Fire in domestic kitchen

[littlespark]

Popped up to see a neighbour last night to look at, and disconnect their old cooker hood.
Something on the hob caught fire, and the hood simply sucked the flames up into the extraction duct.
Fire brigade, etc etc

My question is, has the the hood been improperly fitted?
12 year old house. Hood ducts up into the ceiling, then turns horizontal and runs about 1.3m to outside. All ducting in plastic flexiduct.

They were worried that it should have been metal.... but the hood fan blades, the fan casing, the ducting reducer, all part of the hood, are all plastic.

I’m going to replace the ducting if they source a new hood. I’m thinking solid plastic rather than flexi, as I think that might be an issue.

Also to price up heat detector as recommended by the fire brigade

 

[snowhead]

Plastic Flexi is/was very common for hoods.
My own at home is metallic, similar,

https://www.NoLinkingToThis/p/manro...lexible-ducting-hose-silver-10m-x-100mm/37075

Nowadays plastic is retardant but I doubt it was years ago.

https://www.NoLinkingToThis/p/manro...VFJzVCh2RTwYLEAQYAyABEgKq3fD_BwE&gclsrc=aw.ds

 

[James]

If it is going into the ceiling, it could well be penetrating a fire barrier.
Is there living space above?

A metal duct would be better but will not provide a fire barrier if one is required.

People are always going on about fire rated downlights, they are small holes in the plaster board.

A duct directly over a source of ignition is likely to be far more of a risk than half a dozen downlighters.

 

[littlespark]

Bedrooms of the same property above.
Yes flexi is common for hoods, but my experiences have been very short lengths through a wall behind, or solid plastic duct on top of kitchen cabinets running sideways.

I can’t see anything wrong when most of the hood itself was plastic. I’m putting it down to cooking methods.

 

[Andy78]

I don't think metal flexi duct would last more than a few minutes either with flames inside it.

 

[buzzlightyear]

ceiling, then turns horizontal and runs about 1.3m to outside. All ducting in plastic flexiduct.

looks to me a bad ill fitted extractor fan, most new builds the fan is fitted either striaght through the wall out..

 

[ruston]

Did the fire spread to the void ?

 

[Midwest]

The last few bathroom fans I fitted, I installed with an intumescent collar around the fan or extract grill.

 

[littlespark]

Did the fire spread to the void ?

I believe the fire stopped in the hood, the flexi was melted but there’s no sign of burning within the void I can see.

 

[ruston]

I believe the fire stopped in the hood, the flexi was melted but there’s no sign of burning within the void I can see.

That's good , that could of turned out really nasty if the joists had caught fire.

 

[littlespark]

And today’s discovery answers the question why flexiduct was used.

That is the heating pipes running through where the duct needs to be.

And from the inside.... cables as well.

ive managed to pull the ducting in, running under the pipe.