Floor bounce - PosiJoist Floor Vibration checks

[Moonshine]

11 minutes ago, joe90 said:

A no brainier IMO.

 

The thing that worries me is the life span of the systems?

[joe90]

7 minutes ago, Moonshine said:

 

The thing that worries me is the life span of the systems?

I have come across leaking old copper pipes in the past, so nothing lasts forever. It was our own welsh wizard who converted me to hep20, he’s been using it for many years and swears by it.

[epsilonGreedy]

21 minutes ago, PeterW said:

 
Why..?? Hep20 is quicker and cheaper and needs less joins and is much easier to install. It also has less impact on flow and pressure reduction. 

 

15 minutes ago, joe90 said:

+1, I was a late convert but my new build is all hep20, no joins, all single runs with no restrictive 90’ bends, hot and cold manifold, dead easy. A no brainier IMO.

 

The only thing holding me back from selecting hep20 is:

 

[Iceverge]

22 minutes ago, joe90 said:

+1, I was a late convert but my new build is all hep20, no joins, all single runs with no restrictive 90’ bends, hot and cold manifold, dead easy. A no brainier IMO.

I should have done this in hindsight. Coupled with floor drains in all rooms with water connections in case of a leak. It'd be a very reasonably priced and future proof system. 

 

Our plumbers have used a crimp system which is €€€ and isn't easy to alter DIY. Also the Hep2o system being almost entirely plastic should mean no corrosion ever. 

 

 

@Adsibob

 

Have a play here to determine the deflections you could find acceptable. 

 

https://www.mitek.co.uk/span-calculator/

 

https://www.jamesjones.co.uk/products-and-services/engineered-timber/interactive-span-table

 

5 hours ago, PeterW said:

Ply at 18mm can’t be used on spans above 400mm as it isn’t rated for 600mm centres, neither is chipboard. For 600mm centres you would need to go to 22mm (which is hard to find in T&G Ply) so you need to compare like for like. 

 

On our garage it was cheaper to use 400mm centeres and 18mm decking over 600mm and 22mm. More solid too. Conventional 225mm joists though. 

[joe90]

1 minute ago, epsilonGreedy said:

The only thing holding me back from selecting hep20 is:

if your build is air tight, it should also be vermin proof?

[epsilonGreedy]

11 minutes ago, joe90 said:

if your build is air tight, it should also be vermin proof?

 

 

They have teeth plus endless patience to forage and explore!

 

I want to use hep20 but I also want to sleep at night.

Edited February 9, 2021 by epsilonGreedy

[Adsibob]

58 minutes ago, joe90 said:

+1, I was a late convert but my new build is all hep20, no joins, all single runs with no restrictive 90’ bends, hot and cold manifold, dead easy. A no brainier IMO.

Thanks @joe90 and @PeterW. I was told by a family member who has done a lot of property refurbs that plastic pipes are more prone to leak at the pushfit connections, and that whenever he has had to fix a leak it's been a plastic pipe. Now in those conversations, he definitely mentioned "plastic pipes" not "hep20". Is there a difference? 

 

I have no experience or knowledge of hep20, but I would have thought that if a mistake is made with the installation of a push-fit fitting on a hep20, it might not be noticed until the floor/ceiling is sealed up. i.e. on an initial test the loose connection just about survives and it is not until later that it fails, whereas with metal joins either its tight or its not and the plumber would see this immediately. Now this may all be just a figment of my imagination and as I say, i have little direct experience of either product.

 

My main concern is that I don't have the ability to supervise and check the plumber's work, so I rather specify what is most likely not to fail. But maybe that is hep20. 

[joe90]

I was recommended hep20 by our tame in house plumber on this forum ( @Nickfromwales) who has been using it for years and rates it higher than other makes. The golden rule though is to make sure the pipe, where it enters a joint, is not scratched as this could lead to a small leakage past the “o” ring. It also enables you to pull the pipe in like cable and only have joints at each end, no joints in places that cannot be accessible. Some people don’t realise how restrictive 90’ bends can be when using copper. Also hep20 uses thin stainless pipe inserts, not thick plastic ones like other manufacturers which restrict flow.  All plumbing should be tested before covering up, I have seen soldered copper joints hold water initially but fail afterwards.

Edited February 9, 2021 by joe90

[PeterW]

I’ve seen more failures on copper than Hep2O - fittings are bullet proof and have a rolling / rumble insert that guarantees they are in correctly. 

[Adsibob]

Okay, so Hep20 fittings and Hep20 plastic pipes seem to be clearly preferred on this forum. 
 

Two questions:

 

1) are they significantly cheaper than copper pipes and brass fittings?

 

2) does one still need to insulate the hot pipes?

 

 

[TonyT]

Copper for me?

