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I'm opening up a wall at home and an engineer has chosen me a suitable sized steel beam to do the job. I'm wanting to clad it in plasterboard to give it some integrity should there be a fire and my question is ideally should it achieve 30 or 60minutes of resistance and what would be the best way to go about it? Thanks in advance for any replies.
Use a double layer
of 12.5mm board or a single layer of 12.5mm fire check board for 30 mins protection
30minutes if two storeys, 60 if 3 or above
If space or appearance is an issue, perhaps try intumescent paint? This will give you the required fire protection for a couple of coats of paint. Not cheap though!
This is what we use on steelwork, as said it isnt cheap but then are your lives?
http://www.nullifire.com/
Needs applied as thick as possible. there is a test for thickness but just go over the top on application
Appreciate the advice folks!
Needs applied as thick as possible
No it needs to be applied at the correct thickness. While I'm not familiar with that particular product in general the people who formulated it did so that it met suitable characteristics at the given thickness. Often applying too much puts the coating under stress so it will crack before it has a chance to form a protective char when heat is applied. It may even fail prematurely in service.
Paint wise you'll probably be best using a single pack waterbased product for a cellulosic fire as that will be easier for a non specialist applicator to handle.
Consult your engineer for proper advice, there are plenty of BS standards for this type of thing that prescribe what needs to be done.
Here is some basic information
http://www.international-pc.com/products/fire-protection/fire-protection-technical-information.aspx
There are plenty of other options for passive fire protection on steel. Cladding is the obvious alternative, especially if you are going to encase it anyway.
I work for Akzonobel, all views my own, I don't work in the fire protection bit anymore.
2 layers of plasterboard with staggered joints is all you need.
@ jonba, not what the guy checking the nullifire told as as he was checking our work at spillers factory. There is a limit on the least amount but thats it
Ive put loads of the stuff on in the past.
Plasterboard to satisfy BC. Forget everything else. A big beam mid GF/FF is not going to get hot enough to give way, and if it gets hot enough to buckle your house will be a knocker downer anyway.
This kind of serious fire resistance is for buildings where any loss of structural integrity in any one member is catastophic to the integrity of the structure.
Seanodav your Nullifire man is giving out very very bad advice. I formulate these products and putting too much on (even 0.5mm) will greatly increase the available material in a fire situation and will make the char expand too much, become too heavier and most probably lead to char slumping or even detachment. This will occur early in a test as well so will leave the steel exposed within 30 minutes.
Glacier i would recommend plasterboard as your best option- certainly cheapest. if you go for a intumescent make sure you use the correct primer as that will have significant effects.
Ohh dear lots of unsafe steel kicking about then in that case, however it was tested and signed off...
Edit: in the case of over application how is it reduced then? reckon that could get tricky
As above, double plasterboard with staggered joints
One layer of fireboard or two layers of plasterboard is standard for domestic - >30 minute fire protection.
We went with fireboard because our beam sits on pillars which are the same width as the beam so everything will be flush once it's done.
What does the wall support?