Hi! I just bought a subsale landed property and will kick start renovation soon.
Since the house is more than 10 years, I am considering to replace the piping for whole house so that can get a peace of mind without worrying water leakage after move in.
Had plenty of reading but still not really have a good idea which type of pipe to go with.

1. For those conceal in wall, which type is better as the hacking in future will be really costly.

2. Is there any idea to hide the piping if not conceal to wall?

3. Which type of piping is commonly used in the market now? PVC or HDPW Poly or Stainless Steel?

4. Understand that still some possibly of corrosion/rust for copper and stainless steel after long period of usage. Is it true?

5. Any idea on the costing for PVC or HDPE Poly or Stainless Steel?

Your valuable comments and experiences are very much appreciated!
Thanks in advance!

From the main, route it through the ceiling to reach the reserved tank and down towards the kitchen, laundry or gr fl bathroom. As for other areas, route from the reserved tank.

Always have a photo shot for all conceal piping routing so you know where to hack when any leakages happen.

Piping is either conceal or expose. No other method.

Have spare tiles for replacement if hacking is needed in the future. You wont find the similar tiles 5 years later.

As for piping material, up to your budget. Quality equal to cost.

To reduce sediment build up in reserve tank or piping line have a filter after the main.

Edit ...

Add another reserve tank for future water rationing .

Have a piping routing from the reserve tank to the kitchen sink to have water flow during water rationing.

I did both for my house.

This post has been edited by mini orchard: Nov 2 2020, 07:39 PM

A.Separate WC flush from bath/shower and basin.
These need not be pump powered. The piping should be 1-1.25"" in the ceiling then reduced to 3/4" in the wall..it should exit as 0.5" fairly high up..18"-24" from the floor next to the WC and have no horizontal runs. In this manner it won't crisscross piping for bath/shower.

This is doable for upper bathrooms but not as easily downstairs bath/toilet depending on where the WC is located.

B. Isolate piping downstairs bathroom/ toilet from upstairs bath
Esp if upstairs is a pumped circuit which should only reserved from for upper bathrooms.

Otherwise, a leaky toilet valve esp downstairs will cause the pump to dry up the tangki very fast. Plus not to mention the heat stress of a dry pump.

C. Employ isolation valves at every outlet
WM (it's bib is the isolation valve), kitchen sink tap, WC refill and bathroom basin taps to ease maintenance. With this flow rate can be hard adjusted to prevent using more water than necessary, giving priority for outlets that need it.

It also deals with leaks esp WC flush valve such that until the valve is fixed, it can be isolated. At the mean time a 5 gallon pail with a scoop stands as backup duty for toilet flushing.

With the recurring water interruption seen this year, all this should help minimise and plug unwanted wastages due to wear and tear.

Also, ozak's advice on how to autobackup from tangki helps if you are going the traditional piping route from meter to the back of the house from front to back and up into tangki.

You might need to adjust if routing from meter up the front of the roof to tangki then down the back to kitchen and laundry. That's what my old neighbour did because they didn't want to hack their marble floor just to re-lay new pipes as replacement over the aged piping.

This post has been edited by halcyon27: Nov 2 2020, 06:37 PM

Thanks for sharing and the idea for adding another reserve tank is really good.
I'm thinking to add one reserve tank on top of my extend kitchen roof top.
Perhaps a little higher cost to build up the reinforced concrete roof for my kitchen extension.

You wont regret with the additional cost.

FYI, the water can be real hot during the day....but better than no water. Mine is under a shade as I have a covered space for the tank.

This post has been edited by mini orchard: Nov 3 2020, 08:54 AM

water pump ur system... my water flow is very weak from the tank above (fill up my masterroom toilet need 20minutes, omg).. so sad... and the tank is not accessible from inside the house, have to climb from outside... not dare do that myself.

Since no one is answering your question, then I'd say use HDPE. If there is stress in the wall like crack due to land sink, the PVC will crack. I've never hear heard people use stainless steel in wall but usually the steel is not thick enough to prevent rupture due to deformation perhaps in severe stress. Stainless steel on surface maybe, but not in wall.

