How to stop smoke entering the house

[Narmnaleg]

HELP!!! I've finally settled into my new home and last night I cooked my first charcoal BBQ (pork ribs). The ribs were great, but heaps of smoke came in the house and the smoke alarms were all going off. Obviously this situation is unsustainable and I need to find a way to solve it, so I'm appealing to our collective wisdom. The issue seems to be due to a gap just under the extension's roof. I have a metal roof that was installed for the extension and it slopes away from the original part of the dwelling, and over the end of the extension onto the deck.
There is a gap (about 200mm) between the roof and the ceiling which is currently just metal netting. This gap lets my BBQ smoke in from the deck to the ceiling-roof cavity and subsequently into the house. I need to either close the gap or find an alternative solution by installing some kind of smoke diverter/range hood. Any help or advice would be much appreciated.

[food&fish]

I recon a photo would help

[Gumb]

Yep, a photo would be good.

[Narmnaleg]

Sure thing, here are three pics:

1) Photo of the roof taken from the deck, you can see that there is also some flashing which is approx 500mm deep:



2) Photo highlighting the gap (on the outside) between the flashing and the plastic deck roof:



3) This photo shows the netting (or whatever you call that stuff) from inside the cavity between the ceiling and metal roof of the extension. The photo was taken from the manhole:

[Gumb]

Sealing the gaps under the roof sheets is easy enough. Bunnings sell a foam strip which is the same profile as the laserlite so it just slides in. The other gap is a bit harder and depends on access but maybe some heavy duty plastic either stapled or fixed to the timber with those spiked metal clips they hammer in to hold shade cloth. There's a slo that gap filling foam which expands as you spray it in but it can look messy and the gap might be a bit big.

[Narmnaleg]

Thanks Gumb, I think I can just unscrew the flashing and put it back once done so perhaps I can install the foam strip flush with the wall and the roof, but from the outside? (I have zero chance of accessing it from the cavity)
I could then close any remaining gaps with expandafoam....

[Bear]

Hard to tell, but if the extension roof sheets don't already have one, installation of a back channel with a bitumen foam strip fitted would close the little gaps created by the corregated sheets. then cement sheeting to block the larger gaps. You'll probably need another timber level with the top one to nail the sheets onto. It'll be a PITA if you don't have the skills or tools though.

[Narmnaleg]

It'll be a PITA if you don't have the skills or tools though.

Thanks Bear, unfortunately I don't have either. Do you know which trade I should call to do it? Metal roof installers?

[Gumb]

Here's the foam draft stopper from Bunnings.



it just sits on top of the batten.

[Bear]

A general builder should be able to help this.

[Gumb]

More like a handy man job. Builders quite rightly charge more per hour and it's nothing to do with structural integrity.

[Narmnaleg]

I think I'll have a look at bunnings for that foam as a starting point. Hopefully it's enough to stop the smoke getting in. I can remove the flashing so closing the gap from outside should be straight forward as long as the foam fits... I'd still be keen to hear about smoke diverters though.

[Burnt offerings]

I just use a pedestal fan to keep blowing the smoke out of my pergola.

Might work for you.

[Narmnaleg]

I just use a pedestal fan to keep blow the smoke out of my pergola.

Might work for you.

That's a good idea also. Thanks Burnt.

[Narmnaleg]

I think I have a plan of action for this weekend:
Use this foam for the laserlite gap near the roof: https://www.masters.com.au/product/9000 ... rips-900mm
Then use this aluminium tape to cover the gap in the netting: https://www.masters.com.au/product/9000 ... 220mm-x-5m
Any small gaps that are left could be dealt with expanda foam.

Thoughts?