Chim Chim Chimney, Chim Chim Chimney...

[atlasfever]

Hello All,

And.... a chimney question!

Background: Georgian, 1st floor flat, 2 stacks, and 3 more floors above me
Goal: 2 working gas fireplaces. I will not be using them every day, and it's not a real source of heat, so in the end, it's for pleasure and I'm not fussed if I need to have a reduced heat output/flame size, etc if it can have a knock on cost savings on the flue lining choices.

Question:
I have had smoke tests done on both stacks (with are at either side of 2 connected rooms), and both have good draw. One has a breach (already identified) and one does not have a breach, but the flow was a bit restricted. The contractors suggested that sum serious cleaning is required.

I have called around and understand:
1. The Guild of Chimney Sweeps (I love england for such associations says that a proper sweep needs to take place. I called around and price seems to be about £220 for both stacks.
2. I then need to line the flues. There can be two ways, a 7inch liner or something called aFuronflex thing, which is basically coating the inside of the flue, which will allow for (likely) a larger flue all the way through. The liner approach seems to be about £2,000 plus vat and the higher end liner is £3 to £3,500 plus vat.

So: Any thoughts? I really would like to just do the fair minimum (as in, no need for over kill, but not to little that I create a hazard either). For something that is a 'nice to have,' I don't want to invest more than necessary.
Note: Roof top/chimney pots accessible via staircase/roof, so no scaffolding necessary.

 

[Sonyaclegg]

I can't answer the question but what is wrong with not lining the chimney and using them? My friend has a firegrate ( if that's the term to use) and her chimney isn't lined and she gets on just fine with it! Everyone wants to line my chimneys too!

 

[JoceAndChris]

I'm glad you asked that question as I don't understand it either. I'm pretty sure our chimneys aren't lined and fires have been lit almost daily for 200 years with no problems.

 

[plasticpigeon]

I think the lining is to stop any flue gases escaping into the house. If the lining is insulated it also helps stop condensation. I can see some chimneys in my house have parging that stops the gases leaking, but the ones that have been used more have less parging. I guess it falls off over time or gets brushed off when the chimney is swept. I'm planning to use my fires a few times a year so I can't be bothered with lining, but I will be bothering with CO monitors.

 

[Penners]

I think you need to be a bit clearer about what type of "gas fireplaces" you have. And if you want chapter and verse on the flue requirements for them, I should get on to the manufacturers' websites and look for "support" With a bit of luck this area will offer downloads of technical manuals for all products. You should find clear flue recommendations in there.

 

[MdB]

http://www.bbc.co.uk/news/uk-england-cornwall-21700005

Whatever you do - get a CO monitor (£15).

 

[Sonyaclegg]

We have co2 monitors where we are living now and will fit some in the new house. They should be in use as much as smoke detectors and, perhaps, maybe they will be one day.

 

[atlasfever]

Well, I think you're probably right, I'm not very clear, b/c I'm rather confused )

Let me try again:
1. I would insert a gas fireplace. I believe it's the 'flip a switch' and the flames start. And, it's an insert that you put into the original fireplace (removable anytime). And, somehow, the flames are open, not hidden behind glass.
2. A few contractors have indicated that a 'gas safe' guy/gal will likely only install if there is a vent installed (i think they mean there is a fresh supply of oxygen? for the fire?
3. depending on the size of gas flame or something, then i would need a 7inch or 8 inch or the more sophisticated liner.

yes, i won[t use it much, but i think i can't install gas unless it's lined. fair enough, safety is paramount.

 

[plasticpigeon]

Will it be something like this???

http://www.stovax.com/fireplaces/classicfireplaces/classic_fireplaces/cast_iron_hob_grate_inserts/regency_hob_grate.aspx

I'd imagine with gas that it would need to be lined. Building regs are all available online. I think this is the right one

http://www.planningportal.gov.uk/buildingregulations/approveddocuments/partj/

 

[agbagb]

At those kind of prices for flue lining I would be look at "Flueless" catalytic gas fires.

 

[Owain]

I wouldn't touch a flueless gas fire with a bargepole and neither will most Gas Safe fitters.

There's a reason why Victorial ladies swooned a lot, and it's not maidenly modesty, it's almost certainly carbon monoxide poisoning from the gas lighting.

http://news.bbc.co.uk/1/hi/wales/south_east/5413478.stm

 

[Penners]

There's a reason why Victorial ladies swooned a lot, and it's not maidenly modesty, it's almost certainly carbon monoxide poisoning from the gas lighting...

...combined with over-tight corsetry!

 

[atlasfever]

Hello All,

I usually just ask questions, but thought to share info this time
I met with a helpful guy from 'chimney care' (supposed to be a quite good company) who explained the following:
A. For one room, with a gas fire more than 6.9w output, you need a fresh air vent (no vent needed if 6.9 or less)
B. For two rooms that open to each other, each with a fireplace of less than 6.9w output, you still need a fresh air vent per room. Only if there are doors between do you go back to the rule described in "A"
C. The fresh air vent is fixed open.

Interesting. It doesn't make much sense to me why two rooms that are connected, each with their own fireplace do need two vents, but 2 rooms that are separated by a door, each still with a fireplace, don't need a vent at all (assuming 6.9w output). But, no matter. I'm adding doors, so that part is solved for me.

He also said a 6.9w output gives a good look, but not necessarily much heat. This is fine for me, as it's more decorative than anything else. And, I have to chuckle at thoughts of insulation, glazing, heating, etc and then, an open vent all year long. Hilarious. I assume building regs, etc require it for good reason, but you have to laugh at that idea. Perhaps in the days of only fireplaces, they produced much more heat than one would lose via a vent.

I will provide further info on the flue linings as I receive it. So far, he suggests a camera survey (down the stack), and then hopefully a flex lining after.
Cheers

 

[MdB]

He also said a 6.9w output gives a good look, but not necessarily much heat.

We have 6kW for the entire house....

 

[atlasfever]

Even more info So, I'll be toasty warm on the flip of a switch

 

[Penners]

He also said a 6.9w output gives a good look, but not necessarily much heat.

He's dead right. I suspect you mean 6.9kW!

 

[Keith Bowman]

He also said a 6.9w output gives a good look, but not necessarily much heat.

He's dead right. I suspect you mean 6.9kW!

Doesn't make much sense to me. Wouldn't 6.9kw be a bit much for a domestic gas fire? Someone said above (can't get back to the post now without coming out of this one) that it would be more than the output for his whole house. Our oil fired boiler is only 18-25kw. But 6.9 watts would be smaller than a sidelight bulb in my car!

 

[atlasfever]

People, you have to understand that I know nothing about build technicals

You're right, it was kW.

 

[atlasfever]

Hello,

Could anyone explain how Class 2 or Class 1 glue and fire apply to the concept of 6.9kW fire?

I understand that a Class 1 flue is 7" or more, and allows for a class 1 size fire (but, what does this mean????)
And, a Class 2 flue is a 5" liner, and allows for a class 2 fire (but...again, what does this mean?)

I know about the 6.9kW threshold for size of heat output, and how it relates to whether you need a free flow air vent --- but, how this connects to the class 1 or 2 flue...or fire.. no idea.

Thanks for feedback.

 

[MdB]

My understanding - maybe incorrect, check first....

Class 1 liners are for high temperature operation and are made from two layers of stainless. Inside is normally smooth and outside is ribbed. Used for oil, gas, wood, coal etc.

Class 2 liners are for flue temperatures below 250°C are made from a single layer of stainless and are only for oil or gas appliances which state they are suitable for use with a class 2 liner.

Size of liner is to match the appliance.