Intumescent strips - Paint

[Marko01]

Afternoon, wonder if you could help?

I was recently inspected by Fire officer and he found two intumescent strips which had paint on them from the painted door frame which he said compromised the effectiveness of the door frame.

I am just curious as to whether those, with better knowledge than I, would agree that the paint negatively affects the integrity of the intumescent strip.

Thanks

Mark

[billinom8s]

i would guess it depends on what the paint is made from, does it have a low flash point?

how much paint is on the strips?

if it was splashed then he sounds like he is being picky, if it's a sealing brush stroke that will stop the strip expanding and blocking the gaps then he has a good point.

[Messy]

99% certainly an over enthusiastic Inspecting Officer

Most strips can be overprinted, but not cold smoke seals as they need to flex

What are these doors protecting?

[8VUyau7]

As previously mentioned it depends on the use of the fire door, and whether cold smoke seals are fitted.

If it were just intumescent strips (without cold smoke seals) then the LABC suggest five coats of paint is acceptable.

https://www.labcwarranty.co.uk/blog/tech-update-painting-over-intumescent-strips/

If there is cold smoke seals, then they need replacing (probably)

[witsd]

Last I checked (about 4 years ago) the British Standard said that 'up to five layers of paint' was acceptable.

How you are meant to determine the number of layers, or account for some layers being thicker than others, I have no idea.

Ultimately, the cost of replacing an intumescent strip is pretty low, so if in doubt, it's not a bad recommendation to make.

[Messy]

I havent seen that ridiculous statement in the British Standard.

How on earth do you measure a layer of paint?

To be honest , I wouldn't be to bothered about paint, unless it's fire door protecting a single staircase sleeping risk, or a L3 system in a hotel that uses heat detection in bedrooms rather than smoke detection.