1、BRITISH STANDARD CONFIRMED AUGUST 1983 BS 4315-2: 1970 Incorporating Amendment No. 1 Metric units Methods of test for resistance to air and water penetration Part 2: Permeable walling constructions (water penetration) UDC 69.022.32:620.162.4BS4315-2:1970 This British Standard, having been approved b
2、y the BuildingDivisional Council waspublished under the authorityof the Executive Boardon 30 April 1970 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference B/105 Draft for comment 69/816 ISBN 580 06170 1 Co-operating organizations The Committee responsib
3、le for the preparation of this British Standard includes representatives from the following Government departments and scientific and industrial organizations: Agrment Board Asbestos Cement Manufacturers Association British Ceramic Research Association British Precast Concrete Federation British Sto
4、ne Federation British Woodwork Manufacturers Association Cement and Concrete Association Insulation Glazing Association Metal Window Association Limited Ministry of Public Building and Works Ministry of Public Building and Works Building Research Station National Federation of Building Trades Employ
5、ers National Federation of Roofing Contractors Royal Institute of British Architects Timber Research and Development Association Welwyn Hall Research Association Amendments issued since publication Amd. No. Date Comments 4207 March 1983 Indicated by a sideline in the marginBS4315-2:1970 BSI 09-1999
6、i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Apparatus 1 4 Preparation of specimens 2 5 Test procedures 4 6 Recording of results 4 Figure 1 Test apparatus 7 Figure 2 Method of collecting leakage from single-leaf panels (Method C) 8BS4315-2:197
7、0 ii BSI 09-1999 Foreword This standard makes reference to the following British Standards: BS 3763, International system (SI) units. BS 6232, Thermal insulation of cavity walls by filling with blown man-made mineral fibre Part 1: Specification for the performance of installation systems. This Part
8、of this British Standard, prepared under the authority of the Building Divisional Council, sets out methods of test for measuring the resistance to water penetration of permeable walling constructions without open joints. The pressure-box type of test chamber as specified in Part1of this standard, “
9、Windows and gasket glazing systems”, was chosen partly because of its simplicity and partly because this type of apparatus was being used by the laboratories associated in the Working Group on Rain Penetration of the Conseil Internationale du Btiment (C.I.B.). Test procedures should be selected to g
10、ive results which can be related to those obtained under natural exposure. A pressure for test purposes is specified but for further guidance reference should be made to BRE Digest No. 127, “An index of exposure to driving rain” should other test pressures be required. These test methods should not
11、be used to compare the relative merits of walls constructed with materials having different absorption capacities. For example, walls constructed with high absorption fired-clay bricks may give worse results than would be found in practice, whereas the converse may be true for walls constructed with
12、 low absorption fired-clay bricks. It is also difficult to apply the results of the test to walls of considerably greater height than the test panels. In general, test method C (see6.4) is appropriate when the apparatus is used to assess the resistance to water penetration of the external leaf of a
13、test panel of cavity construction. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summar
14、y of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 8 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS4315-2:1970 B
15、SI 09-1999 1 1 Scope This Part of this British Standard specifies methods of test for measuring the resistance to water penetration of permeable walling constructions without open joints under static air pressure. The methods are applicable to constructions which can be built in or fixed into a rigi
16、d steel frame by means of which the wall panel can be transported and secured to the pressure-box test equipment. The first method is also applicable to walling constructions, not built into a steel frame, provided an air-tight seal can be made between the pressure-box and the front face of the pane
17、l. Three methods of recording the extent of water penetration are specified, i.e.: Much of the test apparatus and procedure is common to all three methods but where it is particular to one or two of them only, the letters A, B or C are inserted after the relevant clause numbers to indicate their abi
18、lity to a particular method of recording water penetration (see above). These test methods are not recommended for comparing the relative merits of walls constructed with materials having different absorption capacities (see foreword). 2 Definitions For the purposes of this Part of this BritishStand