 

but it depends on the install, so plant rooms , visible pipework all copper, anything that could be threaded through joists happy with Hep20 

plenty of full bore isolators to split install into smaller parts, for ease of installation, and isolating when something goes wrong

 

[joe90]

1 hour ago, Adsibob said:

Okay, so Hep20 fittings and Hep20 plastic pipes seem to be clearly preferred on this forum. 
 

Two questions:

 

1) are they significantly cheaper than copper pipes and brass fittings?

 

2) does one still need to insulate the hot pipes?

 

 

1) the fittings are more expensive but you need far less of the

2) yes

 

in addition, I ran 10mm hot feeds to basins to cut the cold slug and give hot water faster.

[Nickfromwales]

19 hours ago, TonyT said:

Copper for me?

 

Yup. In the plant rooms / exposed areas ( like one of my previous installs above ) I always change to something solid, but behind the scenes I run Hep everywhere else. The benefit of not having hidden joints in the fabric of the dwelling is good enough reason for me to mix the disciplines accordingly. 

[Adsibob]

3 hours ago, Nickfromwales said:

The benefit of not having hidden joints in the fabric of the dwelling is good enough reason for me to mix the disciplines accordingly. 

So if I were to do that, how does the join from a Hep20 pipe to an outlet, say a tap in the bathroom or kitchen sink, not get “hidden” and at the same time not be visible whilst one is actually using the tap. Is it concealed within a basin cabinet? What about with a shower or bath tub? Apologies, I’m a complete novice.

[Nickfromwales]

33 minutes ago, Adsibob said:

So if I were to do that, how does the join from a Hep20 pipe to an outlet, say a tap in the bathroom or kitchen sink, not get “hidden” and at the same time not be visible whilst one is actually using the tap. Is it concealed within a basin cabinet? What about with a shower or bath tub? Apologies, I’m a complete novice.

Once the uninterrupted Hep has traversed the entire build from A to B then there are joints to covert the Hep to copper / brass. It is accepted as you’d have the same connections if going from copper to brass, just this introduces just one more joint. You can get Hep to brass in a single fitting, so check out the full range at Hep (Link ) website to see what they offer to get you up and running. Hep also do flexi tap connectors to go from Hep to 1/2” and 3/4” taps in one item.

For clarity, a lot of folk on here are installing radial plumbing runs to each outlet so no T connections are required  ‘behind the scenes’. If you want to do series ( regular ) plumbing then you will likely end up with some additional joints. 

 

[Adsibob]

12 minutes ago, Nickfromwales said:

a lot of folk on here are installing radial plumbing runs to each outlet so no T connections are required  ‘behind the scenes’. If you want to do series ( regular ) plumbing then you will likely end up with some additional joints.

thanks @Nickfromwales that’s helpful. Re your point above, what are the advantages and disadvantages of radial pipes over regular series, apart from being able to switch off individual supplies with radial? Does radial require a manifold and aren’t these quite pricy?

 

 

 

[Nickfromwales]

37 minutes ago, Adsibob said:

thanks @Nickfromwales that’s helpful. Re your point above, what are the advantages and disadvantages of radial pipes over regular series, apart from being able to switch off individual supplies with radial? Does radial require a manifold and aren’t these quite pricy?

In a one bathroom house it would be difficult to make it add up, and at that stage you’d consider not steering away from the vernacular.

Manifolds can be cheap ( DIY ) with these or a few £ with Hep2o brass ones ( my weapon of choice ). Ultimately they’re not going to be turned off very often. 
Main advantages are maintaining pressure ( flow ) to multiple outlets simultaneously, but only a notable benefit if there are a at least a couple of bathrooms that you’d want to be showering in at the same time. How good your cold mains is and the max flow rate of the hot water device will dictate what can be delivered of course. If you’ve a combi, for eg, then little point in radial plumbing of course. 

[pdf27]

5 hours ago, Nickfromwales said:

Yup. In the plant rooms / exposed areas ( like one of my previous installs above ) I always change to something solid, but behind the scenes I run Hep everywhere else. The benefit of not having hidden joints in the fabric of the dwelling is good enough reason for me to mix the disciplines accordingly. 

What's the benefit of copper in these areas - is it just aesthetics, or is there some functional benefit?

[Nickfromwales]

Just now, pdf27 said:

What's the benefit of copper in these areas - is it just aesthetics, or is there some functional benefit?

Just all the controls / valves etc need something ‘fixed’ and copper / brass offers that. Push-fit also tends to allow the pipe to rotate ( deadly with JG Speedfit as it can simply undo itself. 
I try to do all my plant rooms with copper and a mix of soldered and strategic compression joints, eg to allow a ‘spanner only’ removal of any and all valves etc, ( so no cutting and soldering to replace anything U/S is the end goal ). @PeterStarck’s install with JG remains a thing of beauty, but a labour of love. 

