RSJ's not painted

[nervous123]

So..after a year of worrying about them, I've had the RSJ's in my extension exposed for an engineer to come and inspect.

I understand they should have been painted (a) against rust and (b) against fire. However, it appears they have not been painted at all (predictably).

How important is this? Painting them complete will prove very disruptive (basically remove entire kitchen p/b ceiling, insulation, lights etc) - we have exposed them from the bedroom above so only one side of each steel is visible - any point in painting only one side of each?

Many thanks

 

[freddiemercurystwin]

Building Inspectors usually accept them if they are clad in plasterboard althugh strictly speaking it probably ought to be fireboard depending on the beam size. If you're getting regularisation check wth your inspector.

they don't need to be painted for rust protection.

 

[nervous123]

I'm not getting regularisation. I just want to know best practice, in the circumstances

The bizarre thing is that i have the Cert of Completion from LABC, despite the Chief Surveyor having admitted to me that (having not received calcs from builders despite such requests) BC assumed no steels were being used and thus did not inspect any steels (in an open plan kitchen with upper bedroom clearly visible above).

We have exposed the steels for a structural engineer to visit, measure and calculate suitability (for peace of mind)

 

[Static]

Get the engineer to also comment on fire/corrosion protection..

 

[jeds]

Are these the same beams in the other post. If so they look like they're painted standard grey? Unless my eyes - or the photo deceive me.

 

[fmck]

My loft conversion on the project forum had a steel beam that I didnt bother painting. It did need fireboard protection though for building warrant.
I dont see the point in painting unless its the intumescent stuff that I gather is pretty expensive compared to a sheet of FP platerboard.
It does seem odd to me that I have to protect a steel beam but the entire loft/roof is made of wood is unprotected. Who thought that one up?

 

[freddiemercurystwin]

Because the steel beam is supporting everything else, its about ensuring the house does not collapse immediately to give the fire brigade enough time to do a search/extinguish the fire. Some rafters dropping is OK, a steel beam fails and it brings the whole roof down.

 

[hotrod]

It does seem odd to me that I have to protect a steel beam but the entire loft/roof is made of wood is unprotected. Who thought that one up?

I asked this question to a lecturer at University many moons ago. His reply followed the lines that, "Structural timber performs better than steel in a fire in that unprotected steel will fail first as the heat affects its performance. The outer skin of large section structural timber will char in a fire but it will still retain its strength for a considerable time at high temperatures." That was the jist of the conversation when I challenged him and said "but the timber will just burn in a fire".