Oil Boiler Flue location

[RichJS]

Due to lack of foresight and knowledge of the regulations we are having an extremely difficult time trying to find a suitable location for a new oil boiler in our extension. Despite it being a substantial construction it seems that the regulations governing flue distance from window, doors walls or access to bends in extended pipework is thwarting us.

With our oil boiler installer we have found one possible location but it is not ideal as it takes up space allocated to other things and is a long way from connection to the existing heating system. One of the issues with locating it in a more convenient position is that the flue exiting ground storey roof would be closer than 750mm from an adjacent first storey wall. Oil boiler man said that the pipework needs to be 750mm from the wall but reading the Approved Document J I'm not sure this is correct because it only refers to the outlet from the flue not the pipework. So my question is could the flue exit the ground floor roof closer than 750mm from the first storey wall and then kick out so that outlet was 750mm from the wall?

 

[RichJS]

Actually looking at Table to Diagram 41 again it does say "From a vertical structure to the side of the terminal - 750mm" so this probably does mean the flue pipe and not just the outlet

 

[simond]

Grant UK do a range of flues that can be run externally, with a 90 elbow on top.

Perhaps you should try another installer if your current one is out of ideas?

 

[RichJS]

what I really need to know is whether all of the flue pipe has to be 750mm away or just the outlet. If you imagine a wall with a pitched roof running down it and the flue existing the pitched roof say 300mm from the wall. Could the pipe then bend say 45 degrees and extend 600mm upwards (minimum distance from intersection with the roof) and 750mm outwards. Would this be allowed?

 

[Agile]

Both you and your installer seem to be confusing the terminal and the pipe.

Its the actual manufacturer whose requirements take priority.

The pipe can go where you like as long as the vertical terminal is 750mm from a wall.

Some flue systems allow a horizontal terminal supplied by a 90° elbow. But not all flue systems are permitted to have elbows or joints outdoors.

I am sure there is a suitable solution and the manufacturer would probably help but thats best shown as a photo or drawing as verbal descriptions are often difficult to follow.

Tony

 

[RichJS]

This is what I want to do. We can't come vertically up through the roof and terminate because we are too close to the vertical wall but our boiler installer is of the opinion that it's not juts the outlet from the flue but the pipe itself that has to be 750mm away from the vertical wall but I can't see what reason there would be for this?

Flue Sketch

• RichJS
• 7 Sep 2010
• 1

 

[Tipper]

Is there room in the roof space above the ceiling for the flue to do a short horizontal run using elbows and a short length of flue? This would depend on the make of boiler/flue used.

That way you would be able to place the exit through the roof in accord with the regs and it would look neater.

 

[RichJS]

Unfortunately not. There is only a sliver of ceiling space above the utility room. The dotted lines show the internal walls (sorry for the crappy sketch). The room to the right is a ground floor bedroom and has a vaulted ceiling so no loft space.

A possible solution we are considering is moving the internal wall back (the one to the left of the utility room door looking at the sketch) to give the 600mm clearance required from the door on one side and the opening window on the other so we could have the flue exiting from the side of the wall. As the internal block wall has already been built this would entail extra cost and is not popular with my Dad, who'll be losing space in his bedroom

With hindsight we should have made sure we accommodated the boiler position in the plans but to be honest I didn't think it would be this much hassle. Suffice to say the old boiler position would never have met the current regs!

 

[1CANHELP]

Due to lack of foresight and knowledge of the regulations we are having an extremely difficult time trying to find a suitable location for a new oil boiler in our extension. Despite it being a substantial construction it seems that the regulations governing flue distance from window, doors walls or access to bends in extended pipework is thwarting us.

With our oil boiler installer we have found one possible location but it is not ideal as it takes up space allocated to other things and is a long way from connection to the existing heating system. One of the issues with locating it in a more convenient position is that the flue exiting ground storey roof would be closer than 750mm from an adjacent first storey wall. Oil boiler man said that the pipework needs to be 750mm from the wall but reading the Approved Document J I'm not sure this is correct because it only refers to the outlet from the flue not the pipework. So my question is could the flue exit the ground floor roof closer than 750mm from the first storey wall and then kick out so that outlet was 750mm from the wall?

At present my company is fitting 4-5 oil installs a week on contract and I have never had any problems when siting a boiler, then again! we are OFTEC registered and TIMESERVED professionals who carry out site surveys, therefore, don't just bulldoze ahead without the relevant knowledge.

In saying all that, the make of the boiler would help, however, if you look at OFTEC Technical Book 3 and in particular BS5410 Part 1, there is a contradiction in how a pressure jet flue should be positioned with regard to adjacent structures/surfaces.

However, I believe that when they say structure they mean a structure not belonging to you i.e. not part of your house and when they mention surface they mean part of your property.

Item (F) From an internal/external corner or SURFACE or BOUNDARY alongside a terminal 300mm

Item(N) From a vertical structure on the side of a terminal 750mm

A pressure jet vertical flue terminating 300mm from an adjacent surface FOR EXAMPLE is no different to the horizontal terminal as in (F). in fact you could argue the POC's will dissipate more freely in the vertical fitment position.

This where the OP needs to employ a TIMESERVED professional who is OFTEC registered and they will make an informed judgment based on experience.

AND WHY ARE YOU FITTING THE STINKY OIL BOILER INSIDE WHEN YOU COULD HAVE AN EXTERNAL MODEL AND SAVE ANY HASSLE.

