Hey friends,

Apologies for my absence the last few weeks. I booked in a plasterer sooner than I probably should have and had a mad rush to get the room ready for him. The plastering is now complete so while I wait for it to dry out I'll catch up on the missed newsletters.

I left off previously with the new wall having been built but with a load of pipework that needed to be moved or removed. This is my first time plumbing but having watched the plumber do the bathroom I feel I'm ready to learn. First some...

Plumbing Basics

If you search copper vs plastic pipework on plumbing forums there's a noticeable shift from the early 2000s where plastic was mostly scoffed at to now where it's considered at least as good as copper and comes with a 50 year guarantee. Being 'push-fit' it's considerably easier than copper which suits me as a beginner. There are other benefits too. It holds the temperature of the water inside better than copper which is more conductive and the pipes have a more flexibility too which is helpful when making connections. The only downside to plastic that I've come across is that rodents can gnaw at it so it may not be as suitable for under your ground floor, though there are special conduits available. It also can't be used within the first metre of your boiler.

So having decided to go with plastic I needed to choose a brand. The new bathroom is plumbed with Polyplumb but that's not readily available from the places I frequent. Speedfit and Hep2o seem the most common and can be bought from Screwfix, Toolstation and Wickes. Speedfit is a little cheaper and seems to be well thought of so that's what I'll be using going forward.

Pipe

Speedfit offer both PEX and Polybutylene pipe for internal work. Both are barrier pipe which prevent oxygen from entering and causing corrosion so you can use either. PEX is a bit cheaper and more rigid than polybutylene which is often called 'layflat' pipe as it will straighten up more from the coil it comes in and you can use it to turn corners rather than using an elbow fitting. As I don't need much and have straight runs I'll be using PEX which you can also get in short lengths of 2 and 3m.

The two main sizes are 15mm and 22mm, just as with copper. As all the pipework I'm changing is 15mm I'll stick to that. I'm still getting my head around this choice but here's what I've learnt so far:

• For central heating pipes, imagine the boiler as the beating heart - it needs large 22mm diameter pipes (arteries) near it but as you get further away to individual radiators they can drop to smaller 15mm (capillaries). The same goes for your hot water cylinder.
• For hot water from the tap, the larger the pipe the larger the volume of water that sits in it. So if the tap hasn't been used in a while that water will be cool so you need to run the tap longer for hot water to start to come through. Annoying if you just want to wash your hands. 15mm might be the better choice here. Cold is the same if you want cool drinking water from under ground. Length of runs obviously matters here too but that's not always something you can change.
• Pipes to a bath are usually 22mm because they give greater flow so the bath fills up quicker. You may have exceedingly good pressure but to fill a bath in the same amount of time using 15mm it requires the water to come out quicker and probably splash everywhere. In regards to the point above it also doesn't matter so much if initially the water is cold because you'll regulate the temperature later while filling the bath. Hence why you might choose 15mm for a sink but 22mm for a bath.

If you've got any other good examples or explanations I'd be interested to hear.

Push-fit Fittings

Speedfit offer three main types of pushfit fittings: the coupler, the elbow and the tee. With these you can do pretty much every pipe run you need.

Here's how a connection is made.

Copper pipe is stiff so it can be pushed straight into the fitting. The cut does needs to be clean and perpendicular so use a pipe cutter, not a hack saw.

On the other side of the fitting is the new plastic pipe. It can be cut using a plastic pipe cutter in a quick snip. Plastic pipe is less rigid than copper so requires a superseal insert (the thing with the blue seals) to stiffen it up. These are simply pushed into the plastic pipe. I find a twist helps.

All pipes, regardless of brand, are a set external diameter (15mm, 22mm etc) and all pushfit fittings take these sizes so they are interchangeable. You can use a Hep20 pipe in a Speedfit fitting for instance. Hoowwwever! The internal diameters may not be exactly the same so you have to use the same brand insert as the brand of the pipe. I'll stick to Speedfit for everything but when I tap into the Polyplumb pipes to bring pumped hot and cold to the future side extension I can use a Speedfit fitting but will need to source some Polyplumb inserts.

Back to the diagram...

