Water resistance of Hilti Firestop products

Transcription

1 Water resistance of Hilti Firestop products The enclosed pages are taken from the Brochure Water Resistance Edition 2006 Please note the tables in this extract may be out of date For Material Safety data sheets visit the technical library at Hilti (Gt Britain) Ltd TECHNICAL ADVISORY SERVICE TELEPHONE Quality Management System Certification Standard: ISO 9001:2008 Issued by: The Swiss Association for Quality and Management Systems SQS. Registration No: (The current certificate can be downloaded from Field of activity: Market Organisation. Note: The certificate of Hilti (Gt. Britain) Ltd. is a sub-certificate to the master certificate of Hilti Aktiengesellschaft,FL-9494 Schaan with the field of activity: Research, Development, Manufacturing, Sales and Service. Hilti (Gt. Britain) Limited, 1 Trafford Wharf Road, Trafford Park, Manchester M17 1BY Telephone:

2 30 YEARS Contents Hilti Firestop systems Water resistance pages YEARS Standard details showing the assembly required to obtain the required acoustic performance can be found in the product details in the Hilti Firestop specifiers binder or can be downloaded from the technical library. CAD files of the standard details FS ***-** can be downloaded from the technical library at Revision History June 2011 May 2013 First release Update Hilti (Gt. Britain) Limited, 1 Trafford Wharf Road, Trafford Park, Manchester M17 1BY Telephone:

3 Contents 1. Introduction 3 2. Terms used 4 3. Rain resistance 6 4. Mould and mildew 7 5. Water tightness 8 6. Tested systems from Hilti 9

4 1. Introduction Water resistance is understood by Hilti to mean a construction material s ability to withstand the effects of water and moisture not only in the completed, occupied building, but also during the construction phase. During the construction of the shell of a building, before it is fully sealed and weatherproof, entire floors may be flooded by rainwater. Inadequately hardened sealants may be washed out. These products therefore require a certain degree of rain resistance. In rooms where humidity is high there is a risk of mould or mildew forming even after a firestop product has hardened. In the event of the formation of mould, this must have no negative effect on the intended function of the firestop product. Fireproofed penetrations are expected to provide a certain degree of water tightness in order to minimize consequential water damage in the event of accidents (burst water pipe, fire extinguishing water). A firestop system s water resistance is therefore an important characteristic in addition to its main function. Hilti firestop systems are therefore not only tested and approved internationally in accordance with passive fire prevention requirements, but also in terms of their water resistance in accordance with the applicable standards. This brochure, on the one hand, is intended to point out the general principles of water resistance and, on the other, to provide information, based on practical examples, on the applications for which Hilti firestop products are used. page 3

5 2. Terms used Rain resistance Joints and penetrations require to be fireproofed even in buildings where construction of the shell is not yet complete. In the event of water finding its way into the building immediately after firestop products are installed, recently applied sealants or firestop coatings may be washed out. Users thus need to know how long it takes for such firestop products to dry and harden sufficiently so as to be no longer susceptible to damage by water or rain. DIN describes a test setup which allows the rain resistance of sealants and coatings to be determined with reproducible results. Mould and mildew Mould in a building can attack and weaken many types of building materials. Moreover, fungus releases spores which are detrimental to the health of residents or users of the building concerned. Even in situations where it is not the origin of the fungus, the firestop system still has to be protected effectively. The fungus resistance of the various Hilti firestop systems is tested with the relevant types of fungus in accordance with the international standard ISO 846 and US standard ASTM G21. Water tightness This is understood to mean the temporary water tightness of the firestop systems. This characteristic is important with a view to minimizing the consequential damage caused by water in the event of an accident (fire extinguishing water, burst pipes). In accordance with the US standard UL 1479, the firestop systems are subjected to a pressure approx. an 1 m (comparable to 3 feet) water column for a certain time in order to determine whether the firestop system is capable of withstanding this pressure. Rain resistance Water tightness Mould and mildew page 4

