is a complex and important element of the roof; its installation should be approached armed with installation knowledge. Numerous photos and video tutorials will help you with your work.
This is how the bottom valley strip is installed:
Where to start installing the valley, what needs to be provided for - about this and much more below.
At first glance, installing a valley roof seems to be a rather complex and problematic process. Therefore, many consumers prefer to pay builders rather than do this work themselves. In the article we will further describe in more detail what a valley is, and also provide detailed instructions according to its construction.
On roofs with complex configurations that include several slopes at once, internal joints inevitably occur. Snowfall, rainwater, and all kinds of debris most often accumulate in such places. In addition, they are quite difficult to maintain.
The valley, or valley, is an element that is laid along the inner corner of the roof under the slopes. It is designed to protect the structure from water flowing under the roofing and ensures free evacuation of precipitation from the roof surface.
The number of valleys will depend on the following factors:
As a rule, the construction of a valley made of corrugated sheets involves the presence of two planks, which are bent at an angle coinciding with the angle formed by the adjacent slopes. In this case, the lower element serves as a drain, and the upper one is rather decorative.
In some cases, the top piece of the valley is not installed. This depends on the type of roof covering, as well as the features of the roof. Be that as it may, proper execution of the valley connection ensures the reliability and waterproofing of the roof structure.
There are some standards for arranging a valley:
There are several types of roof valleys made from corrugated sheets based on the configuration of the joints between the slopes:
Let's consider the features of each type of valley.
An open valley has the following advantages:
If we talk about the shortcomings, then such a valley does not look very beautiful.
Among the advantages of closed or interlaced grooves are:
But this design has significantly more disadvantages:
Depending on the intended roofing material and the design of the rafter system, the construction of the valley will be carried out differently. In this case, we mean the type of sheathing. Recommendations in this regard are usually indicated by manufacturers in the instructions for roofing coverings.
The lathing for laying the valley can be of the following types:
As already mentioned, a house with a valley roof is subject to loads from rain and snow, which must be removed from its surface in a timely manner. In this regard, arrangement high-quality waterproofing is a top priority. Therefore, when installing a valley, you should pay attention to such subtleties as: correct pruning roofing material, compliance with the pitch between supporting elements and fastenings, tightness of seams, dimensions of overlaps. Only the technology for installing a valley made of soft roofing, which is placed on a continuous base, will be somewhat different.
Installation under soft roof done like this:
The technology for installing a valley under corrugated sheets, ceramic or metal tiles is as follows:
To mark the cutting line, you can use paint cord from KARPO, Irwin, INTERPOOL MT-2507 or STAYER brands.
Installation of a groove for ondulin:
Roof structures such as attic doors or dormer windows also need to be waterproofed. The construction of a valley in such places involves placing its lower element on the correct covering.
The work flow looks like this:
Thus, the valley is an extremely important and necessary element of the roof, which you can arrange with your own hands. It is only important to arm yourself with some knowledge and tools.
Increasingly, the roof has more than just a functional purpose. Often this element is the highlight of the building. Such roofs have many planes that connect at 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.
On roofs of complex shapes, when protruding dormer windows are installed, sharp corners are formed. They are obtained at the junction of two slopes. The junction is called the valley, and the roofs are called valleys.
What is a valley
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. Due to the 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.
Rafters from different slopes in the valley 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.
In places of greatest load (in the widest place), the valley rafter leg is supported from below by a jib.
A support is placed at the bottom at the widest point
At the junction of two roof slopes, reinforced sheathing is required, and its design depends on the type of roofing material:
Lathing is done twice as often
For corrugated sheets, slate and ceramic tiles, two or three boards are needed on each side
Under the ondulin there should be a gap of 15 cm between the two boards
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, requirements for the sheathing, and other technical issues. It is clear that you must adhere to their recommendations.
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
Fastening to the side with clamps
When constructing a valley, the main task is to ensure tightness. From this point of view, the second fastening option is more correct - after it there are no holes left, 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 not everyone is happy with the appearance of the cut sheets. In order to close them there is a decorative overlay, which is called the upper valley. It performs a decorative function - it covers the cuts; quite often it is simply not used.