1. These are lines on the fitting to indicate where the pipe (with the insert for plastic) will come up to which will help you know that a) you've got the pipe in all the way and b) what length you need to cut the pipe to.
2. Once the pipe is pushed all the way in, tighten the screwcap to grip the pipe. Righty-tighty.
3. If you ever need to demount (undo) the connection you can push the collet inwards towards the fitting while pulling the pipe out. If the connection is hidden under a floor or in a wall it's a good idea to add collet clips to stop it from undoing on it own. They come in blue and red to help with identifying which pipe is which. You'll see them in action in a sec. I doubt professionals bother with them but hey, why not make it the best it can be.

Compression Fittings

The only other type of fitting you might need is a compression fitting such as on a radiator valve. They have a nut that you tighten and a copper olive that makes it watertight. The other difference is the type of insert. These ones allow the pipe to go further into the compression fitting than the superseal insert that you would use with the pushfit fittings.

Easy right? Speedfit's PDF guide has some useful diagrams and extra explanations.

Let's do some plumbing!

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I have 4 pipes to move: the cold from the mains, the cold from the tank (unpumped), the hot (unpumped) and the soil stack. We'll take each one in turn.

The Mains Cold

All the pipework below the floor level travel downwards in a service void boxed in in the kitchen. I'm happy for them to remain there as when we turn it into a hallway we can hide it behind cupboards.

The stopcock is also located there and travels upwards to the loft where it fills the tank and also loops back down to near the hot water cylinder to top up the boiler (the filling loop). Back at floor level it tees off and runs above the floorboards (previously hidden by the old bath) to serve the new bathroom's tap and toilet.

To isolate the mains was easy. I turned the stop-cock to the off position and drained whatever was left in the pipes from the bathroom sink. I then cut the copper pipe in the middle of the floor joist and used an elbow to bring the new plastic pipe to under the wall where I used a tee. I continued the pipe in the same direction to bring me to the other side of the wall where I put another tee with some future proofing:

I then had to use my hole saw bits to allow the pipe to go through the joists which replaces the old pipe which was above the floorboards.

And it looked like this:

See the new plastic pipe travelling up through the new wall? This is what the tee under the wall was for and I clipped the new vertical pipe to the stud using these.

Above the top plate of the wall I used a couple more elbows to meet back with the original copper pipe.

I turned the stop cock back on and all was working with no leaks. Wooo! My first bit of plumbing 🥳.

The Cold From The Tank

The mains cold pipe fills the tank in the loft. The tank serves three things: it fills the hot water cylinder; feeds our new shower pump to serve the bath and showers in the new bathroom (as I understand it you can't pump mains cold to increase pressure/flow, it has to be from stored water); and thirdly the tank serves the toilet and sink in the downstairs bathroom and also the washing machine - the pipe I need to move.

Now, I can't see the point of having tank water for these and they'll be just as good being on the mains, and less complicated.

To isolate I turned off the mains cold that feeds the tank at an isolation valve as it goes into the tank. Other options would have been to tie the ballcock in the up position or just turn the mains off at the stop cock.

But I still have a whole tank of water to get rid of so I did this at the washing machine outlet into a bucket.

Before continuing I couldn't help noticing the vast quantities of limescale in the loft tank. If Abi ever went up here herself rather than getting me to store and fetch things she'd no doubt be dismayed to discover she's been showering in this. So I took the opportunity to clean it using my wet and dry shop vac with the bag and filter taken out. No need to mention it, what she doesn't know can't hurt her ehy?

Better!

Despite it being cleaned up and in alright condition I should probably take the opportunity to replace it when I renovate the landing.

Anyway, now I needed to trace this pipe as it doesn't go down into the kitchen but through the wall instead (along with a branch of the hot water pipe).

It took me an embarrassing amount of time to find where these pipes lead as they were lurking in the corner of the garage hidden behind our clutter.

I cut this section of the tank-cold pipe out and popped on a stop end at floor level.

I then went to the downstairs bathroom and lifted the floorboards. Amongst the rodent nibbled lagging I discovered that the electric shower is served from the mains.

Fantastic. I can just tap into that and divert mains cold into the pipes that were served from the tank like so:

The stop end I put on the pipe in the garage stops the mains water gushing out of the old pipe.

