How to protect Glulam beam in chimney

[eros_poli]

Hey

 

We’ve got a small Glulam sitting on a padstone in our chimney, as a ridge beam. 
 

I’m wondering how best to protect the end of the beam that sits within the brick work, as it’s a chimney with all the associated things: sooty/tarry bricks, condensation etc. 

 

Any advice? Treatments? Oils? Wraps?

 

Thanks

[JohnMo]

Not sure how a wooden structural element can be allowed to be in a chimney? Are you not asking for a fire, or the end of the glulam to burn away?

 

You may need to provide a drawing as what you are saying doesn't sound right.

[nod]

It’s fine sat on the inner leaf of the chimney Ie with a cavity and block between the heat from the chimney 
 

[eros_poli]

Unused chimney, approved engineers design and approved by building control. 
 

any suggestions for timber protection in this environment welcome 

[nod]

5 minutes ago, eros_poli said:

Unused chimney, approved engineers design and approved by building control. 
 

any suggestions for timber protection in this environment welcome 

If they have passed it As is 

It doesn’t need protecting 

[Redbeard]

5 hours ago, eros_poli said:

I’m wondering how best to protect the end of the beam that sits within the brick work, as it’s a chimney with all the associated things: sooty/tarry bricks, condensation etc. 

 

Any advice? Treatments? Oils? Wraps?

 

It depends to a degree on how well-ventilated the disused flue is. It should be really well ventilated ideally, but in some circumstances the 'in' (at the bottom) will be from the inside of the house (an air-brick in the ch brst in a room), not from outside. Which is the case here? If the air feed is from outside and the discharge is via the top of the stack then I am not sure you have much to worry about re condensation. If the air feed is from inside a room then you may have something to worry about, as the 'feed' is of warm moist air, not cold drier air. The warm moist air can reasonably be expected to condense out in the upper reaches of the flue. 

 

Other protection I would argue is less necessary since  you will have a padstone below, and arguably a small lintel above. You could put in physical protection at the sides, but I would prefer, say, slate rather than (potentially sweaty) plastic. (OTOH it probably won't be sweaty if the cross-ventilating air is dry enough, as above).

[Mike]

Combustible structural materials need to be 200mm away from the inner face of a masonry chimney flue in order to meet the requirements of Building Regs Part J. You'd therefore have to ensure that it can't be used as a chimney in future to avoid those requirements - for example by permanently blocking it with that padstone & considering how to avoid the potential for elevated moisture levels within the old flue. Provided you've done that, there's no need for further protection for the beam.

[Temp]

I think a sketch is needed. As I understand it between the "fire" and the beam you have a block (or pumice liner?) and a cavity? If that's over 200mm I don't think anything is needed. The top of the cavity will be sealed. Perhaps wrap the end in DPM?