Fireplace conversion: Wood burning stove with Oak mantle...

[craig1664]

Hello,

I'm halfway through a project that I started back in December. I opened up the fireplace in my living room and put in a wood burning stove. Bit of a job but the stove is in and working well.

My next and final bit to complete is fixing an oak beam for a mantle. I've bought a 7"x7"x52" green Oak beam to do the job. My dilemna is how to fix it to the wall. I don't want to go down the path of building two pillar to support it and would much rather support it with anchor bolts.
I have done a bit a research and it appears that three 20mm threaded bar anchors fixed into the chimney breast with anchor resin and then anchored into the beam will do the job???
My only concern is that the beam is a lot heavier than I thought it would be.
Is this adequate????

 

[JohnD]

green oak is going to move a lot as it dries out. You might to well to fix brackets to the wall, and stand the board on the brackets, lightly screwed. The screws will probably oull out as it twists and warps.

When it has finished moving you can fix it more firmly.

See the Chesterfield steeple for an example.

 

[big-all]

heeelllooo and welcome craig 1664

nice job bet your rightly proud

did you do it via a hetas engineer or have your work certified by building control ??

 

[craig1664]

Thanks JohnD any recommendations on a particular type of bracket?
Big all the stove was installed by a hetas engineer. Although I will try most things I tend to let the pro's do the important bits.

 

[big-all]

Big all the stove was installed by a hetas engineer. Although I will try most things I tend to let the pro's do the important bits.

excellent craig
people often ignore the the regs or don.t even know about them hence my question

stainless 8mm bar 10" long
drill a 10mm hole in the back every foot or so 5.5" deep
drill corresponding holes in the wall at a slight down hill angle off around 1 degree 5.5" deep

fill the holes with no nails or foaming pu glue[like gorrila ]
check for level and leaning and prop up as required

edit do notdrill holes in the chimny breast unless you know as a fact you will not puncture the flue or lining

 

[craig1664]

Thanks again Big-all. Do you think 8mm bar is strong enough??? The oak beam is heavy.....and I've got to be honest, I was thinking 18 -20mm bar would be about right?

 

[craig1664]

Sorry Big-all forgot to ask. You say that you would use no nails or foaming pu glue. Is this more preferable than anchor resin due to potential movement or just a cheaper way to anchor the bars??

 

[big-all]

if you place them near the top then most off the force is in shear
mind you you could go for every 8 to 10" if your worried lol
yes you can go for larger diamater and resin if it makes you happier
but as the oak is a dead load there's little chance off a problem

 

[JohnD]

but as it is green, it is going to twist a lot as it dries out, so I would go for a fixing that allows it to move for the first couple of years.

you could rest it on "L" brackets firmly fixed to the wall and lightly tacked to the beam.

have you looked at the photos of the Chesterfield steeple, made with green oak by cowboy builders?

one of the places I briefly worked

 

[thatbloke]

Green oak may not twist too much if your lucky but it might split.
Why not go for quarter sawn air dried? Its not that much more expensive and is well worth the extra.

http://www.quartersawnoak.co.uk/

Carved oak brackets underneath the mantel might be in keeping with the fireplace, you could possibly even get away with 5''x7''.

 

[big-all]

i should further add my comments where to the weight and large volume off the timber
and indeed would not suggest fixing until the oak has at least 6 months in the room off use an ideal situation would be nearer 2 years in situ
i would not be surprised to find a 2" hollow end to end or a 1/2" split in green oak

of course the movement will be further aggravated by the heat from the fire

 

[craig1664]

Thank you all at this point. I think I'm gonna go with the anchor bolts. Probably 12 - 15mm. Use resin for the anchors into the masonary. Trim the beam down to 5x7 and drill into the 5" face 4" deep with a larger drill bit.
At this juncture I am considering not using glue in these holes to allow for movement, however i will be using glue to tack the beam temporarily to the masonary.
will post a few photos when in place. We just considering what to treat the oak with?? We would like a worn brown look. Any ideas?