Methods to determine whole building hygrothermal performance of Hemp-lime buildings

M Barclay, Neal Holcroft, A Shea

Research output: Contribution to journalArticle

22 Citations (Scopus)
93 Downloads (Pure)

Abstract

Hemp-lime is a potentially useful building material with relatively low embodied
energy and moderate-to-good thermal performance, coupled with good moisture
buffering capacity. However, some uncertainty remains with regards to its in-situ
thermal performance and the capability of building energy simulation tools to
accurately predict envelope performance and subsequent energy demand of buildings constructed of such vapour-active materials. In this paper we investigate the hygrothermal performance of buildings with walls constructed from hemp-lime.
Component-level moisture buffering simulation employing the EnergyPlus simulation tool is found to be within 18% of Wufi Pro analysis and laboratory measurements. The coarseness of component discretization is shown to effect moisture buffering leading to the observation that finer discretization should be employed to improve EnergyPlus HAMT model accuracy. Whole building simulation of the BESTEST building with hemp-lime components indicates that moisture transport inclusion has a large influence on zone relative humidity but little influence on overall heating and cooling demand. A simple effective-capacitance model is able to represent humidity buffering but is less good at representing the response to sudden moisture loading. An additional resistance parameter is added to the model and an IES-ve simulation using this approach is shown to give a close match to the full hygric simulation.
Original languageEnglish
Pages (from-to)204 - 212
Number of pages9
JournalBuilding and Environment
Volume80
Early online date14 Jun 2014
DOIs
Publication statusPublished - Oct 2014

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Hemp
Lime
lime
building
Moisture
buffering
moisture
simulation
performance
Atmospheric humidity
energy
energy shortage
heat pump
Capacitance
Vapors
method
relative humidity
humidity
Cooling
Heating

Cite this

Methods to determine whole building hygrothermal performance of Hemp-lime buildings. / Barclay, M; Holcroft, Neal; Shea, A.

In: Building and Environment, Vol. 80, 10.2014, p. 204 - 212.

Research output: Contribution to journalArticle

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