Loft Conversion Floor Steel Beams - Paint?

[paulrockliffe]

As I understand it, because I'm achieving 30 mins fire protection via the existing ceiling rather than any structure reliant on the new steel beams for their integrity I don't need intumescent paint.

Having just carried 450kg of unpainted steel into the loft this morning, I'm wondering whether it should be painted to protect against corrosion or for any other reason?

It's been drilled and sat outside so has some surface rust, but presumably once it's dried off and fitted it's not going to sit there slowly rusting in the warm dry loft, so would be fine as it is.

Does that sound OK, or should I get some paint on it?

Cheers

 

[Ian H]

I’d take it back downstairs and paint it

On ours the drawings said 2 coats of red oxide type stuff. They came with a bit of surface rust so we wire brushed them before painting.

 

[paulrockliffe]

They'll dry quicker outside, I'll get the lads back round in the morning and get them moved

My engineer says they're fine in general but wants to check there's no risk of condensation on the ends where they sit in the external walls outside the insulation envelope. But I suspect the answer will be that I need to take the insulation round them rather than paint them if there's a risk of condensation.

Might just get some paint and paint them anyway just in case, but would be handy to know the answer.

 

[tony1851]

Personally I wouldn't bother humping them downstairs again just to paint them. They're not going to corrode in the heated envelope, and if you're concerned about condensation where they sit in the external wall, the rate of corrosion will be very slow. There is only shear stress at the bearing, which is low, and most beams can afford to loose a lot of metal before strength at that point becomes compromised. I'd start to worry after about 200 years - seriously!

 

[paulrockliffe]

Sorry, I thought it was obvious we were both joking. Not sure I could get them down safely again without getting some lifting kit in anyway, gravity would want to get involved and speed things up!

That's a good point about the failure mechanism. Given that I suppose the only real risk is that I get the floor in then Building Control insist it's painted. I might paint them just to cover that risk given I've run out of quiet jobs I can do in the evenings while the kids are asleep, so it won't actually delay me.

But good to know it's nothing to worry about.

Cheers

 

[Notch7]

Sorry, I thought it was obvious we were both joking. Not sure I could get them down safely again without getting some lifting kit in anyway, gravity would want to get involved and speed things up!

That's a good point about the failure mechanism. Given that I suppose the only real risk is that I get the floor in then Building Control insist it's painted. I might paint them just to cover that risk given I've run out of quiet jobs I can do in the evenings while the kids are asleep, so it won't actually delay me.

But good to know it's nothing to worry about.

Cheers

Ian was joking!

if you want to paint it get a tin of red oxide primer.

 

[Leofric]

Just paint it with red oxide.

 

[Nakajo]

Just painted mine with white nullifire- looks amazing