Oh I know, you'll be a short course idiot or DIY t1t trying to save a pound

By the way I hope the tank meets the requirements as all oil tank installations are now retrospective in the UK i.e large fines running into thousands could be on the cards should something happen.

All in all, fitting the vertical flue 300mm away from your surface as indicated in your diagram is no different to the horizontol min dimensions from a surface.

Just get it fitted or better still purchase an external model!

 

[Agile]

I think there has been some confusion in this thread between a vertical terminal ( which discharges in all directions and needs a clearance of about 750mm ) and a fanned concentric flue terminal ( which normally needs a clearance of 300mm ).

In the diagram, the flue is shown as discharging sideways to the house. The usual orientation would be to discharge away from the house towards the back garden.

Tony

 

[RichJS]

I think there has been some confusion in this thread between a vertical terminal ( which discharges in all directions and needs a clearance of about 750mm ) and a fanned concentric flue terminal ( which normally needs a clearance of 300mm ).

In the diagram, the flue is shown as discharging sideways to the house. The usual orientation would be to discharge away from the house towards the back garden.

Tony

Thanks Tony, that makes sense of the regulation.

 

[1CANHELP]

I think there has been some confusion in this thread between a vertical terminal ( which discharges in all directions and needs a clearance of about 750mm ) and a fanned concentric flue terminal ( which normally needs a clearance of 300mm ).

In the diagram, the flue is shown as discharging sideways to the house. The usual orientation would be to discharge away from the house towards the back garden.

Tony

Here we go! Tony the short course Biasi boiler specialist about to make an ar4e of himself again.

This condensing oil vertical flue arrangement is no different to gas whether or not it is discharging omni directional or out of a concentric flue horizontally.

At what f4cking force/velocity do you think a horizontal concentric flue emits at, christ! it's not a jet engine eflux.

Nobody seems to pick up on the different terminology i.e. structures and surfaces these are referred to diffrently as they are different.

To discharge the oil flue vertically at 300mm will pose no danger or cause no harm to the adjacent surface of the building, nor will it affect combustion.

how many NG-LPG vertical installations are closer than 300mm with no adverse affect.

This was my point, using a TIMESERVED appropriately experienced professional to undertake the installation is what the OP needs as they can draw on years of experience to get the job done safely.

Now Tony! when you achieve a fraction of my knowledge and experience...THEN you may question my judgement. Until such a time......peg your ears back and inwardly digest information from someone who is an experienced professional.

 

[1CANHELP]

I think there has been some confusion in this thread between a vertical terminal ( which discharges in all directions and needs a clearance of about 750mm ) and a fanned concentric flue terminal ( which normally needs a clearance of 300mm ).

In the diagram, the flue is shown as discharging sideways to the house. The usual orientation would be to discharge away from the house towards the back garden.

Tony

Thanks Tony, that makes sense of the regulation.

The OP chooses to ignore a timeserved professional who is OFTEC, GAS SAFE, MCS registered and NICEIC with many decades of experience.

Yet decides to listen to Tony Agile an ex BBC make up artist who undertook a short gas course and has served no recogniseable appropriate training. Also is not OFTEC QUALIFIED/REGISTERED so can't comment on oil installations.

You will find as many will tell you! Tony jumps in, makes a fool of himself and then dissapears only to return later when it's all blown over.

 

[RichJS]

1CANHELP - you seem to have lept to the conclusion that I am ignoring your advice. FYI I am not a DIY merchant out to save a few quid, nor an idiot, my installer is OFTEC registered and has so far not been condescending nor abusive. I posted the question in this forum to try and understand the regulations with respect to a flue adjacent to a vertical wall, I don't think that warrants being called an idiot but if that is the sort of attitude on this forum I won't be sticking around!

 

[1CANHELP]

1CANHELP - you seem to have lept to the conclusion that I am ignoring your advice. FYI I am not a DIY merchant out to save a few quid, nor an idiot, my installer is OFTEC registered and has so far not been condescending nor abusive. I posted the question in this forum to try and understand the regulations with respect to a flue adjacent to a vertical wall, I don't think that warrants being called an idiot but if that is the sort of attitude on this forum I won't be sticking around!

Well if he's OFTEC and experienced and by experienced I mean timeserved! not some butcher, baker or candlestick maker who has done an OFTEC course... Ask him for his grade card or where he served his apprenticeship....see what he says.

There are plenty short course trained gas and oil fitters without experience out their who haven't a clue charging you for their inexperience.

He should've know that the most obvious and sensible solution on a major extension was an external. Also, that putting the flue through as I explained will do no harm.

I am curt for a reason so don't take persoanl offence, I did not mean to imply you are an idiot, meerly people act like idiots when it comes to getting the correct tradesman/work doing.

If you're paying good money on a major extension..YOU shouldn't have to worry about or ask questions on an internet forum. The professionals you employed should be taking care of everything for you, after all....thats why you pays the money.

Two options:

1. Stick with boiler, put flue through as I suggest it will be fine...CHEAPEST.

2. Swap for an external model and save the hassle of penetrating roof and having a stinky boiler in your house, hell the guy doesn't even need to enter the house to service it. This will be more expensive, however, in the scale of the whole job peanuts.

By the way your installer has let you done badly, problems like these should have been sorted at the quotation stage.