6 3. Rain resistance Joints and penetrations need to be sealed to prevent the spread of fire even while construction work on the shell of a building is still in progress. Rain may enter the building during this early stage of construction. Freshly applied water-based sealants or coatings may be washed out if rain falls on them before their surface has dried and hardened. This possibility cannot be ruled out, especially where curtain walling is to be installed and sealed appropriately. The gap between the facade section and the floor deck is first filled with mineral wool and subsequently sealed with a firestop system coating. If rain falls on the floor deck above, water may drip directly onto the freshly applied coating and the mineral wool on the floor below. Facade application Testing for rain resistance The rain resistance of water-based sealants is specified in the DIN standard. The standard requires that the sealant to be tested is applied to a test specimen and then allowed to dry for a certain period before being exposed to "rain for 10 minutes at a pressure of 2 bar. The difference in weight of the specimen before and after exposure to the rain is subsequently determined and a visual assessment made. Results The following Hilti firestop systems have been tested in accordance with DIN 52461: Hilti firestop system Rain resistant CP 601S elastic firestop sealant Immediately CP 604 self-leveling firestop sealant Immediately CP 606 firestop joint filler After 1 hour CP 672 firestop joint spray After 4 hours CP 670 / CP 673 firestop coating After 3 hours Test setup for CP 672 firestop joint spray page 5

7 4. Mould and mildew As a consequence of the introduction of more stringent energy-saving regulations for buildings, the envelope of buildings are today being increasingly tightly sealed against moisture and draughts. Moreover, modern dispersion paints and wall coverings with a high plastics content (PVC wall coverings) form a barrier which greatly reduces water vapor diffusion. As a result, complaints about attack by fungus at points where thermal bridging occurs, such as at windows or doors, are becoming increasingly common. Measures to successfully prevent the formation of mould and mildew in a building must be taken right at the planning stage. This must also include the correct choice of components and materials and these must be used and installed correctly. The formation of fungus Fungus spores can be found almost everywhere. The following conditions encourage the growth of fungus: Warmth and dampness (20 35 C, 60 85% relative humidity) Permanently damp areas A nutrient on which the fungus can grow, e.g. materials such as wall coverings, wood, textiles, plastics and rubber. Under normal conditions of use, fungus in buildings typically occurs in cellars, bathrooms and kitchens or at thermal bridges, e.g. around doors and windows. The level of moisture in a building may increase as a consequence of some exceptional incident such as water ingress due to flooding, burst pipes or after activation of sprinkler systems. The formation of mould and mildew in buildings page 6

8 The effects of fungus There are various types of fungus. Some are seriously detrimental to the health if their occurrence is on a large scale. Examples of these are: A few species of the Penicillum group Some species from the Aspergillus group Occupants of rooms where fungus is present often suffer headaches, eye irritations and symptoms similar to those of the common cold. Persons of a certain disposition may suffer allergic reactions if the spores are inhaled over a long period. In extreme cases, buildings attacked by fungus may no longer be inhabitable and may even have to be demolished. An additional problem is posed by the fact that fungus uses building materials as a nutrient. This means that the fungus attacks the materials where it occurs. In mild cases, the material concerned may become discolored, while in extreme cases the attack can cause a change in the technical properties of the material (e.g. strength, conductivity, elasticity). Close-up showing the Aspergillus niger fungus How can the growth of fungus be prevented? In a three-person household, the water vapor released by the inhabitants themselves (30 to 100 g/h per person) and through showering, washing, and cooking as well as by plants and other sources of moisture, adds up to a total of between 6 and 14 kg of water vapor released each day. Similar levels of moisture also occur in factory areas or in offices. Approximately 250 m 3 of air must be moved in order to transport away 10 kg of water vapor from the interior of a building. This means that the air in the rooms concerned has to be exchanged approximately every 2 3 hours in order to transport away the undesired moisture. Other helpful everyday steps to be taken include ensuring that the rooms are adequately heated (approx. 20 C). In absolute terms, warm air is capable of absorbing more water vapor than cold air. This reduces the amount of condensation at thermal bridges. Appropriate measures should also be applied to the structure of the building in order to avoid or reduce thermal bridging. Protection of building materials Various measures can be applied to protect building materials from attack by fungus. In principle, 2 approaches are conceivable: a) Prevent the formation of fungus on the product b) Ensure that the product is not attacked by the growth of fungus on it and that its functionality (fire protection) is not compromised The formation of fungus on products used in construction can be effectively prevented by the addition of fungicide. This additive, however, can be leached out of the product by water or moisture during the course of time. A further problem is presented by the fact that most fungicides are hazardous to the health. The applicable concentration is therefore kept as low as possible or, as an alternative, a substance which can be integrated in the chemical matrix of the product is used. Accordingly, the optimum solution would be a product which, due to the use of suitable materials, provides no nutrition for fungi and is therefore not at risk of being attacked. Products of this kind require no protective fungicide. This is the approach followed by Hilti in the development of new firestop systems. page 7

