MortarThePoint

Thanks. Classic example of the difference between (book) knowledge and experience. I would have walked straight into that one.

Is that one of those things where the brochure says you can but experience says you can't?

I still don't know why the transition to copper. It seems to be common practice (see below) but I'm in the dark ( @Nickfromwales )?

Looks sturdy, but won't that need to be installed prior to the plasterboard that it goes through? Or do you attach it to a pattress and then mount the pattress on the studs.

Why the transition to copper? Thanks for the link, exactly what I'm after.

Another hopefully simple question for you. Do you just use pipe and a couple of elbows (all Hep2O) to prepare for a 150mm pipe spacing shower bar mounted on a plasterboard wall (with OSB layer behind the plasterboard)? I've got my OSB and plasterboard wall up and want to poke the pipes through and seal up the wall. I as planning to just use a couple of Hep2O elbows and pipe to do this. Is that how you do it? I'd then use the Easy-Fix style of connector with its included olive to attach to the Hep2O pipe.

A fair call. I find I only have two tools to compensate for my inexperience, asking and researching/analysing. Asking is much preferred but I feel a bit guilty asking so many questions sometimes.

The detail below is a solution except I am using resilient bar to separate the ceiling plasterboard from the joists so I need to bridge that gap. The noggin would normally do this but that world short circuit my resilient bar. I'm not really sure why in that detail it's a double noggin.

Is it a viable solution to create two separate airtight 'cells'? One above the joists and one below? The air in the height of the joist would not be sealed. That shouldn't be a problem from a thermal perspective as there is insulation at the ends and the two 'cells' would be airtight so not transferring moist air to this space. This is the easiest approach, but is it valid?

Interesting. I've always been impressed by the Napoleonic era triangulations. Curvature of the earth would render a laser level 3mm out at 200m I think. Unless the world is flat of course 🙂

Interesting, that webpage is a bit light on how it works but is the 'wire' connecting the two units actually a tube full of a liquid and it measures the pressure difference between the two sealed ends? Very handy it doesn't need line of sight.

is rather poor. I'm not timber frame person, but +/-2.2mm over 30m doesn't sound poor to me. That means one end of a 15m house might be 2mm lower than the other. What needs to be better than that?

I hope so, thanks 🙂 I'm going to need to invest in a pressure testing pump as I need to high pressure test at something like 10bar.

@Conorthe pictures you shared are a very useful reference. You've got a mixture of two ceiling systems, GypCeiling Lining (using GL1 Gyplyner and GL2 or similar brackets) and GypCeiling MF (using MF7 Primary channel and MF5 top hat). The former allows a shallower void (down to 25mm) as the height of just the MF7 and MF5 is 70mm so the minimum void with that is likely to be 100mm. My plasterer is nervous about the GypCeiling Lining being flat enough. I had hoped to do something that could be adjusted using packers but MF systems would be harder to do that with that timber battens I think. The GypCeiling MF's primary channel is nice and stiff and the fixings are 1200mm x 1200mm rather than 1200mm x 400mm so any 'gradients' will be less with GypCeiling MF. I've bought a house load of GypCeiling Liner though so I'm going to have to experiment I think. Any tips gratefully received.

I've more lasers than make sense to be honest (no sharks with lasers on their heads though). I bought a cheap rotary laser from China (see red one below, £175 at the time) but I wouldn't recommend it as it had an issue straight out of the box. I was able to fix it and have tested it's accurate. Like with a spirit level, it is important to know how to regularly check this sort of device as you don't want to find out later that there is a problem. When I have done surveying I have repeated the process twice with the rotary laser in two different places and checked that the sets of readings agree. As I am a massive geek, I have also used homebrew RTK-GPS for surveying which works nicely for plan, but not so well for elevation. There are various non-rotary 3D lasers that have a pulsing feature. The pulsing allows you to use it with a detector when light levels and distance are too great to see it by eye. I've never used the glasses which could help under that situation. I have a Huepar one which supports the pulsing. I've never used that feature, but at dusk or in the dark it throws the laser a very long way. I thought this laser was good enough to by a second one when I smashed the first falling off a ladder. I got it from Amazon for £160 but it's now £145 (https://amzn.to/3mSTxaV note that's an affiliate link but doesn't cost you more).

You're right, I'm just trying to avoid newbie mistakes 🙂

Placing the pipes between two layers of 25mm APR. I wanted 15mm pipe sticking out of the wall to attach the basin flexis to so used a 15mm/10mm reducer and 15mm elbow. Where I'm going to box out near the floor I was able to send the 10mm pipe through at a slight angle to allow it to fit in the 70mm cavity. I pushed the Hep2O fittings together really hard, but the In4Sure rumble was very hard to feel except for the reducer. I couldn't rotate the last elbows either as they had to be assembled once already through the wall. I don't want to disassemble it and reassemble in a different order that allows turning. How important is that?