Made from corrugated sheets and slate
Under these materials, several boards are laid lengthwise in the valley. A strip of waterproofing is fixed to them, which is then connected to a waterproofing membrane fixed to the slopes. The overlap should be at least 10-15 cm, the joints are connected using double-sided tape.
Installation of a valley on a roof made of corrugated sheets
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 valley made of corrugated sheets
You choose the open or closed type of connection of the slopes; the structure of the entire pie remains the same. Only the method of cutting the corrugated board changes.
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.
In the case of ondulin, the sheathing for 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.
A special gutter is placed between the padded boards
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.
The upper fragment of the gutter overlaps the lower one by at least 15 cm
After the entire gutter is laid, the installation of roofing sheets begins. 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.
Ondulin is trimmed twice: first roughly, then precisely
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.
Fastened with special nails
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.
Roof valley: installation, do-it-yourself installation, photo, video
When building a private house, bathhouse or utility buildings, the roof truss system requires a special approach. It is important to perform the calculations correctly and prepare high-quality material for installation.
The calculation of load-bearing structures in construction is usually performed using the limit states method, i.e. at the moment of loss of resistance of the structure under the influence of external loads up to destruction or unacceptable damage.
The rafter system reaches limit state, If:
According to building codes, the maximum permissible deflection of a rafter leg or tie is 1/200 of the length of the element. To ensure high reliability of the structure, it is recommended to design the roof taking into account the maximum permissible deflection of 1/250 of the rafter length.
The calculation of the roof truss structure is carried out taking into account the maximum loads from the side:
To obtain information on the basis of which calculations are made, it is necessary to have:
The cross-section of the timber from which the elements of the rafter structure are made is calculated using a special formula, which takes into account the length of the rafter leg, the pitch between the rafters, and the resistance of the selected type of wood to external loads.
Tables for selecting sections of elements are used when designing simple roofing structures. Developing a roof project of complex shapes requires a professional approach.
The reliability of the truss structure is influenced by the following factors::
The type of rafter system, the presence of certain nodes of elements is dictated:
When building houses with a usable attic or attic floor usually used truss structures with layered rafters. Their main nodes include:
When designing, it is important to immediately decide on the methods of fastening the elements. The choice depends on some of the characteristics of the lumber, as well as the preferences of the people conducting construction work.
Key stages of roof construction
Installation work begins after the preparation of the project, which indicates all the dimensions of the elements and their mutual arrangement, as well as connection principles. In addition, you should purchase and bring the necessary building materials, tools, fasteners, etc.
The principles of constructing a pitched roof, in general, do not depend on its configuration. The work technology includes the following stages:
Laying the Mauerlat. The support beam is laid on waterproofing (roofing felt or other moisture-proofing material), which protects the wood from rotting. To fasten the Mauerlat to the wall, wire embedded in the masonry can be used, or clamps can be used to attract the timber to the anchors in the wall, but preference should be given to studs mounted in a monolithic concrete beam.
The length of the free end of the studs must exceed the thickness of the mauerlat beam by a distance that allows the nut to be screwed on. The studs can be staggered (but not necessarily) with a pitch of at least 2 meters. To prevent the stud from being pulled out of the concrete, its recessed end should be bent.
Installation of front (outermost) rafters. When building a roof truss system with your own hands, it is very important to install the main rafters strictly vertically and at the same level; the correctness of the planes of the slopes and, accordingly, how evenly the load on the roof will be distributed depends on this.
Depending on the chosen roof configuration, at this stage a ridge girder is also installed, which must be strictly horizontal. The run is based on special vertical racks or attached to the gables. If mounted hip roof, key point is the installation of diagonal rafters.
The construction of a roof truss system of complex shape (multi-gable roofs) requires the creation of connections for ridges and slopes. The planes of the slopes can have different geometric shapes: triangle, rectangle, trapezoid. The endova is the junction of the slopes with the formation of a negative angle.
