Asfaltové stěrky

Pásy

Stříkané polyuretany

Technologie vymykající se zdravému rozumu:
Jako základní charakteristiku můžeme u rizikových technologií považovat zkrácenou životnost ve srovnání se současnými moderními technologiemi kvalitních hydroizolačních materiálů.
Modifikované asfalty a syntetické fólie jsou výrazně méně rizikové než výše popisované technologie a materiály. Nicméně i u nich je možno očekávat nepříjemná překvapení, a to zejména v nejlevnější cenové kategorii těchto materiálů.
Na obrázku je též patrno, jak byl izolační povlak opravován (dodatečný zásyp). Vyplývá z toho, že porucha se časem zvětšuje.

Troubles arising from using risky materials and technology

Over time the meaning of risky technology has changed. In these next words  we tried to make an overview valid for these times. This can´t be completed, but this writing reflects our opinion till 2002.

On our roofs we can find many kinds of technology. Some of these are not in keeping with European standards

•    Oxidized bitumen sheets
•    Modified bitumen sheets with risky modification components
• ·  Synthetic foils that have lost their softness due to evaporating plasticizer
• ·  Spread and sprayed waterproofing on acrylic, polyester and polyurethane bases (over time these materials are expected to improve so that they will no longer  be seen as risky materials).

Some technical troubles are connected with risky technology, which limits the quality and lifetime of the roof.

In all liquid applied technology on the worksite it is a big problem to keep uniformity of technical and geometric properties in all layers. It is especially necessary to have a good and uniform mixture of all parts of the correct thickness as well as a centrally located reinforcement.

Bitumen liquid-applied waterproofing

In the beginning of the 90´s bitumen LAW was produced and was reinforced with polyester or glass fibers (fabric). As protection against UV reflective coating (partly aluminum) was used or the surface was sprinkled with small silicon gravel.

Bitumen felts

Traditional technology with bitumen waterproofing for flat roofs use oxidize bitumen felts with different reinforcements. Like protecting against UV reflective coating is used.

Oxidize bitumen felts come in three different types of reinforcement:

·        Based on burlap, cellulose and other biological material that can decompose. All of these can be categorized under the name IPA. This type of material cannot be used as waterproofing for flat roofs, because  over time these materials go through the process of biological decomposition.

·        Based on aluminum foils. This material is prone to delamination where the aluminum separates from the bitumen layers. Bitumen and aluminum have different dilatational properties dependent on changes in temperature.

·        Based on glass fiber or woven polyester or unwoven. These materials have better technical properties and a longer lifetime compared to older cellulose-based reinforcement

·        A requirement of polyester reinforcement is that it maintains stability in regard to its proportions under all thermal conditions. This material must not become rippled or shift its position.

Sprayed polyurethane

Troubles with loose waterproofing

These troubles arise from low-quality design up to vital errors in design. Poor workmanship or failures of waterproofing in the main area or other structural features. Troubles with loose waterproofing can be divided in to several categories.

Troubles with loose waterproofing arising from design.

·        Choosing risky technologies

·        Choosing incompatible materials and components

·        Choosing impractical technology.

Troubles with loose waterproofing in the main area

·        Worn out waterproofing (maximal lifetime for oxidized bitumen felt are from 10 to 15 years)

·        Use of material with insufficient properties for waterproofing. The material sags and subsequently cracks or breaks due to low durability.  Cracks or breaks can also be a consequence of movement in the underlying support or due to shrinking materials.

·        Warping of the underlying support

Troubles with loose waterproofing in structural features

·        Different characteristics between components and waterproofing can lead to breaks in the main area or in structural features.