BS/EN 495-5-2013 pdf download.Flexible sheets for waterproofing Determination of foldability at low temperature Part 5: Plastic and rubber sheets for roof waterproofing.
This BS/EN 495-5 specifies a method for the determination of the behaviour of plastic and rubber sheets for waterproofing to folding after exposure at a low temperature.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (Including any amendments) applies.
EN 13416, Flexible sheets for waterproofing — Bitumen, plastic and rubber sheets for roof waterproofing — Rules for sampling
[N 1849.2, Flexible sheets for waterproofing — Determination of thickness and mass per unit area — Part 2:
Plastic and rubber sheets
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
top surface
upper side of the sheet, as used in situ
Note 1 to entry: It is usually the inside of the roll.
3.2
bottom surface
lower side of the sheet, as used in situ
Note 1 to entry: It is usually the outside of the roll.
3.3
overall thickness
thickness of the sheet excluding any surface profile
Note 1 to entry: See EN 1849-2.
4 PrincIple
The principle of the test is to place the looped test specimen in an adequate folding apparatus. Expose the looped test specimen to a specified low temperature for 1 h. Close the folding apparatus within 1 s and maintain this position for minimum 1 s. Allow the test specimen to warm to room temperature and examine the folded area under 6 x magnification.
5 Apparatus
The testing equipment consists of parts indicated in 5.1 to 5.3.
5.1 Folding apparatus
Metal folding apparatus or instrumented apparatus with adjustable parallel plates. (See Figure 1 for examples
of such apparatuses.)
5.2 Conditioning room
Cold chamber with air circulation, adjustable at temperatures down to – 45 °C with an accuracy of ± 2 °C.
5.3 Inspection tool
Magnifying glass with six times magnification.
6 Sampling
Samples shall be taken in accordance with EN 13416.
7 Preparation of test specimens
Take four test specimens of 100 mm x 50 mm, two in the longitudinal (L) direction and two in the transversal (T) direction of the sheet for each temperature interval.
NOTE For testing after arlifical ageing, it is possthle to reduce the amount of tested material In this case. take two test specimens of 50 mm x 25 mm in one direction of the sheet for each temperature interval.
8 Procedure
8.1 Temperature
All operations at this procedure outstde the cold chamber shall be performed at a temperature of (23 ± 5) C.
8.2 ThicknesS
Measure the overall thickness of each test specimen according to EN 1849-2. It the ettective thickness is within the declared tolerance, the declared thickness of the product or the measured thickness of the specimen can be used to adjust the plates.
8.3 Looping
Loop the test specimen Iengthways and fix the ends together, for example with adhesive tape. Fold one L and one T test specimen so that the top surface of the sheet forms the outside of the loop. Similarly fold the other two L and T test specimens so that the top surface of the sheet forms the inside of the loop.
8.4 Plate distance
Adjust the distance between the plates of the folding apparatus at a value of three times the test specimen’s
overall thickness (see 8.2). Check the distance between the plates in four points as indicated in Figure 1.
8.5 Position of test specimen
Place the looped test specimen in the apparatus with the taped edges parallel to the hinge of the folding plate as indicated in Figure 1. Place the open folding apparatus with the test specimen in the cold chamber regulated at the specified temperature.
8.6 Folding
After 1 h exposure. close the folding apparatus within 1 s and maintain this position for minimum I s. for example from the vertical position through 9O to horizontal position. This closing p(ocedure takes place in the cold chamber. The temperature of the folding apparatus should not change more than 2 °C within these 2 s.
8.7 Conditioning
Remove the test specimen from the apparatus and allow warming to room temperature (23 ± 5) C.
8.8 Inspection
Examine the test specimen for cracks or fractures In the folded area with the six times magnifying glass.
8.9 Determination of cold folding temperature
The folding procedure shall be repeated at 5 C steps. Fresh test specimens shall be used for each test
temperature.
8.10 Testing of sheets with backing
The samples for sheets with backing have to be taken from the uncoated area, e.g. the area used for welding. Sheets with backing are only tested in machine direction.
If there is no uncoated area (e.g. testing of sheets after uses within a waterproofing system), only the top area should be tested. To adjust the plate, the overall thickness according to EN 1849-2 should be used.
9 Expression of results
When applying the step by step procedure described in 8.9, the cold folding temperature of the sheet is the lowest 5 CC temperature step where none of the test specimens have cracks or fractures.
10 Precision of results
Precision data are based on a Round Robin test involving seven European laboratories. Two types of PVC-p membranes were tested: a PES-reinforced 1,5 mm and a homogeneous bitumen compatible 1,5 mm
membrane. All test pieces were prepared and distributed by one laboratory. All laboratories determined the same values within the 5 °C steps.
11 Test report
The test report shall at least include the following information:
a) reference to this European Standard (EN 495-5) and any deviation from it;
b) all details necessary to identity the poduct tested:
c) information on sampling in accordance with EN 13416:
d) details of preparation of the test specimen in accordance with Clause 7;BS/EN 495-5-2013 pdf download.