19、ard the following definitions apply: 2.1 open joint a deliberate open discontinuity between two units in a walling construction 2.2 specimen the test panel, which may either consist of a single unit or a series of units without open joints. The front face of the specimen is that facing the pressure
20、chamber 2.3 test area that part of the specimen, together with masking material and in-fill material where used, exposed to the test conditions 3 Apparatus 3.1 Pressure chamber. The test chamber shall be an airtight box capable of withstanding the test pressure. One of its vertical sides shall be le
21、ft open so that the specimen can be secured to this side with the front face of the specimen towards the inside of the chamber. The attachment between the specimen and the chamber shall be made with bolts or any other suitable means which can withstand the test pressure. If the specimen is in a stee
22、l frame, the test chamber shall be attached to the flange of the steel frame. A gasket between the box and the steel frame or between the box and the face of the free-standing panel shall ensure an air-tight joint. 3.1.1 At least one observation window shall be provided in the test chamber to enable
23、 the front face of the specimen under test to be viewed. A door may be fitted to the side of the test chamber to provide access to allow any necessary adjustment; alternatively, the adjustments can be made through the observation windows if they can be opened. 3.1.2 The bottom of the test chamber sh
24、all be fitted with an outlet which will allow the water to run away to waste. The outlet shall incorporate a trap so as to provide a depth of water seal at least sufficient to maintain the desired air pressure within the chamber. 3.1.3 The size of the chamber shall be such as to provide a test area
25、of at least1m 1 m. An apparatus suitable for testing a wide range of walling constructions is shown inFigure 1. Where the apparatus is used to test resistance to water penetration of blown man-made mineral fibre cavity insulation, the panel area shall be at least3.5m high by3.0m wide. (SeeBS 6232-1)
26、. 3.2 Air supply system 3.2.1 Air shall be passed into the chamber to maintain the specified pressure (see Clause5). Direct draught on the face of the test specimen shall be avoided and to accomplish this it may be necessary to fit a baffle over the end of the air inlet pipe. 3.2.2 Provision shall b
27、e made to measure the air pressure difference between the inside and the outside of the test chamber, that is, across the test area, to an accuracy of 10 N/m 2( 1 mmH 2 O). Method A. Recording, by time-lapse photography, the increase in area of dampness. Method B. Recording the change in weight of t
28、he specimen. Method C. Collecting and recording the amount of leakage through the specimen.BS4315-2:1970 2 BSI 09-1999 3.3 Water spray system 3.3.1 The water spray system shall be designed to apply a uniform horizontal band of spray not more than250mm deep at the top and across the width of the test
29、 panel. The band of spray can be obtained from spray jets placed along a horizontal feed pipe set at a suitable distance from the wall face. 3.3.2 A valve shall be inserted into the supply pipe so that the rate of flow of water can be controlled. The rate of flow and the quantity of water used shall
30、 both be measured. 3.3.3 To obtain intermittent spraying, the flow of water shall be controlled by a second valve, which is time operated, for example by an electromagnetic valve operated by a time switch. 3.3.4 A fine filter shall be included in the line to prevent particles from blocking the spray
31、 jets. 3.4 Steel frame 3.4.1 The frame shall consist of steel channel bolted together and with supports welded to the bottom frame member to which channel section feet are bolted to hold the specimen vertical. The frame shall consist of steel channel bolted together (e.g.152mm 76 mm channel for spec
32、imens up to150mm thick or229mm 76mm channel for specimens up to225 mm thick) and shall incorporate a means of retaining it in a vertical position, e.g. by channel section feet fixed to the bottom member. Thicker specimens can be accommodated by bolting two frames together or by bolting an additional
33、 steel section to the bottom frame member only. If attachment between the test chamber and the frame is with bolts, the flanges of the frame shall be suitably drilled. Sufficient clearance shall be provided in the holes to ensure that the test chamber shall fit any frame. 3.4.2 Rings shall be attach
34、ed to the top member of the frame to enable the wall to be lifted and weighed. They also enable the top frame member to be removed after un-bolting since this may be necessary during the final stages of building the walling in the frame. Where provision is made for lifting the wall by an attachment
