I have an inglenook fireplace with no hood. However i have been given one that was previously on a gas fire. Does anyone know if this will be suitable for an open fire, and if not, what does the right hood need?

justajennyus wrote:
I have an inglenook fireplace with no hood. However i have been given
one that was previously on a gas fire. Does anyone know if this will be
suitable for an open fire, and if not, what does the right hood need?




Ah. Now I can help you there..

When faced with two inglenooks that smoked very very badly, I did some
net research..and eventually found just ONE site that had the
information I needed.


What you need to know is that at the hood exit - provided its smoothly
curved anyway, you should have no more than 5 to 7 times the area of the
cross section of the hood aperture, available as the area around the
hood - between its circumference and the level at which the fire is.

Now in a GOOD inglenook, with a properly corbelled flue entry and a
reasonably low aperture, you don't need as hood at all.

The first thing to do is to measure the flue area where it exits the
ingle nook. As I said, if its properly corbelled this will equal the
floor area of the inglenook itself - the fact that it narrows later on
is not a problems as long as you have about a one foot square flue up
the stack. And the wider part of the flue extends well upwards. The
inlaws have such and the stack does not narrow into its final size until
the top of the floor above.

Now you have to measure the aperture of the inglenook - essentially its
frontal area. If this is less than 5 times the floor area you should
have a good setup that needs no hood.

In my case however I simply had a one foot square flue in a flat topped
inglenook and no 'smoke chamnber' at all. I curse the builder who said
it would work.

In essence I built smoke hoods to reduce the aperture and form the smoke
chamber.

When doing this INSIDE the inglenook you have to forget about the walls
of the nook and leave them out completely. In may case with exactly one
square foot of exit, I had to limit myself to an aperture - the area
between the base of the hood and the grate (not the inglenook floor by
the way - just where combustion takes place - we have raised grates on
dogs)to no more than 7 square feet at most. In our case this meant a
hood that was slightly larger than the grate and low enough over it to
reduce the air gap and get enough airflow speed to suck any stray smoke
into it. Its not totally perfect - the room always smells slightly of
wood smoke in winter - but we rather like that anyway.

Our hood was about 3ft x 2ft so really it had to be no more than a foot
above the grate. ( 3ft wide plus two 2ft sides is 7ft, times one foot is
7 square feet). In fact its a bit higher than that, and isn't perfect.
We could prop the grate up on blocks, but round tuits are in short supply.

What is useful, is to mock up the hood itself using stiff cardboard and
masking tape, and build a small fire out of whatever..you DON NOT want a
hot fire as its both dangerous and also will have a higher flue
velocity. A nasty smokey 'i've just been lit with wet wood' one is what
you want. You will see the way the air gets drawn in and the smoke
retained.

In our case the biggest problem is stuff that burns near the edges of
the grate or rolls out of it smouldering. There isn't enough draught to
cope with that.

Once you have established the hood size, you have the fun of getting one
made. Try a blacksmith.

Good luck.