[TonyT]

Connecting copper direct to boilers isn’t a problem, it is for plastic

 

in the event of fire, plastic melts, copper doesn’t 

 

copper has antimicrobial properties.

 

copper is generally going to be easy to alter in the future, where as plastic fittings may be specific and become obsolete.

 

Copper doesn’t sag and looks better with brass stand-off clips.

 

first impressions copper looks proper in a plant room, plastic looks like a builders been at the plumbing.

 

 

 

[Nickfromwales]

7 minutes ago, TonyT said:

Connecting copper direct to boilers isn’t a problem, it is for plastic

Most if not every boiler manufacturer stated not to connect push fit within 800-1000mm of the boiler. 
 

8 minutes ago, TonyT said:

in the event of fire, plastic melts, copper doesn’t 

So you get a free sprinkler system  

 

9 minutes ago, TonyT said:

copper has antimicrobial properties.

Not really a problem in a modern sealed system. 

 

10 minutes ago, TonyT said:

copper is generally going to be easy to alter in the future, where as plastic fittings may be specific and become obsolete.

Only a problem really if you go for a lesser known manufacturer. Copper is on its way out, so the market lead will end up plastic / other synthetic in the long run. 
 

12 minutes ago, TonyT said:

Copper doesn’t sag and looks better with brass stand-off clips

Pipe clip centres need to be observed, but agree where on show, or where repeated light impacts may occur, copper is best.

 

13 minutes ago, TonyT said:

first impressions copper looks proper in a plant room, plastic looks like a builders been at the plumbing.

Lol. Agree 100%. 

[Adsibob]

23 minutes ago, Nickfromwales said:

In a one bathroom house it would be difficult to make it add up, and at that stage you’d consider not steering away from the vernacular.

Manifolds can be cheap ( DIY ) with these or a few £ with Hep2o brass ones ( my weapon of choice ). Ultimately they’re not going to be turned off very often. 
Main advantages are maintaining pressure ( flow ) to multiple outlets simultaneously, but only a notable benefit if there are a at least a couple of bathrooms that you’d want to be showering in at the same time. How good your cold mains is and the max flow rate of the hot water device will dictate what can be delivered of course. If you’ve a combi, for eg, then little point in radial plumbing of course. 

Once it's finished, my house will have three bathrooms, a kitchen sink, a utility room sink and a sink for the guest WC. So plenty of outlets. We're a large family so chances of more than one person showering and also having to compete with the person doing the washing up in the kitchen sink are fairly likely. But I had thought that one could maintain pressure/flow (these are different albeit related concepts of course) by installing an unvented hot water cylinder. Isn't that the main advantage of an unvented hot water cylinder over say a combi boiler, in that a cylinder will replicate mains pressure at flow across multiple outlets? Or have I completely misunderstood that?

 

I haven't managed to figure out my mains pressure/flow yet because I know it is currently poor, but we are upgrading the diameter of the connection to the water company's mains, so once I do that I will know for certain. But prior to the upgrade I think I was only getting about 13 or 14 litres a minute and probably a bit less during peak times. Fine for a single shower, but unusable when I was in the shower competing with the kitchen sink (though I guess that could be down to the boiler we had which was a 18kw Vaillant ecotec from about 8 years ago. Also interesting that with that boiler if you switched the heating on at the same time as trying to have a shower, the heating wouldn't come on until the shower was turned off. So useless for heating up a towel on a towel rad whilst having a shower.

[Nickfromwales]

The bottom line is, the UVC is cold mains dependant, so hot water flow would reduce if even just the washing machine was filling. 
Ive installed a number of cold mains accumulators in dwellings where I expected this to be overly problematic, to combat this very issue. If you’ve not hit a very good cold mains then perhaps you may want to consider inclusion of one of those to bolster the cold mains supply, post stopcock. 

[Adsibob]

12 hours ago, Nickfromwales said:

The bottom line is, the UVC is cold mains dependant, so hot water flow would reduce if even just the washing machine was filling. 
Ive installed a number of cold mains accumulators in dwellings where I expected this to be overly problematic, to combat this very issue. If you’ve not hit a very good cold mains then perhaps you may want to consider inclusion of one of those to bolster the cold mains supply, post stopcock. 

Thanks @Nickfromwales. What calculation do I need to do to know what size accumulator to go for and are there any particular brands and models you recommend?

[Nickfromwales]

2 hours ago, Adsibob said:

Thanks @Nickfromwales. What calculation do I need to do to know what size accumulator to go for and are there any particular brands and models you recommend?

Static mains pressure needs taking over 24 hours. Put a non return valve on the pressure gauge so the peak value is preserved. Then the dynamic flow rate in L/p/m with the outside tap for eg open fully. 

Zimlet via Anchor Pumps Ltd are robust and competitively priced. 2-300L is pretty much every level for a domestic dwelling as these only hold 50% or less of their volume as usable energy.