So now the sink, toilet and washing machine are now all on mains water. If you're confused (wouldn't blame you!) here's a map of all the mains cold pipework now which I've made for my own sanity in case I need to meddle with it again:

Tank water - be gone with you!

The Hot

This pipe goes up from the hot water cylinder into the loft, across and down through the kitchen. However it branches off to serve the hot water tap on the downstairs bathroom sink and also the washing machine area.

Well, because I had a leak in the sink I'd already taken that out so for now I don't need hot water there and washing machine's don't need a hot feed either so I can get rid of that branch entirely. All that is required is to move the pipe into the new wall and then across to go down into the kitchen

To isolate I turned off the hot water at the thermostat and cranked the lever which supplies the hot water cylinder with tank water:

Then I did my pipework with a few elbows so here you can see the new path of the mains cold and hot water:

Copper pipes - gone!

The downstairs bathroom will need hot water again but it makes more sense to take it from the kitchen than following the old route.

Lagging

I've been a bit lax with lagging my pipes up until now but it's well worth doing.

For cold the benefits are: sound proofing (gushing water noises), reducing condensation (mostly a problem with copper), and keeping drinking water nice and chilled in summer.

The benefits for hot are soundproofing and heat retention.

For pipes outdoors lagging prevents them from freezing and it's a building regs rule that they need to be lagged.

To do this I used foam lagging which slips on and hugs the pipe. Very easy to cut with a utility knife.

Where you have pipes close to each other or a wall/joist you may not have the space for foam lagging but there's a product for that:

I'm not convinced the aluminium face does anything for pipes with hot water (may radiate heat away from cold pipes) so essentially it's just strips of bubble wrap. In another task I've done recently that's exactly what I used.

Works really well, with a little bit of aluminium tape to hold it 👍.

The soil stack

Last but not least is the big soil stack. This served the bath and sink in the old bathroom and also vents out the roof. This venting is important to allow smells out (also serves downstairs loo) and let air in to prevent 'back siphoning'. Imagine flushing a toilet and as the water shoots down the waste pipe there's no inlet of air. The air particles behind the water get stretched out away from one another so the pressure drops causing the water to shoot back up the pipe - probably out of your sink. Could be nasty!

So it needs an air intake but I need to get rid of the pipe and my new wall is too thin to fit a new one. Luckily there are air admittance valves, also known as durgo valves. The salient point is that air is only admitted one way - into the pipe. So the siphoning effect is nulled and no smells are emitted.

To add one I removed the shelving unit in the kitchen to reveal the service void.

I then cut out a section to access the soil stack. I cut the side out as well as this is not covered by the shelving unit so will allow air in.

I then cut the pipe and pushed on the AAV.

This particular one states in can be installed at any height but some need to be above the level of your highest exit - in my case the kitchen sink. It doesn't really matter for now so I installed it a bit higher for good measure.

At the the top end of the soil stack I figured there'd be a cap on it so I could just leave the rest of the pipe cut off in the loft. There was but it will certainly allow rain water in:

Can't have that. So I went top side and pulled out the remainder of the pipe from the roof.

Fortunately the previous owners left us with spare matching tiles so I slipped one in place. Luckily this was all easily accessed from the flat section of the roof.

I also had to move some aerial cables but probably not worth writing about. Here's the room with all the pipework gone.

So there you have it. Turns out Super Hans was right all along:

I jest, especially as I know there's at least one plumber who reads these emails ;). But wow, I've gone from not having a clue to doing all of this and have even tackled central heating pipes as you saw above. Feels great! Also it was the last major trade that I hadn't had a go at yet but now when I come across pipework in my DIY adventures, I don't have to stop and get someone in, which is brilliant. (Of course, this doesn't apply to gas pipes/boiler work)

For the more experienced of you, do let me know if you've spotted anything that's not quite right or could be improved. For the less experienced, hopefully this was encouraging 💪.

👋

I'll be back with another, shorter, newsletter soon. For now I'm off to watch the footy.

⚽ 🏴󠁧󠁢󠁥󠁮󠁧󠁿

Hit "reply" if you've got any comments on this week's newsletter – otherwise I'll see you next time. Have an epic week :)

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