Looking for a book on plumbing.

[epsilonGreedy]

I waste hours online trying to understand the array of plumbing systems available and then more hours at Screwfix.com finding converter bits between different systems and pipe sizes. I think part of my problem is working out which are legacy systems encountered by plumbers in the field v. what is applicable to a cleansheet new build.

 

As an example here are today's challenges:

1. I want to refit a large chunky copper compression fitting to the end of a 25mm MDPE pipe and Screwfix only offers 22mm and 28mm olives.
2. Should such an MDPE/Copper joint have a plastic or copper or plastic pipe insert.
3. How do I choose between 22mm or 15mm HEP20.

 

[Jeremy Harris]

3 minutes ago, epsilonGreedy said:

I want to refit a large chunky copper compression fitting to the end of a 25mm MDPE pipe and Screwfix only offers 22mm and 28mm olives.

 

 

To fit a 22mm copper pipe to 25mm MDPE (both have virtually the same bore) then you need an MDPE to copper adapter, like this: https://www.screwfix.com/p/jg-speedfit-ug602b-mdpe-copper-adaptor-25mm-x-22mm/49708

 

(not a recommendation, just the first hit on the Screwfix site)

 

 

3 minutes ago, epsilonGreedy said:

Should such an MDPE/Copper joint have a plastic or copper or plastic pipe insert.

 

 

 

MDPE only accepts plastic inserts.

 

8 minutes ago, epsilonGreedy said:

How do I choose between 22mm or 15mm HEP20.

 

 

If you wish to use HEP2O rather than copper (I thought you wanted to use copper, from the reference to copper compression joints?) then the guidance is the same as for copper, you choose the size based on the expected flow rate.  Main supply pipes feeding several other pipes should be in 22mm, pipes only supplying a basin tap, sink, toilet cistern etc can be 15mm (or even smaller for some of them, where a faster warm up time for hot water is required).

[PeterW]

Ok so @Nickfromwales and me agree on one thing.... Hep2O all the way unless it’s on show where copper rules ..

 

But.. unless you’re having a boiler where you can’t use anything but copper for the metre nearest the appliance, Hep2O will do everything for you and it’s quick and easy. 

 

I suggest you start with the Site Guide and go to Screwfix and buy a bag of inserts, a couple of tees, a couple of elbows, a demounting set and a connector and a length of 15mm pipe and sit in the van one evening and practice ..! 

 

If you get stuck you can always shout as I’m not far down the road.  

[ToughButterCup]

Tried BuildHub?   All the right words, but not necessarily in the right order.

[Ed Davies]

1 hour ago, PeterW said:

But.. unless you’re having a boiler where you can’t use anything but copper for the metre nearest the appliance, Hep2O will do everything for you and it’s quick and easy. 

 

Or solar thermal.

[PeterW]

25 minutes ago, Ed Davies said:

 

Or solar thermal.

 

Yep thanks @Ed Davies - forgot that one but it is in the site guide about what and where 

[epsilonGreedy]

19 hours ago, PeterW said:

Ok so @Nickfromwales and me agree on one thing.... Hep2O all the way unless it’s on show where copper rules ..

 

 

This is interesting because after posting yesterday I decided I had reached an unproductive mental road block re. plumbing so I drew a diagram and headed off to my local traditional iron mongers which is a quaint establishment, think of the Two Ronnies 4 candles/fork handles sketch. The iron monger is run by an ex. plumber and he likes offering advice to a near clueless self builder.

 

Like any pro he knew there were multiple options for hooking together 25mm MDPE, a washing machine and 1/2" copper garden tap. Since I have copious amounts of MDPE pipe onsite and a box of horrible PhilMac connectors that I will not trust in the main build, my new Worker's Onsite Laundry Facility (Garden Shed) is now to be plumbed as follows:

• Blue 25mm MDPE pipe > PhilMac stop tap > more 25mm pipe > PhilMac T connector.
• Washing machine T branch = MDPE to ¾ thread adapter" as recommend by @Miekin another thread > standard washing machine flexible cold feed hose.
• Garden tap branch = 8 foot length of 25MM MDPE pipe along internal shed wall > copper compression adapter down to 15mm copper pipe through shed wall > 90 degree copper compression elbow > 6" of copper 15mm pipe > garden tap.

