Gas Pipe Sealant

5hpr

Hi all,
I had the kickboards off in the kitchen and noticed a draught coming from the corner of the kitchen.  On checking the outside, I feel its coming from the gas pipe that comes into the property.  Please look at the attached picture (gas pipe entering property on the wall and going to gas meter on the left).  There is a gap around the pipe where the sealant has retracted around the main wall.  A colleague at work said to seal it with 'mastic' but can't seem to find the right stuff.  He said it was weird that this happened considering the gas pipe doesn't get hot//cold so it's strange tor the current sealant to behave this way?

I am not great a DIY but if someone could kindly inform me if it's OK to seal this hole (or does the gas pipe need this space around it?  I don't need to remove the existing stuff?  Can I just use a cartridge gun and a tube of something?  If so, would you kindly be able to show me what I need, ideally from B&Q?!

I should probably finishing by saying the house is a new build, 7 years old (Taylor Wimpey).

Many thanks all!

Alter_ego

Looks like "No more nails" or similar
I'd use silicone  (in case you ever need to remove the pipe)

5hpr

Alter_ego said:

Looks like "No more nails" or similar
I'd use silicone  (in case you ever need to remove the pipe)

Brown silicone?  It's at the front of the property so it'll make it blend in with what's already there?  Would this be OK:

Sika Sikaflex EBT+ All-Weather Sealant Brown 300ml | Weatherproof Sealants | Screwfix.com

Alter_ego

5hpr said:

Alter_ego said:

Looks like "No more nails" or similar
I'd use silicone  (in case you ever need to remove the pipe)

Brown silicone?  It's at the front of the property so it'll make it blend in with what's already there?  Would this be OK:

Sika Sikaflex EBT+ All-Weather Sealant Brown 300ml | Weatherproof Sealants | Screwfix

Seems fine to me.

jefaz07

Seal it with fire cement 

chrisw

It's strange how that old sealant has been applied. It looks almost as though there was a bigger pipe or something through or round the hole at some time.

But yes, brown silicone will be fine.

jefaz07

chrisw said:

It's strange how that old sealant has been applied. It looks almost as though there was a bigger pipe or something through or round the hole at some time.

But yes, brown silicone will be fine.

It’s not that strange. I think the book says the annulus between the sleeve and brick needs to be sealed. And I pen on one end...I could dig out my books. 

Anyway use this;

https://www.toolstation.com/fire-cement/p38992?store=G2&utm_source=googleshopping&utm_medium=feed&utm_campaign=googleshoppingfeed&gclid=Cj0KCQiA5bz-BRD-ARIsABjT4niX0FuL8IDRK2ofXaw1Xong4H_RZfg8_0SSJOz32E4HOZYSZ7HTQfcaAjIwEALw_wcB


You have to use non setting fire resistant compounds. 

Jeepers_Creepers

As pointed out by others, that does look like a neat circular shape in the sealant, so I wonder if there was a collar of some sort stuck on there that's fallen off - a bit like the pipe collars you get for rad pipes coming up from the floor?

Anyhoo, I would use frame sealant 'cos I'm Scottish. Yes, it's cheap. Actually, I'd avoid silicone anyway as the acetic acid will likely tarnish the copper and make it look unsightly - unless you love Verdigris - and, frankly, there's just no need for anything like sili anyway.

Certainly don't use fire cement or mortar.

Go to your local Screwfix or hardware store and buy the cheapest tube of exterior frame sealant you can.

Hmm, a thought; gas pipes are not meant to be run inside sealed cavities and spaces (in case they leak and cause a gas build up), so I wonder if the hole was designed for a special collar that allowed a teeny bit of venting? I think what I would do, then, is to seal that pipe on the inside of your wall only. That'll stop the draught coming in, but still allow the pipe to be vented.

Lorian

I'm no gas expert but I'm not sure it should be sealed on the outside if thats a (oversized) sleeved insert.
I presume it has an earth strap (primary bond) attached inside the meter box?

jefaz07

Jeepers_Creepers said:

As pointed out by others, that does look like a neat circular shape in the sealant, so I wonder if there was a collar of some sort stuck on there that's fallen off - a bit like the pipe collars you get for rad pipes coming up from the floor?

Anyhoo, I would use frame sealant 'cos I'm Scottish. Yes, it's cheap. Actually, I'd avoid silicone anyway as the acetic acid will likely tarnish the copper and make it look unsightly - unless you love Verdigris - and, frankly, there's just no need for anything like sili anyway.

Certainly don't use fire cement or mortar.

Go to your local Screwfix or hardware store and buy the cheapest tube of exterior frame sealant you can.

Hmm, a thought; gas pipes are not meant to be run inside sealed cavities and spaces (in case they leak and cause a gas build up), so I wonder if the hole was designed for a special collar that allowed a teeny bit of venting? I think what I would do, then, is to seal that pipe on the inside of your wall only. That'll stop the draught coming in, but still allow the pipe to be vented.

OP...do use fire cement. 

It’s what we use to seal pipes all the time. I’m telling you as someone who does the job and uses this stuff. I’m not guessing I’m telling you the exact answer to your question. 

Read British Standard 6891 (Installation of low pressure gas pipework of up to 35 mm in domestic premises. 

A little snippet is;
‘The annular space between the pipe and the sleeve shall be sealed at one end to the pipe with flexible fire resistant compound’

That IS NOT window sealant, not for for purpose. 

The nice little circle is sealant is the annular space between sleeve and brick. That has been sealed. The has been no little decorating cap!!

jefaz07

Lorian said:

I'm no gas expert but I'm not sure it should be sealed on the outside if thats a (oversized) sleeved insert.
I presume it has an earth strap (primary bond) attached inside the meter box?

If it’s an outside meter box an earth can be inside as close as reasonably practicable to the entry to the property. 

The ‘within 600mm and before any tee’ doesn’t apply.