12/05/2026
We have seen videos of rotting roofs a lot recently—but they are missing one crucial piece of information. 🛑🏠
We recently came across a video on LinkedIn showing severe damp and rot in a pitched roof following a spray foam installation. Videos like this are unfortunately common, and they are doing massive damage to the reputation of modern, highly efficient insulation.
But here is what the headline isn't telling you: Not all spray foam is the same.
When you see a rotting roof, you are almost always looking at the wrong product installed by the wrong people. In the video, a closed-cell spray foam was used. This was likely applied by an unapproved contractor completely ignoring the manufacturer's strict building science guidance.
At ScotFoam, we would never install closed-cell foam on this type of residential job.
If we are insulating a standard pitched roof, we exclusively specify open-cell spray foam. Why? Because it is fully breathable. It expands to create a seamless thermal blanket that stops freezing draughts instantly, but crucially, it allows moisture vapour to pass safely through. This keeps your timber frame healthy, dry, and rot-free.
This video is the perfect example of why you can't just hire someone to "point and spray." Before you let anyone insulate your property, you must ask them these four non-negotiable questions:
1️⃣ How long have you been trading?
2️⃣ Are you an officially approved contractor for the product?
3️⃣ Is the foam you use BBA or KIWA certified?
4️⃣ Will I receive a manufacturer-backed guarantee?
If they hesitate, close the door.
We use strict building science to specify the right material for your property, and we have the certifications to back it up. Watch Barry expand on this below! 👇🎥