what size drill bit for 15mm copper pipe through wall?

[dragonfly101]

sounds like the answer is in the title I know, but do I need to allow extra width for heat expansion? This is going through a 200mm internal wall. Also I read somewhere that copper pipe going through masonary should be sheathed in plastic pipe to protect it from corrosion, is this correct>

 

[JBPHS]

I'm assuming its not for gas?

Drill hole 25mm diameter. Use 22mm copper pipe to sleeve the hole, (seal around 22mm with mortar, etc. Run 15mm through the 22mm, seal with silicone. Job done.

James.

 

[Charnwood]

Sleeve with overflow pipe.

 

[footprints]

Yup use plastic, brickwork will corrode a copper sleeve.

 

[newbuildinstaller]

110mm soil should give you a bit room for maneuver fill with expanding foam

 

[Dan Robinson]

Blo0dy ECO cowboys!


At least use Plumbers Mait and do the bodge properly .

 

[Blagard]

Yup use plastic, brickwork will corrode a copper sleeve.

No it won't if it is OPC in the mortar and the clay in the bricks is pretty inert!
Sleeving copper is mainly to allow movement and plastic overflow is cheaper than a copper sleeve so it is common sense to use it. but for reference read:

http://www.copper.org/applications/plumbing/techcorner/problem_embedding_copper_concrete.html
http://www.copper.org/applications/...tube_concrete_thermal_expansion_allowance.pdf

 

[footprints]

Yup use plastic, brickwork will corrode a copper sleeve.

No it won't if it is OPC in the mortar and the clay in the bricks is pretty inert!
Sleeving copper is mainly to allow movement and plastic overflow is cheaper than a copper sleeve so it is common sense to use it. but for reference read:

http://www.copper.org/applications/plumbing/techcorner/problem_embedding_copper_concrete.html
http://www.copper.org/applications/...crete_thermal_expansion_allowance.pdf[/QUOTE]

Sorry Blagard I have to disagree, any brick that contains black particles, cinders, or made of breeze block, will chew through copper in a few years seen it loads of times. No way of telling what the OPs wall is, so playing safe and using plastic makes sense.

 

[JBPHS]

Yup use plastic, brickwork will corrode a copper sleeve.

No it won't if it is OPC in the mortar and the clay in the bricks is pretty inert!
Sleeving copper is mainly to allow movement and plastic overflow is cheaper than a copper sleeve so it is common sense to use it. but for reference read:

http://www.copper.org/applications/plumbing/techcorner/problem_embedding_copper_concrete.html
http://www.copper.org/applications/...crete_thermal_expansion_allowance.pdf[/QUOTE]

Sorry Blagard I have to disagree, any brick that contains black particles, cinders, or made of breeze block, will chew through copper in a few years seen it loads of times. No way of telling what the OPs wall is, so playing safe and using plastic makes sense.

Oh yeah, I keep getting called out to 1950's houses with unsleeved copper pipes running through brick walls due to them leaking caused by the brickwork.

 

[footprints]

I can only speak as I find I have certainly had it in houses in London and the suburbs.


A extract from the link given to copper.org

"However, copper should be protected when it comes in contact with concrete mixtures that contain components high in sulfur, such as cinders and fly-ash, which can create an acid that is highly corrosive to most metals including copper."

Guess we will have to agree to disagree on that one

Regards,
footprints

 

[Blagard]

Guess we will have to agree to disagree on that one

Well not quite you didn't read my post properly. I referred to mortar using OPC - which so far as I know, is the most common type of cement. The links I posted covered situations where other chemicals/cements can attack the copper.

I was not saying you should not sleeve pipes - I said the reason is to allow movement as opposed to corrosion by ordinary portland cement in mortar.

Remember a copper pipe that has been abraded enough to start leaking will green up and look like corrosion. I have not seen a single copper pipe corroded by mortar and if you ever look at short copper waste pipes in old properties you will find them cemented in, no sleeves, no corrosion and no movement to speak of.

But if in the face of research you disagree then you are entitled to

I have only ever come across a OPC substitute once - Where PFA was used (Pulverised Fuel Ash) and that takes a long time to reach strength in the concrete piles we used it for. You might have a point on some blocks, I'll need to check that

 

[footprints]

I quite agree Portland cement’s not the problem it’s the aggregate mixed with it, or make up of the brick/block it is holding together.

One instance I remember was going to change an outside tap and where the pipe was touching the brick It was the type of brick that has black areas in it (and is a real sod to drill ) the pipe was badly corroded, wafer thin in fact.

Breeze block is formed from clinker ash etc whatever they can get hold of, I have certainly seen that attack pipes too.

I was taught to protect pipes in screed with Synthaproof or Denso, but I have certainly seen plenty of unprotected pipes that are good as gold years later, it just depends on the medium it is in.

 

[dragonfly101]

thanks for all the replies on this, so it looks like if I don't know exactly what my wall is made of then I'm safest going with plastic pipe - I assume standard 'overflow' pipe will be a good diameter for a 15mm copper pipe? And then I fill the gap between the pipes with silicon sealent.

Is there any particular type of silicon sealent I should use?

Also, do I need something to stick the plastic pipe to the hole if it's not a tight fit? Maybe some unibond glue?

 

[newbuildinstaller]

christ its a pipe through a hole not open heart surgery.

Though to be fair if you can find it I always use "sleeving" silicone when filling a sleeve. comes in 10cl tubes

 

[footprints]

Yes normal silicone if you have some around, there are special products like FJC compound but don't worry with that, you will be fine with most sealants, mind you a paintable sealant might be best for internal walls to allow decoration. Paint dosen't stick to silicone well.