9 Tests to determine fungus resistance In order to verify that Hilti firestop system products are effectively protected against attack by fungus, an independent test institute was commissioned by Hilti to conduct tests following the principles of the ASTM G 21 and ISO 846 standards. Tests with the following 2 fungi were carried out: Aspergillus niger Penecillum funiculosum Specimen with sourrounding barrier halo Both of the these fungi are aggressive types which grow extremely quickly. They may release substances that are hazardous to the health and thus present a risk to the occupants of the affected building. In both tests, ASTM G 21 and ISO 846, the test specimens are stored for 4 weeks on a nutrient-free mineral salt solution (Agar A) which has been sprayed with the applicable fungus spores. This means that only the product specimens may provide nutrients for the fungus. The product will not be overgrown by the fungus if it provides no nutrient. In this case, the product can be said to possess fungus resistance. Specimen not overgrown For the ISO 846 test, the specimens are stored on a nutritious solution (Agar B) containing glucose, which has also been sprayed with spores. In this case, the fungus can grow even when the product specimens provide no nutrition. It is thus much more difficult to obtain good results in this test. The products tested in this situation are said to have a fungistatic effect. In this test, fungicide is particularly effective in preventing growth of fungus on the specimens. If the fungicide is leached out of the product, a so-called barrier halo, i.e. a fungus-free zone, forms around the specimen. Subsequently, the material of the Hilti firestop product is also assessed for its fitness for use. The surface of all specimens exposed to fungus is examined under a microscope for signs of damage. Specimen overgrown Test results and their interpretation Hilti has had all relevant Hilti firestop systems tested in accordance with ISO 846 and ASTM G 21, using the nutrient-free Agar A solution. In these tests, no fungus grew on any Hilti product. This means that all of the Hilti firestop systems tested cannot be attacked or damaged by fungus and that they remain functional despite exposure to fungus. Detailed results are available from the original test certification. Summary 1. Fungus does not originate on Hilti firestop systems. 2. The Hilti firestop systems tested are adequately protected against serious damage by fungus. 3. If a building attacked by fungus is to be rehabilitated, the firestop systems must also be checked during the course of the work and cleaned or replaced as necessary. 4. Suitable measures must be taken to combat the cause of the fungus. page 8

10 5. Water tightness Firestop systems help to prevent the spread of fire to other sections of a building in the event of a fire breaking out. However, the resulting losses can be greater and the damage more severe because of the water used by firefighters or water released by the sprinkler system. The extinguishing water can find its way through penetrations for cables and pipes in walls or floor decks, causing damage in additional rooms. There is also always the risk of a burst pipe in a building. The purpose of this internal test is to verify that selected Hilti firestop systems provide water tightness against a 1m water column pressure for a limited period of time. In other words, the test shows that Hilti firestop systems are capable of preventing water ingress in adjoining rooms or sections of a building In order to ensure water tightness, it is essential that Hilti firestop systems are installed correctly in accordance with the Hilti installation instructions. page 9

11 Test setup The test is carried out in accordance with the principles of UL 1479, W-rating (official US test standard). A block of concrete is cast with a centered, square opening. The dimensions of the block are 40 cm 40 cm 10 cm. The dimensions of the opening are 18 cm 18 cm. CP 601S over the opening The opening is sealed with the firestop product, Hilti CP 601S firestop sealant in this case, in accordance with the firestop approval regulations. A plexiglas tube with an internal diameter of 29 cm is then fastened to the concrete block. The seal between the concrete and the aluminium flange holding the plexiglas tube is provided by Hilti CP 619 firestop sealant. The plexiglas tube is then filled with colored water and checked daily for leakage. CP 601S with the flange and Perspex tube The results and their interpretation The test is considered failed if water leaks through the firestop system. Slight traces of dampness, especially on the concrete, do not indicate failure. This test is not suitable for the purpose of verification of the general water tightness of Hilti firestop systems, as is required, for example, for service entries in exterior walls. Interpolating of the results to higher pressures or longer testing times is also not permissible. Key: 1 m water column Water (colored) Test specimen page 10

12 6. Tested systems from Hilti Product Rain Mould Water tightness resistance and mildew CCP 601S CP 604 CP 606 CP 611A O CP 612 (FS-One) O CP 617 electrical outlet boxes O CP 620 O CP 632 O CP 636 O CP 637 O CP 638 O CP 643N / CP 644 O O CP 645 O O CP 648 O O CP 657 O CP 670 / CP 673 CP 672 CP CP 619 O CP 680 / CP 682 O O = tested O = not relevant This brochure was produced by Hilti Corporation, LI-9494Schaan, Principality of Liechtenstein. page 11