Double brick firewall ?

[quoll]

After a bit of advice.

Got a 2br and 3br house under the same roof, looking at community titling them, surveyor has said everything looks good but will have to remove door from double brick wall and make sure it's up to firewall standards.

Had a chat with building designer and he said double brick wall will give 120 minutes fire rating so will be fine, just make sure it goes up through roof.

How do I turn this standard double brick wall into a firewall?

I've removed the door frame and now just have a hole in the wall. It seems like I just have to get the wall bricked up, remove the roof sheets (flat roof ), bring the double brick wall up through the roof, the chimney comes out by 4 or 5 bricks anyway, ( will have to brick that up as well ). Then just put new flashing around roof/wall. But what happens with the eves?

Had a look at a few different groups of units and duplexs some have the joining walls coming out the roof and some don't.

Seems reasonably straight forward, I need a double brick wall with nothing run through it, coming out the roof. The only I'm not sure about is what to do with the eves.

Any advice?

cheers
Graeme

 

[Sailesh Channan]

Double brick should provide sufficient fire rating. There are also other other products in the market by CSR, etc that provide other solutions in plaster boards.

Where he firewall meets the roof line you will need to ensure that it is firmly packed with rockwool.

The eaves will need to be blocked with cement sheeting and packed with rockwool.

 

[quoll]

Thanks Sailesh,

Had a look at the CSR products but in general they only give 60 minutes fire rating. The bricks are already there I just have to get them into the old door opening. I'll have to go and buy some rockwool insulation. Thanks for the tip.

Cheers
Graeme

 

[gecho1]

I've removed the door frame and now just have a hole in the wall. It seems like I just have to get the wall bricked up, remove the roof sheets (flat roof ), bring the double brick wall up through the roof, the chimney comes out by 4 or 5 bricks anyway, ( will have to brick that up as well ). Then just put new flashing around roof/wall. But what happens with the eves?

Graeme,
Double check this as i don't think you need to bring the wall (Through the roof)
Usually these walls go upto the underside of the roof.

As for the CSR products, if they only give you 60min rating, then double them up. This will give you the 120min required. We do the same thing with firecheck gyprock, often having to install 2 or even 3 layers to obtain the required rating.

good luck with it all

Adrien Mamet

www.mametconstructions.com.au

 

[csc]

re wall going to the roof...my two cents worth..i think what you need to look at it the type of roof that is there first up and go from there.........maybe difficult to build a "proper" firewall right up to the roof structure if the roof itself is not a basic style..

as gecho said the underside of the roof is the go with my local council on most occasions.....i can see your reasoning however...

id have a chat to a builder and the local council to settle your mind straight up....

good luck, nice little project

 

[Nathan]

Didi one myself.

Used Hebel sono blocks.

600 x 200 x 200 its rated for noise and sound and you dont need to lay ney foundations under the slab like normal wall easy to lay and you can cut with a hack saw.

 

[handyandy]

When filling in the door ways you will need to tooth in the bricks.

We have done a number of fill ins and the tooting has varied but each time the bricklayer recommended toothing in. On one we toothed two sections top and bottom so total of 4 bricks. on another we toothed the whole lot both sides.

As per other posters no need to come out of the roof just to the underside of the sheeting with rockwool filling the minimal gap.

On one job we had to build a full brick wall from foundations to the underside of the roof. Pic of the wall coming up, note the rafters all cut.

The engineer reckoned that we didn't have to do anything to the eaves as is considered outside of the house. We did stick the left over rockwool in there just for the hell of it.

Cheers

 

[Nathan]

Nice pic H/A

Mine i usd fire proof expandafoam and sprayed it... Was signed off no dramas... however dont reccomend it.

 

[quoll]

Thanks for all the feedback.

I'll have to check out about the roof, if the wall doesn't need to go through it that will be a lot easier. Packing out the gaps with rockwool sounds good.

I was assuming the whole gap would need to be toothed, if we can get away with only doing the top and bottom that will save a lot of time.

I'll take some pics as we go.

It's a flat (very gentle slope) tin roof, no ceiling space just tin, insulation, rafters, ceiling. A few electricity cables and a bit of copper pipe.

Cheers
Graeme

 

[handyandy]

I was assuming the whole gap would need to be toothed, if we can get away with only doing the top and bottom that will save a lot of time.

Cheers
Graeme

Sorry by top and bottom I meant a 1/3 of the way down and up. So equal distance.

Cheers

 

[Sailesh Channan]

Your brick work will need to follow the contour of the roof. This means you cannot tooth the bricks. You will need to cut the bricks at the same angle as the roof...you can use hebel for ease of cutting.

The rock wool is there to seal the small gap that remains. You are only allowed to fill a gap of 80mm with rock wool.