Clearer units:

He's a rough table using the Pegler equation but Hep2o ID dimensions: [Note: 1bar across 20m is 0.5bar across 10m] So at 10m and using 15mm pipe it would take about 2 minutes to put 100 litres of 2:1 water in a bath if 3bar dynamic pressure was available. It would take 4minutes if the dynamic pressure was only 1bar.

For shaving, so assuming pure hot water, it would be good to fill the basin in under 1 minute. Assuming the water in the basin basin is 300mm x 300mm x 100mm that equates to 9l, so the desired flow rate is 9l/60s = 0.15l/s. That's OK for 15mm pipe up to around 20m with 1bar loss. 10mm pipe and 1bar@20m yields a flow of something like 0.06l/s (or 2.5min to fill basin). Using their head loss tables, gives a pressure drop of 5.4bar over 20m at 0.15l/s for 10mm pipe. For shaving, a 10mm pipe run is probably limited to 10m if a dynamic pressure of 3bar is available. If only 1bar, you'd fill a square foot basin to 2 inches (shallow but can start shaving, 4.5l) in 1 minute at 10m (it's very non-linear remember). For hand washing a flow of 3l/min = 0.05l/s is probably acceptable and it's not pure hot. If it was all through one pipe for 20m I estimate a pressure drop of 0.8bar which is fine to be under 1bar including the tap loss. If you have an en-suite, a family bathroom basin would be ok at 20m with 10mm hot feed until a son started shaving.

Based on the Domestic nomograph, a shower at 20m equivalent run, 1bar pressure and assuming 1m head loss across the shower taps/head with a flow rate up to about 0.2l/s or 12l/min. That's along the orange line of the first Hot image above.

How to size Hep2o pipe (check out pages 60-62 of https://www.hep2o.com.au/downloads/Hep2o_Parts_Users_Guide_Australia_2018.pdf) Image below if for COLD supply. As I understand it, you work out you acceptable pressure loss in metres per 100 metres (which is the same as mbar/m) and then draw a straight line through the required flow rate and that hits the pipe size scale and so you pick the next number up. The dashed line is an example of 14.9m / 100m head loss with required flow of 0.3l/s giving 22mm pipe needed. 0.3l/s would provide 90l of bath water 5 minutes, but of pure cold. My most extreme situation will be around 0.3l/s over 15m, but I'll round that up to 20m to cover elbows / isolators. They (page 60) assume 0.8m head loss across the tap, I'll round that up to 1m (so 0.1bar). If I'm happy with 1bar pressure loss then: Head Loss = 0.9bar / 20m = 45mbar/m = 45m / 100m Using the cold water nomogram shows 22mm is needed for that. 15mm would be OK up to around 0.17l/s. There is a domestic hot water nomogram as well, but I suspect that just assumes something like the flow is 67% hot and 33% cold. With 65C hot water and 12C cold water that would make for an average of 30C. To use that and use 15mm pipe I would have to accept a head loss of 80m / 100m which equates to 1.6bar over 20m. Round that up to 2bar. My mains is 5.5bar at no flow, but I don't know what that would drop to at 0.3l/s. Cold: Hot:

OK so that calculator is guff. I've got headloss data for Hep2o and at 6l/m the headloss is 1.5bar/10m for 10mm pipe, 0.14bar/10m for 15mm pipe and 0.016bar/10m for 22mm pipe. I've checked this against another source (Pegler pip, OK not plastic but fine) and it roughly tallies. Flipping to work out what flow rate creates a 1bar pressure loss over 10m: 10mm 0.08kg/s 5l/min (est) 15mm 0.31kg/s 19l/min 22mm 1.07kg/s 64l/min

Almost ready to cover up with APR and plasterboard. I used Kilmat as @Nickfromwales suggested to help with any noise. The clips are 40mm clips used on 32mm pipe with foam tape wrapped around to reduce noise transfer. The pipe exits the wall within a 100mm square from the floor and the wall. At the other end you can see the pipe exit at around 500mm from the floor and with H and C written just above where I am going to send the water feeds through. I think those holes are 60mm higher than the waste hole and 80mm apart. The plan is for the feeds to then split inside the room to feed the two basins as that puts fewer fittings in the wall. I'll need to use elbows on the feed pipes as the wall cavity is only 70mm and the bend radius is 120mm/80mm for 15mm/10mm pipe. I could exit the wall at an angle but I think that could look bad.

A 10m run of 22mm pipe has a dead volume of about 2.5litres so a 10l/min shower would take 15seconds to heat up, presuming the thermostatic valve runs pure 'hot' until actually hot water arrives. 23 seconds for 15m. It's a waste if water, but not too much time. It feels like under 10s is awesome, under 20s, desirable and under 30s acceptable. I've no idea what an pleasant shower flow rate is, but have read figures like 12l/min down to 6l/min for Part G. According to this calculator, 15m of 15mm OD 11mm ID pipe needs 3bar pressure to supply 5l/min which if the shower is running at 50/50 is at total 10l/min. A 22mm OD 17.7mm ID pipe needs under 0.2bar. Can anyone report good results having run over 15m of 15mm pipe to a shower?