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Misconstruing that buried pipelines do not lead to catastrophic failures while other constructed structures are deemed susceptible to failure is not uncommon. This paper presents some innovative research methodology underpinned by case studies to endorse that design and construction of buried pipelines need amenable interdisciplinary communications between materials, hydraulic, geotechnical, structural, and construction engineers. An initial outline sets the scene for the gravity of consequences from buried pipeline failures. The paper proceeds to expound related reasons and intelligent infrastructure solutions arising from forensic investigations of such failures. The inevitable influences from material aging and geo-environmental effects on a variety of pipeline projects are then presented. It is more the reason that smart contractors need to vigilantly adhere to contract specifications of a project, appreciating the significance of the variability in the foundation soil, geo-environmental, and construction hazards. Further attempts were made to distinguish between pipeline failures consequential to factors over and above soil–pipeline interaction influenced by soil loads surrounding the pipe. Shortsighted, hasty decisions in construction practice to economize on time and construction costs will lean toward collapse, resulting in unforeseen ancillary costs. The author shares his expert evidence experience and innovative, sustainable research solutions covering different failure scenarios. The paper further presents unorthodox geotechnical and material investigations and smart engineering solutions carried out by his numerous postgraduate researchers and others within a pipeline research group in the UK. The cases cited will hopefully enthuse the quest of interested readers to develop further through the references cited, the need for lateral and logical thinking “outside the box” for forensic geotechnics and pipeline engineering.

Moisture and heat management properties of Hemp and Stone Wool insulations were studied by mounting them between a hot and a cold climate chamber. Both insulations were exposed to identical hygrothermal boundary conditions. Quasi steady state and dynamic tests were carried out at a range of relative humidity exposures. The likelihood of interstitial condensation was assessed and equivalent thermal conductivity values of the insulations were determined. The adsorption-desorption isotherms of the insulations were also determined in a dynamic vapour sorption (DVS) instrument. It was observed that the likelihood of condensation was higher in Stone Wool insulation than in Hemp insulation. Hemp insulation performed better in managing moisture due to its high hygric inertia and water absorption capacity. It was observed that the equivalent thermal conductivity of Stone Wool insulation was dependent on enthalpy flow and phase change of moisture. The equivalent thermal conductivity of Hemp insulation was close to its declared thermal conductivity in dynamic conditions when high relative humidity exposures were transient. In quasi steady state boundary conditions, when the insulation was allowed to reach the equilibrium moisture content at ranges of relative humidity, there was a moisture dependent increase of thermal conductivity in Hemp insulation.

An in situ experiment on a full-scale timber frame test building was carried out to study the hygrothermal performance of wood-hemp composite insulation in timber frame wall panels with and without a vapour barrier. The heat transfer properties and the likelihood of mould growth and condensation in the panels were compared. Step changes in the internal relative humidity were performed to explore the effects of high, normal and low internal moisture loads on the wall panels. No significant difference in the average equivalent thermal transmittance (U-values) between the panels with and without a vapour barrier was observed. The average equivalent U-values of the panels were close to the U-values calculated from the manufacturers’ declared thermal conductivity values of the insulation. The likelihood of condensation was higher at the interface of the wood-hemp insulation and the oriented strand board (OSB) in the panel without a vapour barrier. In terms of the parametric assessment of the mould germination potential, the relative humidity, the temperature and the exposure conditions in the insulation-OSB interfaces of the panel without a vapour barrier were found to be more favourable to the germination of mould spores. Nonetheless, when the insulations were dismantled, no mould was visually detected.

Purpose – The purpose of this paper is to describe and discuss initial work to assess the moisture buffering performance of selected bio-insulations in lofts that suffer from excessive moisture following refurbishment. Design/methodology/approach – These conditions were then reproduced in a physical lab-based experiment such that the comparative performance of the bio-insulations and stone wool could be measured. Findings – It was found that the bio-insulations could remove over 60 per cent of the moisture in the loft air, and therefore reduce the risk of condensation and its severity. Research limitations/implications – The initial work reported here is indicative of the buffering potential of bio-insulations but further work is required to better quantify this performance. There is a need to further examine lofts with moisture problems and to produce reliable testing methods and protocols to be used when retrofitting loft insulation. Practical implications – Installers and specifiers of loft insulation should ensure that insulation is installed correctly, as with the drive to increase loft insulation levels the risks of damaging the building fabric through condensation are increasing. Social implications – Excessive moisture can damage the building fabric and create health problems. Using insulations that perform well across a range of performance criteria tend to favour bio-insulations, which have a far less harmful impact on the environment than do typical fossil-fuel based insulations. Originality/value – The paper presents preliminary findings that support arguments for specifying bio-insulations.

An in situ experiment in a full scale timber frame test building was carried out to compare the hygrothermal performance of Hemp and Stone Wool insulations of identical thermal conductivity. Hemp and Stone Wool insulations were installed in timber frame wall panels without vapour barrier. The comparison was made in terms of heat transfer properties, likelihood of mould growth and condensation. Step changes in internal relative humidity were performed to explore the effect of high and normal internal moisture load on the wall panels. No significant difference between the average equivalent thermal transmittance (U-values) of the panels incorporating Hemp and Stone Wool insulations was observed. The average equivalent U-values of the panels were closer to the calculated U-values of the panels based on the manufacturers’ declared thermal conductivity of Hemp and Stone Wool insulations. It was observed that the placement of heat flux sensor along the depth of the insulation had significant influence on the measured equivalent U-value of the panels during high internal moisture load. The frequency and likelihood of condensation was higher in the interface of Stone Wool and Oriented Strand Board (OSB). In terms of the parametric assessment of mould germination potential, relative humidity, temperature and exposure conditions in the insulation-OSB interfaces were found to be favourable to germination of mould spore. However, when the insulations were dismantled, no mould was visually detected.

The paper presents the results of a laboratory investigation on the hygric properties of five hemp insulation materials commercially available in the UK. The hemp fibre content varies between 30% and 95% in the total fibre content of the insulation materials examined. The adsorption–desorption isotherm, moisture buffer value, vapour diffusion resistance factor and water absorption coefficient were determined for the insulation materials investigated. The results showed that the hygric properties of the hemp insulation materials could vary widely depending on the constituents and fibrous structure. The considerable differences noted in the hygric properties of the insulation materials examined could potentially influence their hygrothermal performance as part of a building thermal envelope.