Waterproofing of roof with bitumen roof shingles

The rainy periods of the year represent a real test for the buildings and facilities that we inhabit and exploit. The harmful effects of leaking water, condensed water vapor, the rising capillary or frozen moisture in the structure, predict destructive consequences if we do not provide quality protection of the structure.

The waterproofing of buildings and facilities is perhaps the most important, the most responsible and the most difficult part to be implemented in the construction process. The variety of structures, surface and operating conditions require careful examination of all parameters and proper selection of suitable material. Due to its versatility and particularly high waterproofing properties, products made of bitumen-based material are one of the most popular and used in the fight against the moisture. Parts of their proven advantages include the ability for application on various building surfaces, including those with large slope and complex geometry, excellent adhesion to the surface and ease of installation.

Roofs are vivid example of a building structure with complex geometry subjected to severe weather. This material is designed to track the process of waterproofing of roofs with bitumen roof shingles. These type products represent an ideal solution for implementing a finishing coating on lightweight roofs that cannot bear the load of traditional and contemporary ceramic concrete roof shingles. Other advantages are the notable water-repelling properties, easy installation and replacement, if necessary, the low weight and so on.

The process of waterproofing roofs with bitumen roof shingles go through several major phases, namely:

I. Preparation of the base

1. Building a wooden skeleton. On the roof construction is build even, flat, clean and dry wooden planking. It should be made of boards or hydrophobic wooden panels. As such could be used OSB, waterproof plywood, MDF for outdoor use and others.


2. What does it take to built it? For constructing of a planking are only to be used dry boards of the same thickness and width from 2 cm to 15-20 cm. The timber must be sufficiently dry in order to prevent buckling of the boards during their drying. Otherwise it could damage the integrity of the bitumen roof shingles.


3. Quality strengthening of the wooden coating. It must be sufficiently strengthened in order to prevent movements that could damage the roof shingles. The eave is formed with a standard skirt from galvanized steel, stainless steel, PVC or other.


4. Installation of outlets. Before the laying of the roof shingles is started, it is necessary that outlets are positioned and mounted. Their function is to ensure the ventilation of the roof and prevent the formation of condensation.


II. Placing a under-roof lining

Of particular importance for the preparation of the base before lying the roof shingles is the protection of the roof construction from external influences. This is done by placing under-roof membrane. It protects the under-roof space from rains and thus it serves as an additional protection. The use of under-roof lining reduces to great extend the problem where the unevenness in roof lining leave a visible mark in the bitumen roof shingles.

The lining is applied in parallel to the eave strips, which then are nailed into the wooden coating. It starts from the bottom, each subsequent (upper) overlaps with the lower with 10 cm. Strong nails are to be used for the nailing.

IMPORTANT: It is installation is extremely quick and easy. We do not recommend you to skip this stage of the construction of the roof system, in order to ensure its operational quality and good results in the future! In roofs with slope below 20° is recommended the use of special lining.

III. Placing of bitumen roof shingles. 

1. The placing of bitumen roof shingles starts from the eave. Something specifically about it, is that it should be formed with a standard lining (skirt) from galvanized steel, stainless steel, PVC or other.




2. The initial stripe is made by cutting the tail of the tile. The flat part must be even with the front board or to cover the roof gutter.




3. The second line completely covers the first one, being nailed and glued entirely. Thus, the strip of roof shingles appears as the first layer, whereas the tails serves a second one.




4. The bitumen roof shingles must be placed offset, which leads to the need of their laterally shortening by about half a tail. The separate elements must overlap with each other. The formation of diagonals contributes to the rapid drainage and strengthens the entire structure.

5. The striped are nailed at regular intervals with zinc-coated or galvanized nails with wide head. The nails are hammered on top part of the strip, which joints the beaver tails and pass through the upper and lower layer of the bitumen roof shingles. When the roof slope is greater than 60° or at severely windy areas an additional hammering is done by placing not one, but two nails.



6. The mutual bonding of the individual elements is mandatory! The bitumen roof shingles are completely self-bonding on one another under the influence of the temperature from the sun rays. In this way the chance that the wind will raise their ends and damage the strength of the construction is prevented. If within 24 hours after the installation they have not bonded (due to cold weather or another factor), they should be carefully heated with a burner and bonded together.


7. Under the beaver tails located at the ends of the roof structure is applied bitumen sealant TERAFLEX® BITUMEN or bitumen pasta HIDROZOL® BP. When operating in cold weather it can also be used bitumen sealant or bitumen pasta for more stable bonding of the roof shingles to one another.

8. For designing the chimney from galvanized steel or suitable material are made angular segments which are then glued with bitumen sealant or bitumen paste to the chimney. Only at the upper part of the horizontal section these segments are hammered on each strip of roof shingles that is reaching to the chimney.    
The next (upper) strip of bitumen shingles overlaps with the horizontal part of the segments and is bonded tightly on them. At the end of the vertical part of the chimney is put on tin plating, which covers the vertical part of the angular segments. The connection wall-roof is formed in the same way as they are covered with tin plating.

9. The ridge is designed as a projecting part and the last row of roof shingles is turned towards it in order to protect it, after which is hammered. The same is done with the projecting part of the roof shingles on the other side of the ridge. The ridge elements are formed by cutting single beaver tales and hammering them along the ridge with two nails in the area which is going to be overlapped with the next ridge element.


10. The roof valleys (the place where the two roof planes are forming a groove) are formed as on the bottom is placed underlay from bitumen membrane or other type of waterproofing tape with a width of 100 cm. The tape is hammered to the roof lining of a distance greater than 30 cm. from the center of the roof valley. The shingles are placed intertwined on both sides (giving an effect similar to zip) as they are overlapping with 30 cm. inside from the center of the roof valley. After that they are bonded to the waterproof tape by heating with burner and hammered with nails at 30 cm. from the center of the roof valley.


IV. What to look for when laying bitumen shingles.

1. Laying the bitumen shingles must be done in dry and sunny weather with temperatures above +5ºС and air humidity below 80%.

2. The bitumen shingles are laid on roof structures with slope of 12° to 90°, on wooden planking.

3. The mutual bonding of the individual bitumen elements is mandatory!

4. The arrangement of the roof shingles must be chess-like and double layered: the tail is serving as upper waterproof layer and the strip as a lower one.

5. All additional elements of the roof - linings, vents, roof valleys and others are mandatory installed before placing the bitumen roof shingles.



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