In the house plan, roofs with valleys look cruciform, T-shaped or L-shaped. These are the two main ways to create roof junctions. At the design stage, a roof plan (top view) is drawn up, taking into account attic and dormer windows, all junctions, roofs over terraces or verandas, indicating all linear dimensions. The general plan of the roof is divided into rectangles and squares; the main rooms and extensions are indicated on it.
On the roof plan, the main purlins should be indicated, and in the perpendicular direction, the secondary purlins over smaller rooms should be indicated. Then lines are drawn connecting the corners of the roof above the secondary rooms with the corners of the main roof. These diagonal lines indicate the location of the valleys - the internal corners formed by the junction of the slopes.
When installing a rafter system, the valleys at the joints of roofs of the same height (i.e. if the ridge girders are located at the same level) are diagonal rafters, resting with the upper end on the ridge girder and the lower end on the mauerlat. The installation of such rafter legs is carried out similarly to the installation of diagonal rafters for a hip roof.
Depending on the size of the extensions, the corners roof slopes can have different meanings. The geometry of the roof can be changed by shortening the size of the purlins. The angle of inclination of the valley changes accordingly. The roof truss system with a valley can be made using a spacer or non-spacer method. If spacer rafters are installed, then to relieve excess stress, a horizontal tie should be secured at the bottom of the structure.
Installation of the valley
The design and installation of a roof with valleys is quite complex. In this case, mistakes can lead to roof collapse or leaks. One of the purposes of the valley is to ensure the removal of precipitation. Valleys differ in their design:
To install a valley on mating slopes, it is necessary to install a continuous sheathing. Waterproofing is laid along a wooden gutter - it is better to lay it in two layers. Then the valley is secured with self-tapping screws. If its joints are horizontal, the overlap should be at least 100 mm (recommended value is 300 mm). If the valley is mounted on a slope with a slight angle of inclination, it is recommended to add another layer of waterproofing, and when installing the valley on a metal tile roof, additionally use a self-expanding sealant.
Endova open type easier to install and better removes precipitation. Closed and interlocking structures are typically used on steeply pitched roofs covered with certain roofing materials. Their disadvantages include increased costs for additional waterproofing and some installation difficulties. Intertwined and closed valleys drain precipitation worse, and in cold climates in winter they serve as a place for accumulation and compaction of snow.
Do-it-yourself roof truss system, device with a valley, video
Make a gable or pitched roof quite simple. Although it will perform its main function, it will not be attractive from an aesthetic point of view. IN Lately Designs with several slopes and protrusions are gaining great popularity. At the junction of two slopes, a node is formed, which is called a valley. This part of the roof requires special care during design and installation. From the article you will learn the features of a valley and how to make it yourself.
Only the inner corners of the roof are called the valley. Buildings that form a T or L shape cannot be built without this element. In addition, similar corners are formed in the places where dormer windows emerge, protruding parts of the attic and other architectural delights.
The main task of the valley is to protect attic space from moisture penetration. The fact is that in this place the roof experiences increased loads due to the fact that a large amount of precipitation accumulates there. In winter, snowdrifts form here and the structure can sag under increased loads.
The internal corner is assembled from two planks, and each is created for its own purpose:
The valley material usually matches the main covering on the roof. In some situations, it can be replaced with a sheet of galvanized steel. It is important to choose metal with a protective coating, since it will often have to come into contact with aggressive environments.
When constructing a valley, it is important to follow all the rules for the construction and installation of rafters. If one of them is neglected, then there is a threat of frame collapse. However, the standards differ for various types designs. Depending on the roofing material used, one of two types of frames is used:
Depending on the slope of the slopes, wooden rafter legs are attached to the valley at a certain angle. However, for each side this indicator may differ from the other. Where the beams meet, a thicker rafter is installed. The method of fastening to this place depends on the length of the rafters. If it is less than two meters, then nails are enough, otherwise metal pads will be needed for reinforcement. Before installing the valley, the place of the greatest load is calculated, and a supporting jib is installed there.
