Treatment of condensation in sandwich panels without known vapour resistance of sealant

Abstract

In order to calculate amount of interstitial condensation in a building envelope, water vapour resistance of each layer is of importance. Once having it, 1D calculation according to ISO 13788 with monthly average vapour pressures can be applied. In EN 14509 sandwich panels are considered to be impermeable for water vapour, thus (according to the standard) water vapour cannot enter from outside and condensate in the panels. But it is not always true for real sandwich panels, because joints between neighbouring panels can cause non-neglecting water vapour bridges. Although in measurements of linear water vapour transmittance of the joints (Ψv) stationary boundary vapour pressures can be applied, the measurements can be long lasting. We shortened time needed to get Ψv performing simulations in Delphin6.0. We simulated panels and steel sheets with joints using constant boundary vapour pressures and compared the results with the results of measurements on the equivalent systems. In systems under consideration a sealant in built-in-state, located at a joint of a sandwich panel, is a compressed EPDM tube. It is impossible to directly measure its effective μ according to ISO 12572. In the paper we study to which precision it is possible to determine it using measurements and simulations. Once having effective μ of the sealant (if all other necessary material parameters available) one can simulate condensation in envelopes including sandwich panels in 2D according to EN 15026 using hourly climatic data. Another goal of the study was determination of differences in resulting Ψv values when varying narrowest part of the gap dGAP at the joint in the panels without any sealant. Results confirm significant sensibility of Ψv to variations of dGAP.

Keywords

kondenzacija vodne pare;difuzija vodne pare;numerične simulacije;upornost difuzij vodne pare;linijska prepustnost za vodno paro;water vapour condensation;water vapour diffusion;numerical simulations;water vapour resistance;linear water vapour transmittance;sendwich panels;

Data

Language:	English
Year of publishing:	2020
Typology:	1.08 - Published Scientific Conference Contribution
Organization:	ZAG - Slovenian National Building and Civil Engineering Institute
Publisher:	EDP Sciences
UDC:	536
COBISS:	30516739
ISSN:	2267-1242
Views:	38
Downloads:	15
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Slovenian
Secondary keywords:	kondenzacija vodne pare;difuzija vodne pare;numerične simulacije;upornost difuzij vodne pare;linijska prepustnost za vodno paro;
Source comment:	Nasl. z nasl. zaslona; Opis vira z dne 30. 9. 2020; Št. prispevka: 07007;
Pages:	str. 1-7
DOI:	10.1051/e3sconf/202017207007
ID:	23073818