Roof Defect Guidance For Professional Specifiers
Technical analysis of common indsutrial roofing defects produced by Liquail’s own specialist roofing surveyors & coating inspectors.
Impartial, technical guidance on identifying, diagnosing and treating the most common defects found on industrial metal & asbestos cement roof systems and gutters.
Each topic reflects Liquasil’s surveying heritage and hands-on experience with dilapidations, roof inspections, and roof refurbishment specifications.
Help For Specifiers
Where appropriate, each of our roof defect pages contains a specification paragraph that can be copied and pasted directly into your own tender documents.
If you think you might need a custom-made specification, our team will be happy to review your survey images and create a site-specific document for your use. There is no charge for this service as we want to help you ensure that your roof coating project is successful.
This guidance is structured to support the inspection, diagnosis, and specification of remedial works for industrial metal roofs.
Identify the Defect
Metal Roof Defects Guidance
Clear explanations of common defects affecting industrial metal roofs, including how they develop, how to identify them, and the risks if left untreated.
Industrial Roof Inspection Checklist For Surveyors
Everything the professional building surveyor needs to inspect industrial metal roofs and create better reports and specifications.
Underside Corrosion to Metal Roof Sheets
Guidance on concealed corrosion mechanisms beneath overlapping steel roof sheets and their implications for refurbishment.
Treating Mid-Lap Corrosion
Mid-lap corrosion is often treated in a blanket fashion that can create a latent defect and cause greater damage to a metal roof.
Treating End-Lap Corrosion
Guidance on treating end-lap corrosion on pitched metal roofs. How to identify, prepare and treat this common defect.
Metal Roof Fixings
Identifying and understanding defects surrounding the fixings on pitched metal roofs. A guide for dilapidations, condition and acquisition surveyors.
Industrial Gutters
Discusses the advantages of liquid gutter liner systems and how to properly install them to ensure a permanent and long-term solution for industrial gutters.
Silicone v Hybrid or STP Coatings
Silicone coatings provide a reliable and robust way of refurbishing pitched metal roofs. Hybrid STP polymer coatings are also available, but which is best?
Specify the Right Approach
Best Practice Guidance
Practical guidance for inspecting, assessing, and specifying roof works, helping ensure that remedial strategies are appropriate, proportionate, and technically sound.
How To Conduct Metal Roof Inspections
Guidance on how to conduct formal & professional metal roof inspections. A guide for surveyors on process and reporting strategy.
Best Practice for Lining Industrial Gutters
A surveyor’s guide to inspection and specification of industrial gutter lining systems. Understand the issues concerning industrial guttering and specify the right solution every time.
Best Practice for Measuring an Industrial Roof for Coating Works
A technical guide to accurately measuring steel profiled roofs prior to coating
Best Practice For Specifying Metal Roof Coatings
Ensure the correct selection and specification for a roof coating, based on the conditions of the roof.
See Real World Outcomes
Roof Defect Case Studies
Real-world examples of roof defects identified during inspection, including conditions that may not be apparent from routine top-side surveys.
Severe Underside Corrosion at Mid-Lap Joints
- Loss of lower sheet across purlin line
- No internal leakage despite structural deterioration
- Evidence of concealed corrosion within lap joints