Where the slopes meet, it is necessary to strengthen the roof sheathing. How much reinforcement will need to be done depends on the type of roofing:
The main part of the roof valley is attached to sloped rafters, which one side rests on the ridge and the other on the Mauerlat. In some cases, for example, when installing a skylight, the mounting locations may change. Depending on the type of roof, the height and shape of the ridge varies. This applies to both the main and secondary structures.
For change geometric shape It is enough to lengthen or shorten the roof structure. Along with these manipulations, the slope of the valley will change.
The valley rafter system is assembled as follows:
The abutting flanges transfer high compressive stress to the diagonal rafters. Because of this, the beam heavily loads the joint of the mauerlats. To reduce the pressure from the inclined stoprail to the post to which the secondary roof purlin is attached, stretch the connecting tie. It works in tension and does not allow the valley stop to squeeze out the mauerlat. If the roof is hip, then the tie is connected between two diagonal rafters.
In addition, if under some circumstances the main ridge loses its fulcrum, the tightening will act as a thrust. So, it can prevent emergency roof destruction.
The tightening or grip must be placed at the base of the valley, since in a high position it will stop working in tension. In this position, the beams work in compression and are called crossbars.
As you can see, the rafter system for the valley is not particularly complicated and you can install it yourself. At the same time, it is important not to make a mistake in choosing the cross-section of the beam and the reliability of fastening. Then you will assemble a unique roof and it will last for several decades without leaks.
Roof with valley and rafter system: how to install
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 all elements of the roof covering that 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:
At the same time, it is the additional elements that require the most careful, responsible approach to installation, since they often take on most of the load for draining or removing 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 is a general concept that defines 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.
Valleys (in a general sense) are of three types:
The second and third types are much less common, since their construction requires workers with experience and specialized knowledge. At large selection roofing materials commercially available and different properties and the specifics of installation, it is not easy to find people who know how to design complex roofing elements. In addition, all work is carried out in difficult conditions, at heights, 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 essence, comes down to achieving a purely decorative effect, which often means a waste of time and labor.
Valleys as an additional element are also divided according to the method of installation:
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
For the manufacture of valleys, the same material is used as for the main one. coatings - asbestos cement is used for slate, for metal tiles or corrugated sheets - 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.
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.
The rafter system at the transition points of one plane to another must provide straight and even lines without depressions or distortions that could cause incorrect installation valleys.
The device for connecting two valleys on a slope can be of the following types:
Rafter system for the valley
For correct and precise installation of rafters First of all, you need to designate the runs - the lines connecting the planes. This is done using a stretched rope between the two extreme points of the run and is oriented along this line when assembling. With due care and attention, the design turns out smooth and suitable for performing its functions.
An important element of the valley rafter system is the sheathing. At the junctions it is made continuous, with mandatory waterproofing. 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 rapid failure of the bar. If we take into account the presence of a layer of insulation and waterproofing, sheathing inner surface attic space, other finishing coatings, detection of damage to the planks will not occur immediately.
By that time, significant damage will have been caused due to water penetration into the roofing materials and elements of the rafter system. Replacing the strip will also require serious work, as well large quantity time.
How to install the additional element correctly:
How to make a roof valley
All connections are made using roofing screws equipped with a gasket made of special wear-resistant rubber. All areas of possible leaks are treated with sealant.
In addition to valleys, other roofing elements are also manufactured. Any area that requires additional design has a corresponding additional element.
Exist the following types additional elements:
So, we have fully answered the popular question - what is a valley and how to install additional material correctly. All elements have clearly defined functions, their use is an important and irreplaceable stage in the construction of a roof. Most often, attempts to somehow replace ready-made additional elements with handicraft or non-standard parts lead to design inconsistencies and failure to fulfill their purpose. Saving in this case leads to large losses later.
Design and functional features of the valley - ensuring effective drainage and aesthetically pleasing 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.
Valley - what is it (photo), installation of the connection of two valleys on the slope (upper and lower), installation of sheathing and rafters