 

And on to Hep20. The said ex plumber / shop owner offered a strong dislike of Hep20 because of rodents. To prove this he pointed to an area of the shop ceiling and explained how rodents chewed through a plastic pipe next door which led to the flooding of the shop. I wish I had not heard his views because I had previously settled on Hep20 due to the system being favoured by regulars here.

 

What is the forum's viewpoint and the rodent Hep20 risk?

[epsilonGreedy]

19 hours ago, AnonymousBosch said:

Tried BuildHub?   All the right words, but not necessarily in the right order.

 

 

My plumbing questions feel too lowbrow compared to many hi-tech debates here, e.g. where would I favour a 40mm waste pipe over 32mm?

[Jeremy Harris]

21 minutes ago, epsilonGreedy said:

What is the forum's viewpoint and the rodent Hep20 risk?

 

How are rodents ever going to gain access? 

 

Even a house built to just meet building regs airtightness isn't going to (or at least shouldn't) have any holes large enough for a mouse to get through. 

[epsilonGreedy]

21 hours ago, PeterW said:

I suggest you start with the Site Guide and go to Screwfix and buy a bag of inserts, a couple of tees, a couple of elbows, a demounting set and a connector and a length of 15mm pipe and sit in the van one evening and practice ..! 

 

 

Thanks, will do. I took that approach with my first MDPE underground mains feed plumbing which went well until I hit the PhilMac pit of despair. The sunny uplands of Plasson and Floplast are ahead.

 

The good thing about living onsite is the someone like me, who has never changed a tap washer in his live, can practice on static caravan plumbing then gravitate to gardenshed plumbing before the important stuff starts.

 

I have already learned:

1. The plastic in pushfit waste pipes is very different to that in solvent weld pipe.
2. A 110mm pipe end chamfer tool is essential.
3. The @JSHarris method of marking a 110mm pipe square for cutting is brill.
4. 25mm MDPE pipe does not like tight bends or being persuaded to connect across any misalignment.
5. Before commencing any underground mains plumbing fill a few buckets of water for cleaning joints before turning off the meter stockcock and cutting the pipe.
6. The thickness of my index finger under a 1.2m spirit level = a 1 in 80 soil pipe gradient.
7. You don't need any fancy stockcock tap extension arm to reach a modern meter stopcock at the roadside because they have one built in.
8. The degree of technical advancement between PhilMac connectors and the same from Plasson is equivalent to that between a Sedan Chair and a Tesla automobile.
9. Brut force is required to securely crimp a copper olive down into 25mm MDPE pipe, I had one connection at mains pressure pop open under the caravan though fortunately I heard the water within 2 minutes so just a minor flood.
10. Freezing risks with plastic pipe are overstated ( at-least for temporary setups).

Edited April 20, 2019 by epsilonGreedy

[epsilonGreedy]

20 minutes ago, JSHarris said:

How are rodents ever going to gain access? 

 

 

They are equipped with on-board neural networks of moderate complexity that have been trained across millions of years of evolution to find the one chink in your thermal envelope.

[PeterW]

2 hours ago, epsilonGreedy said:

What is the forum's viewpoint and the rodent Hep20 risk?

 

There isn’t one. Rodents don’t eat plastic pipe, not when in a house there are more nutritious and easily obtained food stuffs. I certainly haven’t seen any Hep2O rodent damage. 

 

Could it be that copper is over twice the price, 10 times the complexity and he happens to sell it perhaps .......?

[epsilonGreedy]

31 minutes ago, PeterW said:

There isn’t one. Rodents don’t eat plastic pipe, not when in a house there are more nutritious and easily obtained food stuffs. I certainly haven’t seen any Hep2O rodent damage. 

 

 

A Google search for "Hep20 rodent" suggests there is a problem. My inclination is still towards plastic based on diy simplicity, I am just trying to quantify this opposing view heard yesterday.

 

32 minutes ago, PeterW said:

Could it be that copper is over twice the price, 10 times the complexity and he happens to sell it perhaps .......?

 

 

He commented on price saying the extra cost of plastic connectors offsets the copper price overhead.