Thanks @halcyon27 for the useful advices.
Any idea on which type of water pipe is recommended for:-
1. Main to reserve tank (concealed)
2. Main to reserve tank (exposed)
3. Reserve tank to WC & Kitchen (concealed)
4. Reserve tank to WC & Kitchen (exposed)

20 minutes? If you are using floating ball type to fill the flush tank, then it is because the rubber stop is stuck already. Use the other type that let water run max flw and just clicked to stop when full. The float ball type will make water flow slower and slower when approaching set level.

Yeap, I broken the wall faucet last month, now redo the whole piping for the toilet...
the original piping issue that causes the slow flow... didnt know until the hacking to show me how many 90 degree angle the developer used... OMG! headache...

on the pump... since my original piping is so fail... the pump make up the difference between wait 20 minutes and syok feeling shower...

Hi @Zot! Thanks for your good reply.
If I'm not mistaken, HDPE can last longer if not expose to sunlight/UV, also it is having more flexibility, right?

Any idea on which type of water pipe is recommended for:-
1. Main to reserve tank (concealed)
2. Main to reserve tank (exposed)
3. Reserve tank to WC & Kitchen (concealed)
4. Reserve tank to WC & Kitchen (exposed)

I would like to get a peace of mind without water leakage after move in. Hence, need your advices with your past experiences.
Thanks!

as for the material, based on my reading since I'm not engineer, you can use PVC. but pls be careful since there are many classes. can opt for class 7 which is quite thick.

My whole house water filter was in front and now I relocated it at the back of the house. Yes, I use poly pipe (so called HDPE).

For my house the developer is suing that blue pipe (I think ABS). This is more rigid than PVC but like PVC it is not for exposure to sunlight. The HDPE itself is easily weakened by UV, but the material is mixed with UV resistant material when produced. The nature color of HDPE is quite clear but the UV resistant material that makes it black in color. Yes, it can withstand outdoor. My developer is using this pipe underground from meter and up to roof before joining with ABS to the tank.

If you watch house renovation program in Astro, in the US the red and color pipes are PEX which is popular. Here I think still new and more expensive. That is also for indoor. At kitchen extension in my house the plumber use PB pipe (Polybutylene). You can know this because they usually use crimping to join. I was worried about leaking but the plumber said no problem. The PB pipe is very flexible and it is more than 12 years now with no problem.

This post has been edited by Zot: Nov 3 2020, 09:36 AM

There other reasons why piping are concealed other than for esthetic purpose.

The cement plastering holds the pipe firmly compare to those exposed during water flow. Normally those leaking pipes are around the reserve tank area where are exposed and not firmly held. Concealed seldom leaks unless there is ground movement or poor workmanship at joins.

In addition, is not easy to attached faucets tightly to exposed piping line. High water pressure from main or pumps will create vibrations and leaking will eventually happen at joins which should not happen if is concealed.

As advise earlier, have photos taken during construction so you know where to troubleshoot if there is a leak.

This post has been edited by mini orchard: Nov 3 2020, 10:13 AM

Thanks for the sharing! Will adopt poly pipe instead since it is affordable and common in market

Very much appreciated on the good info!
Any idea on the cost to replace the whole house piping to poly pipe for 2.5 storey house with 4 bathrooms?

I wont know ... you need to have few quotes.

I suggest you have a main contractor to coordinate instead of piece meal contractor.

Plumber wont do replastering and fixing tiles....they only know how to break. The main con price will definite be higher.

This post has been edited by mini orchard: Nov 4 2020, 10:01 AM

Thanks for the reply.
For the reserve stainless steel water tank, do we need additional reinforcement on the concrete roof if I am to place it on top of my extended kitchen?
Or just the standard concrete roof will do?
Normally which capacity that normally people will go for 2.5 storey landed house with 4 bathrooms?
Thanks!

If is oredi concrete slab, not necessary.

For capacity, go for the biggest litres your roof can support. Buy 1 large or 2 smaller capacity. I have seen some having 3. 1 time work during reno if have the budget. Check with the contractor.

More reserve better than no water.