gas fire regs gather hood/closure plate?

[Reg Man]

Tapered flue gather for connection at bottom of chimney.

 

[lame plumber]

"connection of the new flue to the existing chimney liners" is about sealing the flue, so that the dangerous gases don't blow back down into the room. This is the purpose of a closure plate. The condition of the flue liner has nothing to do with how it is sealed to the new flue/ closure plate setup. I will post photo once it's done to clear it all up finally.

closure plate is found behind a gas fire to seal it to the vertical wall. A register plate is used to seal a fireplace horizontally to prevent dirt and debris falling into the hearth. You can then run a flue to the register plate and up into the chimmney to remove the pocs use the original flue if safe to do so or then connect it to a flue liner. please ensure you know what you are talking about or you may confuse other people reading this.

 

[Mike Jackson]

So the existing liners in the first post have now turned into new liners. Am I alone in smelling a rat?

If the liners are new the obvious course of action is to speak to the manufacturers and ask them how they recommend that the bottom is sealed. Alternatively you could get the hump because you haven't given people the full facts who then try and give you the correct advice.

 

[OGBUzzard]

Hi sorry for the delay but here are the photos of the engineer's solution.

 

[tamz]

Re: gas fire regs gather hood/closure plate?ffs

Lovely!
ffs

 

[OGBUzzard]

We had a metalwork company make up some custom fittings that are just small Enough to slide up inside the liner, and we sealed it with fire silicone at the joint with the liner, and screwed the plate with silicone seal too.

 

[Reg Man]

Looks good but, always helps if it has a tappered transition into the liner though.This reduces the resitance of flow up the chimney. It will probably work ok. flue flow test will find out.

 

[lame plumber]

next issue is whether a plasterboard fire enclosure meets gas/building regs as a suitable material

 

[OGBUzzard]

Double boarded then skimmed. According to Fire regs I think, this is dot and dabbed onto existing masonry. Apocalypse proof, Satan proof!

 

[topdog]

The above installation (fire plasterboard) This is not the correct fire resistance plaster board,
it should be pink in colour as my pic below (This is the correct one that should have been used).



NOT THIS ONE


from
topdog

next issue is whether a plasterboard fire enclosure meets gas/building regs as a suitable material

 

[OGBUzzard]

Double skinning provides the same fire resistance rating as a single skin on pink board, been accepted by ds on jobs for years. Can save you money if you have left over standard boards. Also I did mention it was dot and dabbed onto existing masonry so there's no timber behind it to catch fire. I only posted the photo to show what I was talking about in the original question, because the answers weren't quite what I was looking for, we got there in the end though, thanks for all the answers anyway.

 

[OGBUzzard]

In fact I have seen the following para in many risk assessments and FSOs that I have worked with are in agreement that for existing buildings, this would be acceptable:

"...overboard the existing ceiling or apply directly to the joists either one layer of 15mm fire rated plasterboard or two layers of 12.5mm fire rated plasterboard with overlapping edges, jointed and sealed, installed by a competent person."

 

[Reg Man]

No no no no not plasterboard in a chimney system. tell me its not! Suitable material for flues/chimney's.

 

[topdog]

I always use LS board, FIRE RATED PLASTERBOARD IS USED ON THE FRONT OF THE CHIMNEY BREAST ONLY (Dob & Dab, Then skim plaster over board.
LS board used internally.
topdog

No no no no not plasterboard in a chimney system. tell me its not! Suitable material for flues/chimney's.

 

[lame plumber]

In fact I have seen the following para in many risk assessments and FSOs that I have worked with are in agreement that for existing buildings, this would be acceptable:

"...overboard the existing ceiling or apply directly to the joists either one layer of 15mm fire rated plasterboard or two layers of 12.5mm fire rated plasterboard with overlapping edges, jointed and sealed, installed by a competent person."

you seem to be discussing how to finish a ceiling to a finish to give an hours fire resistance, ceilings arent fireplaces and builders openings! it also mentions competent person!!! nuff said

 

[OGBUzzard]

Thanks for all the advice I just posted the photos to help clarify a few things, anyway the building inspector gave it the nod so all's well that ends well. 🙂

 

[Reg Man]

Interesting talk about plasterboard. On the chimney breast externally in the room all OK. Within the chimney opening it is not suitable. General fire resistance on plasterboard is 30 minutes. This is tested under conditions in event of a fire, this does not confirm suitability as a long term fire resistant material . Plasterboard will degrade at a fairly constant rate when exposed to long term exposure to heat and moisture (the conditions we find in chimneys). The best solution if you need to use a board, is a proper fire proof boarding, like superlux, masterboard ect.

I was involved with assisting an HSE prosecution against a fairly large business some years back, wher the contractor constructed plasterboard in glback boiler openings on about 100+ properties. They got very large fine and had to strip all the boilers out and brick the side wall openings up properly.