Wood Stove Chimney (flue) - wall or roof?

[wayki]

Hi good people.

I have a log burrner in a rustic spanish home - not sure what option to go for?


A) 45 degrees flue through the wall - its just a thick grey brick, no insulation, no double wall.

B) Straight up through roof - 3 layers of fencing, polysyrene, and then metal corragated rood.

(obviously I would need pipe 6" away from anything combustible)



With A how would i do it?
With B how would i do it?

Which is the easiest and cheapest option?

Thanks so much.

Can provide images tomorrow if helps.

Best wishes, Mark

 

[vinn]

You definitely need to post pics of inside the room and the burner, and the outside wall and roof.

 

[bernardgreen]

rustic spanish home

Is this is Spain, ( or Spanish style in the UK ) ?

If in Spain then Spanish regulations need to be followed.

If in the UK then HETAS ( www.hetas.co.uk/about-hetas/ ) is a source of accurate advice.

pipe 6" away from anything combustible

minimum distance required in the UK regulations is 200 mm ( 8 inches )

 

[lostinthelight]

Insulated flue can be as close as 50mm if thats what the manufacturer specifies
When I fitted mine the building inspector said single wall flue should be 450mm from combustables but have a read through BR part J which covers the subject.
https://www.planningportal.co.uk/in...ombustion_appliances_and_fuel_storage_systems

 

[bernardgreen]

From page 37 of https://www.planningportal.co.uk/in...ombustion_appliances_and_fuel_storage_systems

As you said the regulations do allow for less than 200mm but only if the flue liner manufacturer states that a separation of less than 200 mm will be safe with their product. I very much doubt that a single wall flue liner would be safe with less than 200 mm. I did quite a bit of research on this having just had a flue liner fitted and having to take into account that the cottage has a thatched roof

 

[foxhole]

Depends what type of pipe and flue , double wall insulated pipe needs only 50mm from flammable material, bare metal flue requires a distance 3 times the diameter of the flue, so 6" would require 18" clearance.

Straight up thru roof is best for efficiency and avoiding soot trap. Just had mine fitted in Uk, Spain I would guess have less regulations but you need to check there.
Cheapest is to run bare flue up until it reaches anything flammable then change to twin wall and use a flashing kit thru the roof.
Something like this
https://www.glowing-embers.co.uk/Tw...lid=CNWR5o79gNECFcEy0wodb9MP7w#TwinWallExport

 

[foxhole]

From page 37 of https://www.planningportal.co.uk/in...ombustion_appliances_and_fuel_storage_systems

View attachment 110630
As you said the regulations do allow for less than 200mm but only if the flue liner manufacturer states that a separation of less than 200 mm will be safe with their product. I very much doubt that a single wall flue liner would be safe with less than 200 mm. I did quite a bit of research on this having just had a flue liner fitted and having to take into account that the cottage has a thatched roof

He is not using a chimney, straight up thru roof or wall.

 

[lostinthelight]

Depends what type of pipe and flue , double wall insulated pipe needs only 50mm from flammable material, bare metal flue requires a distance 3 times the diameter of the flue, so 6" would require 18" clearance.


Cheapest is to run bare flue up until it reaches anything flammable then change to twin wall

Which is usually 450mm or 18" from the ceiling? If there are hight ceilings though, stove manufacturers don't recommend too much length of single skin as it reduces flue gas temperatures.
litl

 

[wayki]

Here is the stove and the wall and roof.

Some of the roof fence will be cut away.

What i want to know is whether to go 45 degrees thro wall, or straight up thro metal corregated - which is easier?

(sorry theyu;

sorry two uploaded rotated for some reason.

 

[bernardgreen]

How thick is that straw / twig layer between the "roof fence" and the corrgated iron sheets ?

How inflammable is that layer and how easy would it be to ignite it ?

It appears to be the same as a thin layer of thatch. Hence it needs to be treated as thatch when putting a flue through it.

Where no chimney exists, such as in a thatched barn, twin wall insulated rigid chimney systems are normally used. Advice must be sought from the supplier or manufacturer before fitting and the normal air gap of 50mm around these systems must be substantially increased through the thatch, which must also be properly sheathed by a purpose made shield unit. Again, only accredited competent installers should be used.

quoted from http://www.chimney-problems.co.uk/thatchedproperties.php

 

[vinn]

Thanks for the pics.
Go through the wall and once outside give the pipe a substantial offset to avoid that potentially flammable eaves soffit.
Dont attempt to go through the roof.

You have a single wall black "enamelled" pipe - double wall pipe all the way from appliance to terminal is best - but, whatever, you must leave the room with a double wall pipe going through a metal wall thimble.
Go as high as you can vertical from the burner before turning to go through the wall.

Wood burner flue pipes can get unbelievably hot so if you have children then some kind of barrier will be needed to keep them away from the appliance and its flue.
The burner must be located on concrete etc
And you will need an alarm.
Mfr's Inst's will say how far from a wall or drying firewood to locate the stove.

Sparks from the terminal will pose a fire threat to that twiggy stuff but presumably there are local methods of dealing with such issues?
What about house insurance for fire?

 

[vinn]

Post #5 shows the dangers of a little knowledge in foolish hands.

 

[wayki]

You have a single wall black "enamelled" pipe - double wall pipe all the way from appliance to terminal is best - but, whatever, you must leave the room with a double wall pipe going through a metal wall thimble.
Go as high as you can vertical from the burner before turning to go through the wall.

Thanks for this - yes, I am going to go through the wall.....ok...some Qs.

Can i do 45 degrees through the wall? Or is the cutting too difficult so I have to go 90 degrees through the wall (less draw)?

Why do i need a double walled pipe? Surely some concrete around the pipe will be fine? Concrete will get a little warm -but that's ok no?

How does one cut this hole in the wall?

Thank you so much

Mark

 

[Burnerman]

A flue pipe can easily reach 300 degrees at the stove top - for heavens sake follow Vinns advice and go twin wall all the way.
45 degree bends are best but do consider sweeping the flue.....on one I did, the outlet was at 45 deg but there was a rodding point just below that.
Twin wall is expensive but once it's done, it's done.....and the house won't burn down either
John

 

[wayki]

follow Vinns advice and go twin wall all the way.

I can't really afford twin wall flue......how about these options.....

1) Larger Terracota pipe around the flue - and fill between the pipes with fireproof mortar?
2) Larger Metal pipe around the flue " "
3) Either of the above with fibreglass insulation in the gap?