Leakage Diagnosis
In the event of a building failing its air permeability test, the priority becomes finding the sites of excess leakage, to enable remedial works to take place, which will hopefully reduce the recorded air leakage rate to below the required maximum. Stroma is frequently singled out for praise regarding this aspect of our service. There are three fault diagnosis techniques available to us – each using the test fans to ‘activate’ the leakage paths within the building.
Full Building Smoke Testing
This is a useful holistic procedure for identifying the general mode of air leakage within a building. By prior arrangement, Stroma will mobilise the appropriate number of specialist smoke machines required to fill the building with a benign theatrical smoke. Once filled – and with the ventilation systems sealed off – the building is then pressurised using test fans to cause the smoke-laden air to permeate out of the building via the uncontrolled air leakage paths. Conclusions can then be drawn as to routes being taken to the point of egress and the remedial measures required. Stroma will provide photos and video footage of the procedure, although we always urge contractors to witness the procedure first hand.
Localised Smoke Testing
While this procedure is the most time-consuming and laborious, particularly on larger more complex buildings, it is nonetheless indispensable in fault finding. This is because it locates individual leakage sites where they need to be addressed – on the warm side of the insulation. Stroma Engineers are experienced in carrying out methodical localised smoke testing using hand-held smoke-puffers to highlight the presence of leakage paths. The offending details are then photographed and noted for subsequent reporting purposes.
Infra Red Thermography
Stroma can carry out thermographic surveys of buildings as well as thermal imaging of electrical/ mechanical components and assemblies. Reports are provided that are detailed but easy to understand, thanks not least to the use of ‘paired’ infra-red and photographic images.
Thermography is a diagnostic technique that is increasingly being employed to survey and record the thermal properties of buildings.
It involves the use of sophisticated thermal imaging cameras that are able to reliably determine surface temperatures through detection of electromagnetic radiation in the infra-red spectrum. When working in accordance with recognised methodologies, such as BS EN 1378:1999, an experienced Thermographer can offer interpretations of the features presented in thermographic images.. Consequently, it is a powerful tool in diagnosing typical weaknesses in the thermal integrity of a building.
Thermography Benefits
A non-destructive/invasive technique.
Quick and cost-effective.
Reports, images and interpretations are easy to understand by non-trained persons.
Reduces subjectivity in assessment.
Can be used to predict where future problems such as internal mould growth may occur.
Can also be used to detect possible defects in mechanical and electrical plant and components.
Thermography Limitations
Cannot be used to quantify thermal loss or air-leakage (i.e. not a pass/fail exercise).
Surveys are weather dependant.
Dependant on HVAC systems being operational, therefore usually can only be carried out when the building is nearing completion.
Requires clear access and a direct line-of-sight to building envelope surface. Roofs can be difficult to survey.
We can devise and deliver a complete package of services to meet your requirements efficiently and cost-effectively. For lead times and fee structures, please contact Stroma directly on 0845 621 1111 or email contracting@stroma.com and we will be happy to propose an approach for meeting your requirements.