35、to the top of the frame, it is essential to provide a top frame member rigid enough to withstand distortion. 3.5 Photographic equipment (Method A). The equipment shall comprise a recording camera and suitable lighting to record the extent of water penetration by time-lapse photography. A clock and a
36、 board on which are given details of the test, including the time and date of starting the test, shall be placed so as to appear in the photographs. The clock should preferably be a direct reading digital clock indicating a24hour day and show the day of the week and/or the date. The camera and light
37、ing shall be controlled by time switches. 3.6 Weighing equipment (Method B) 3.6.1 Sufficient lifting and manoeuvring facilities shall be provided for moving, placing and weighing the frames and wall panels. All movements shall be so gentle as not to damage the panels. Care must also be taken to avoi
38、d racking when setting down specimens. 3.6.2 The weight can be measured by, for example, a crane-hook weighing machine of the steelyard type. The weighing equipment shall be capable of recording a change in weight of 1 % of the total increase in weight expected in the course of the test. If it is ne
39、cessary to follow the absorption of water during the course of the test, the weighing machine should be capable of weighing the walling in its frame and the test chamber also, unless the test chamber is easily and quickly detachable from the specimen. When the specimen and the test chamber is weighe
40、d during the course of the test, it is essential that it is kept vertical and a rigging screw device shall be provided between the hook and the test chamber to permit correction of the eccentric load put on the frame and specimen by the test chamber. 3.7 Collection and measurement of leakage (Method
41、C). Provision shall be made for collecting and measuring the amount of water penetrating the specimen. 4 Preparation of specimens In all cases the construction of the walling shall be adapted to the material under test. The test specimen should preferably be of such size that it can be constructed b
42、y the method normally used for the material. For brickwork and blockwork the dimensions of the area of the specimen exposed to the spray shall be not less than1m 1m. For other walling constructions a similar area of specimen exposure should be selected whenever possible.BS4315-2:1970 BSI 09-1999 3 4
43、.1 Preparation of specimen for time-lapse photography assessment (Method A) 4.1.1 A transportable panel of unit masonry built in a steel frame as described in3.5 or a precast panel erected in a frame shall be built or erected on a damp-proof course sealed to the bottom frame member with mastic. Pene
44、tration at the edges of the panel shall be prevented as far as possible by, for example, two strip (divided) mortar joints up the sides and across the top. For panels of unit masonry built in a frame, the top member of the frame shall be removed to lay the final courses of masonry, etc., and shall b
45、e replaced and bedded down on the divided mortar joint at the top of the specimen. Where precast panels are to be tested the top frame member shall be removable for panel erection purposes and subsequent sealing between the top of the panel and the frame. The seal around the edges on the front face
46、can be completed by covering with a strip of mastic impregnated fabric tape or other sealing tape and for this the mortar joint between the specimen and the frame is left flush at the front. This sealing tape should be about50mm wide and overlap the steel frame by about12.5mm and the masonry units b
47、y about25mm. Alternatively the seal can be completed with a fillet of bituminous or other suitable mastic and for this the front edges of joints should be raked out to a depth of from8mm to10mm. If the specimen does not occupy the whole of the area within the frame, the remaining space should be fil
48、led with some impermeable in-fill material, and suitable seals should be made between the specimen, the in-fill and the frame. 4.1.2 Transportable panels of sufficient intrinsic strength may not require to be built into steel frames. The test is applicable to these and to other free-standing wall pa
49、nels provided a sufficiently airtight seal can be made between the pressure-box test equipment and the front face of the test area. 4.1.3 Sub-division of a panel is not desirable but when a panel is sub-divided so that two or more materials can be examined in the same test, these shall be separated as completely as possible vertically with, for example, a damp-proof course or other impervious membrane. 4.1.4 Specimens shall be allowed to dry naturally in the laboratory at a temperature of from10 C to25 C and from40% to70% relative humidity for at least14d
