Roof Replacement Feasibility

Industrial Site Roof Replacement Feasibility

OMNIA delivered a comprehensive feasibility assessment for the reroofing and asbestos management strategy at this industrial site.

Project Overview

This project involved assessing the most appropriate and compliant method for completing reroofing works across a warehouse and office buildings. The site comprises approximately 3,516 m² of corrugated asbestos-cement (ACM) roof sheeting, with partial installation of an Isothane Impervius encapsulation system that had been paused mid-project.

OMNIA were commissioned to deliver a detailed feasibility report that explored multiple technical, safety, and financial options for the completion of works, ensuring minimal disruption to the 24-hour operational facility.

Project Objectives

The key objectives of the feasibility study included:

To determine the safest and most cost-effective approach to complete reroofing works over occupied operational areas.
To assess and compare asbestos control options to ensure full regulatory compliance.
To evaluate the condition and long-term viability of the existing Isothane Impervius system.
To produce phased work plans allowing continued business operation.
To establish project costs, risk analysis, and compliance with Building Regulations and CDM 2015.

Project Execution

OMNIA’s building pathology and project management team undertook a full feasibility and site review process including site inspection, drone survey, stakeholder engagement, and risk analysis. The assessment covered three principal options for completion:

Option 1 – Full Removal and Replacement

Scope of Works:

Full removal of all ACM roofing materials under controlled conditions.
Installation of a new insulated Kingspan QuadCore roof system meeting current Building Regulations.
Replacement of all flashings, gutters, and cappings.

Key Features:

Delivers a new, warrantied roof and eliminates asbestos entirely.
Highest capital cost and longest programme due to decanting requirements and licensed asbestos handling.

Option 2 – Overlay with New Roofing System

Scope of Works:

Retention of existing ACM and Impervius layers.
Installation of a 0.7 mm plastisol-coated profiled steel roof over cladding with integrated insulation and Plygene gutter lining.

Key Features:

Moderate cost solution.
Shorter programme with minimal downtime.
Requires structural load verification and Planning/Building Control approval.
ACM remains on site under ongoing management duty.

Option 3 – Continue with Isothane Impervius System

Scope of Works:

Completion of the previously started Impervius encapsulation coating to the remaining roof areas.
Minor repairs to exposed sections and re-coating for water integrity.

Key Features:

Lowest initial cost.
High uncertainty regarding warranty, long-term performance, and manufacturer approval.
Recommended only as a temporary measure.

Surveys and Technical Input

Prior to any works proceeding, OMNIA recommended:

A structural engineering survey to confirm load-bearing capacity for any overlay system.
A drainage assessment to verify that modified roof levels and falls would not compromise performance.
Updated asbestos R&D survey and reassurance air testing during all work phases.

Statutory & Regulatory Compliance

Planning Permission required for any alteration to roof form or material.
Building Control Approval mandatory for all permanent works to confirm compliance with insulation, fire, and structural standards.
CDM 2015 Regulations applicable - appointment of Principal Designer and Principal Contractor essential.
All works to be performed by UKATA-trained operatives under approved asbestos procedures.

Phased Delivery Strategy

Given the sites continuous operations, OMNIA structured a six-phase approach:

Site Setup: Establish welfare, compound, decontamination, and traffic management.
Office Roof: Commence works in low-impact area with temporary staff relocation.

3-5. Warehouse Roof: Sequential completion of roof sections to maintain safe operation zones.
Completion & Handover: Snagging, testing, and final certification.

This sequencing allows operational continuity but extends total duration compared to single-phase execution.

Challenges & Solutions

Asbestos Risk: Ensuring strict fibre control under live operational conditions through air monitoring and phased isolation.
Operational Continuity: Maintaining 24-hour warehouse use while executing high-risk works through controlled zoning and scheduling.
System Compatibility: Verifying overlay and Impervius materials for compliance and durability.
Regulatory Coordination: Managing Planning, Building Control, and CDM obligations concurrently.

Recommendations

Following full analysis of cost, programme, safety, and operational factors:

OMNIA recommended proceeding with Option 2 – Overlay with New Roofing System as the most balanced long-term solution.

This approach offers:

Compliance with Building Regulations.
Reduced asbestos disturbance risk.
Lower overall cost than full removal.
Minimal disruption to ongoing operations.

Option 1 remains the ideal long-term solution for complete asbestos removal if redevelopment or future regulation changes demand it. Option 3 should only be considered temporary pending full validation.

Client Outcome

The client received a detailed, actionable feasibility study outlining safe and compliant routes for their roof replacement project. OMNIA’s methodical approach provided clear cost comparisons, regulatory guidance, and a phased strategy ensuring uninterrupted business continuity.

This project demonstrates OMNIA’s capability in delivering complex industrial refurbishment assessments, balancing technical safety, operational needs, and cost efficiency to support strategic client decisions.