A key area of contention within the jointly authored PCA protocol is the interpretation of spray foam applied directly to primary roof coverings, particularly HR membranes.

In the assumptions section, the protocol includes the following bullet point :

Where foams have been applied directly to the primary roof coverings as a means of improving thermal performance or to stabilise failing roof coverings or have been applied directly to underlays that are considered to be of high vapour resistance, an assumption may be made that such installations are high risk.

Our experience is that this bullet point is frequently being used as a blanket justification for (incorrectly) recommending removal of all such installations. This reading is not consistent with the instruction that immediately follows (Note: Assumptions should only be made when there is no written or observed information to call them into doubt.), nor with the overall framework of the protocol.

The note makes clear that where an installation is accompanied by full supporting documentation, or where inspection shows no defects, the correct approach is to follow the process flow chart in the appendix. That flow chart classifies such cases as low risk, meaning removal is not necessary, nor should be advised.

The protocol is therefore structured around a risk-based assessment, balancing both the presence of documentary evidence and the observed condition of the installation. The purpose is not to assume inherent failure risk simply because spray foam has been applied to an HR membrane, but to ensure that any assessment is evidence-led and proportionate.

In practice, however, we are seeing a trend of surveyors bypassing the process flow chart, applying the bullet point in isolation and defaulting to recommendations for removal regardless of documentation or observed performance. This is a misapplication of the protocol and undermines its intent.

The protocol should be interpreted holistically:

• Documented installations with no visible defects = low risk (removal not recommended).
• Absence of paperwork or evidence of issues = elevated risk (further action may be warranted).

Consistency in applying this framework is essential if the protocol is to fulfil its purpose of providing a robust, evidence-based methodology for evaluating spray foam installations.

Back to News