[PeterW]

30 minutes ago, epsilonGreedy said:

A Google search for "Hep20 rodent" suggests there is a problem.

Are they the posts on the plumbers forum from 2009...??

 

mice will eat cable and  thin stuff first as it’s soft. TBH I would be more worried about how a rodent had got into a ceiling space than worrying what it’s eating .. you’re brick and block so all joist ends will be sealed to the cavity, soil stacks are through concrete floors, and even if you dot and dab the walls you’ll have no runs for them to get into the spaces. If you’re that worried run everything in 20mm conduit or use conduit pipe. 

 

30 minutes ago, epsilonGreedy said:

He commented on price saying the extra cost of plastic connectors offsets the copper price overhead.

 

That’s rubbish. 

 

Copper tee is 75p, if I’m quick I can probably prep and fit a tee in less than 10 mins from straight runs of copper and end feeding. At £25/hr it means to fit a copper tee is probably £4.75 in total. Same in Hep2O is £2.60 and takes 2-3 mins most to make off so £3.60 or so. That’s 30> cheaper.

 

Then factor in pipe at twice the price per metre; not being able to thread through joists etc, not having to form elbows to run from ceilings to walls; not having to joint every 3 metres ..? The list goes on. 

 

I can probably teach a reasonably novice DIYer to use Hep2O in an afternoon to the point that I would be happy leaving them to do a lot of it. To learn to do copper properly takes weeks - get it wrong and it can mean an hours work to undo everything to get to a joint.  

 

Sadly your ex plumber is the sort that probably still sells sanitary putty and suggests it’s better than McAlpine pan connectors .... just because that’s how he’s always done it .. NAPHE used to be full of them ..!

 

Don’t get me wrong, copper has its place and I still love using it but I’ve been using it for probably near 40 years. I also still know how to lead weld and do formed sockets in lead and copper pipe joins - but there are much better modern alternatives ..!

 

If you really want the copper on show but don’t want to learn to solder or don’t want to set fire to a kitchen cabinet then use the Tectite Sprint fittings. Look neat, work the same as Hep2O but they are not demountable so it’s measure 5 times and cut once ..! 

 

I’ve done a 3 bed recently with 22mm main feeds, 15mm to bathroom en-suite downstairs WC kitchen and utility and I reckon the total cost of Hep2O pipe and fittings is about £180. I’ve then spent around £160 on copper just to do the plant room ..! Plant room took a couple of days to do, rest of the house the same .. work that out ..!

 

[ProDave]

Re rodents.

 

Our last house was built with a standard cold roof, i.e insulation at ceiling level and loft space cold, and ventilated.  We didn't know any better then, that was the way every house I have ever lived in was done.  We had mice in the loft regularly and kept a pot of rat poison to sprinkle regularly.  I think we worked out mice could climb up the outside of the roughcast walls and get in through the eaves or soffit air vents.  A mouse can get through a small hole, even the hole in an air brick.

 

There seemed no way to stop them so send the cat up periodically or poison was the only way. It is imho now, a flawed way of building. 

 

The new house is built with a warm roof, i.e insulation between (and above) the rafters.  result ALL the inside of the house (even the bit we have partitioned off as loft space) is outside the reach of mice.  No more little feet scurrying about in the loft and no more poison needed.

[epsilonGreedy]

16 hours ago, ProDave said:

A mouse can get through a small hole, even the hole in an air brick.

 

 

Even a modern plastic airbrick?

 

16 hours ago, ProDave said:

We had mice in the loft regularly and kept a pot of rat poison to sprinkle regularly.  I think we worked out mice could climb up the outside of the roughcast walls and get in through the eaves or soffit air vents.

 

 

We had mice and squirrels in our previous rental house.

[epsilonGreedy]

17 hours ago, PeterW said:

If you’re that worried run everything in 20mm conduit or use conduit pipe. 

 

 

Just been looking at the Hep20 Site Guide you linked to earlier, would the conduit you mention be the red "pipe in pipe" product shown in that guide?

 

I like the guide BTW, part of the challenge of self building is to avoid wasting time by eliminating options and focusing.

 

Until now I had not realized that Hep20 was a pushfit system, previously I had only encountered that on boats.