Treatment for rusted exposed RSJ ?

[borisbathtime]

Hi - I have an exposed RSJ supporting a first floor extension (about 30 years old). It was boxed-in but the wood had rotted around it - so I removed the wooden boxing. Once exposed the RSJ looked a bit rusted so I wire brushed it, painted it with rust eater and then used waxoil to protect it. This doesnt seem to have helped much in fact a year on it looks worse. Should I be grinding it back and using oxide paint and thinking of some sort of waterproof boxing-in again ?
Thanks for any advice. Tony

 

[freddiemercurystwin]

What a peculiar set-up, is it just protruding from that rendered wall?

 

[borisbathtime]

It’s not a wall it’s a square supporting pillar part of the original construction like the one at the back corner which isn’t offset - the front one is offset to allow a vehicle to get under if needs be.

 

[^woody^]

Yes, you want to do a proper job with some quality primer and paint, and hurry up about it.

 

[Harry Bloomfield]

Yes, you want to do a proper job with some quality primer and paint, and hurry up about it.

Then arrange something to shelter it, from the worst of the weather.

 

[Old Salt]

If you box it in I would leave some vent holes and or an inspection cover so you can keep an eye on it.

 

[Harry Bloomfield]

If you box it in I would leave some vent holes and or an inspection cover so you can keep an eye on it.

I had in mind, something to just shed the rain, but otherwise leaving the RSJ exposed.

 

[securespark]

My surveyor recommended Galvafroid paint for a similar issue, but also recommended it could be treated this way only if it was a maximum of X% corroded (sorry, I don't have the report for the correct).

 

[borisbathtime]

Thanks - Galvafroid looks good but I’m not 100% sure the beam is galvanised- I suppose sticking out and exposed in the way it is the original builder should have used galvanised but I can’t tell.

 

[Deluks]

Scraper, then wire brush the hell out of it. Wear a mask.
Liberal amounts of neutrarust 661
Red oxide primer X2
Top coat x2

You might lose a bit of section on it, so hope that it's been slightly ovedesigned.

 

[ajstoneservices]

I would hire a a needle scaler for that job.

 

[borisbathtime]

Scraper, then wire brush the hell out of it. Wear a mask.
Liberal amounts of neutrarust 661
Red oxide primer X2
Top coat x2

You might lose a bit of section on it, so hope that it's been slightly ovedesigned.

I’ve not used one before but I was thinking of maybe using an angle grinder with stripping disc to clean it up ?

 

[Deluks]

I’ve not used one before but I was thinking of maybe using an angle grinder with stripping disc to clean it up ?

The needle scaler is a good shout.

Angle grinder ok, but not with a disc, I'd use a twist knot wire wheel. You just need to tickle it.

Angle grinders can be pretty dangerous though, especially at height.

 

[borisbathtime]

Angle grinders can be pretty dangerous though, especially at height.

Very good shout mate - two handed tools up a ladder was not a great idea - I think i'm going to go with a twist knot wire cup that fits my small hammer drill -I can operate that one handed while hanging on.
Once red oxide is on and dry any recommendations for a paint to topcoat over the oxide ?

 

[JohnD]

That steel looks like it is delaminating. I have only seen that happen on poor quality steel, either very old, or the Russian stuff that Italy used to make cars out of.

It looks like it has lost structural integrity.