Cutting Concrete

[chiangrai]

I have to put in a 1 inch PVC pipe from my water tank to my shower.

I have to cut concrete twice to do so.

First the tank which is made out of large concrete rings.I have to make a hole in it

and put in a PVC pipe with a tap on it.

How do I make the hole.I will try with a concrete drill bits and a chisel if no body has a better idea.I have a 4" angle grinder if that would help.

But more importantly how do I fill in the hole once the pipe is in.

What do I fill it with and how do I stop the filler falling into the inside of the tank.

Then I need to cut a channel across the concrete yard to get to the bathroom.

It's only about 3 feet long without any bends but I have no idea how to go about it.

If I use the 4" angle grinder it will not go deep enough to bury a 1" pipe.

I have a circular saw(7.25") but no diamond blade for it.

I see them costing 2500bht on eBay and don't want to spend that much.

Any ideas

[Crossy]

A diamond hole-saw will cut the tank. You should be able to cut a hole the right size for the fitting.

A diamond blade for the circular saw will slot the concrete, chip out the waste.

If you don't want to buy, find a man who has same

OR

Assuming you are going to use a pump then you could drop the suction over the top of the tank down to near the bottom. No need to cut the tank, no potential for leaks.

Run the pipe on top of the concrete Thai style, maybe build a little 'speed bump' over the pipe to protect it from traffic.

[Mooner]

What Crossy said with the pipe.

In regards to the going across the yard. A 4 inch grinder will cut 2 inches into the ground. Cut where the pipe will then break out with a hammer and bolster then cut the trench again and repeat.

In all honesty the concrete is probably only about 4 inches deep anyway.

[chiangrai]

"A diamond hole-saw will cut the tank. You should be able to cut a hole the right size for the fitting"

I've got how to cross the yard with the angle grinder but I'm still not sure about

the tank.

It's a gravity flow tank so I'm not using a pump."A diamond hole-saw" is that a power tool or an attachment.anyway I don't have one.I am really remote here so there is no popping into HomePro or borrowing from friends.I have to order off eBay and wait.What size would I get to be the same as the outside measurement of a 1" PVC pipe.

[Crossy]

I strongly recommend you find a local man-who-can.

You'll need threaded tank fittings / nuts so they don't blow out under the water pressure.

Who built the tank, did they not include a means of tapping off the contents?

EDIT Do you have access to the inside of the tank? If not it's going to be very difficult to secure a pipe

[bankruatsteve]

Suggest you consider buying a proper water tank: stainless steel the best but also most expensive but almost any of them would be better in the long run than concrete. As for cutting concrete, the above suggestions probably best but just to say I have used the hand held thingy that just about every Thai worker has and can mount blades, brushes, etc. Anyway, I put a "concrete cutting blade" (pretty sure no diamonds) on that and it happily cut into my sidewalk for a similar purpose.

[chiangrai]

The guys that put in the tank smashed a hole in it ,put in a half inch pipe an filled the hole up

with concrete.

There is not enough pressure with the half inch pipe so I want to put in two 1" pipes.

I presumed that I would do it the same way they did.They seem to have filled the hole up with a fine mix of cement like a render mix or something.If I knew what that was could probably do it.

[inzman]

If you don't have enough pressure with the existing pipe. You won't have any more with a bigger pipe, just volume. Buy a pump.

[bankruatsteve]

What's the elevation of the tank to your shower? As Inzman said, you could put in a 4" pipe - the pressure will not increase (actually probably decrease). For that purpose, you can find a pressure pump for B1500 or so from the local store that will give you a good shower and just keep what you already have.

Edited March 30, 2016 by bankruatsteve

[canuckamuck]

I have put quite a few holes in cement rings and added pipes to them. I don't have a hole saw. I just drill a circle pattern of holes slightly larger than the pipe going in. Then I slowly tap a way with a hammer to get out the center part. Smack it too hard and you crack it. Chisel off the bits that remain in the way. Then I insert the pipe, fill both sides with a standard concrete mix. I add a water proofer compound if I have it. Wait a day and there you go. It may drip for a day or two and then it will stop on it's own due to calcification

Lots of cement bits go in the tank, but usually I have a way to clean it up a bit before it is used. It's just concrete so no harm anyway.

[chiangrai]

Even if the larger pipe doesn't increase the pressure(which some say it does) I will be dividing

the load between 3 pipes so nothing will be in parallel,that will surely increase the pressure.

Canuckamuck,what is a waterproof-er compound.Otherwise you seem to have the same idea as me.

[canuckamuck]

There is an additive you can buy in most of the local chung shops. it is supposed to help the concrete become more water proof. I think they call it Gun Nam. It's hardly worth it for the little bit you'll be doing though. Those rings self heal after a few days usually, and so does the concrete patch.

[chiangrai]

Thanks Mate,that's me sorted.

[Daffy D]

Wot "canuckamuck" says will work just fine.

Depending on your set up a bracket to hold the pipe where it comes out of the tank would be a good idea to stop any accidental pipe movement breaking the joint between tank and pipe.

A waterproof-er mix in with the cement hole filler is not really necessary, after all the concrete rings aren't waterproofed , but if it makes you feel better those kind of additives can be found at any building suppliers including the big stores like Home Mart and Thai Wasadu.

[bankruatsteve]

Even if the larger pipe doesn't increase the pressure(which some say it does) I will be dividing

the load between 3 pipes so nothing will be in parallel,that will surely increase the pressure.

Canuckamuck,what is a waterproof-er compound.Otherwise you seem to have the same idea as me.

"Dividing the load between 3 pipes" sounds like parallel to me. Whatever. The ONLY thing that will give you more pressure is height (from your tank to point of use) or a pump. The size of pipe will do nothing for pressure.

[wayned]

Cutting the channel across the concrete slab might be a little harder than everybody makes it out to be. Sure, the diamond saw will cut the concrete whether in an angle grinder or circular saw, but what about the iron rebar or wire mesh that's in the concrete. It will quickly destroy your diamond blade.

[Daffy D]

Cutting the channel across the concrete slab might be a little harder than everybody makes it out to be. Sure, the diamond saw will cut the concrete whether in an angle grinder or circular saw, but what about the iron rebar or wire mesh that's in the concrete. It will quickly destroy your diamond blade.

IF there is any re-bar change to a metal cutting disk. Or chip the concrete round it and lay the pipe underneath.

Getting back to the pipe to tank.

If you can get inside the tank or maybe use a bit of ingenuity with wire and string, connect and reverse a pipe reducer from the 1" pipe to say 2" or 3" onto the end of the pipe that's inside the tank and fill it with concrete as you fit it to stop any possibility of the pipe popping out for any reason.

[Mooner]

Cutting the channel across the concrete slab might be a little harder than everybody makes it out to be. Sure, the diamond saw will cut the concrete whether in an angle grinder or circular saw, but what about the iron rebar or wire mesh that's in the concrete. It will quickly destroy your diamond blade

If there is it will likely be the 3 or 4 mm stuff. I ve cut metal loads of times with a diamond blade and they still work ( not ideal i know) No big deal, go buy another one.

Also they tend to put the steel at the bottom so shouldnt be an isssue.

[sometimewoodworker]

Even if the larger pipe doesn't increase the pressure(which some say it does) I will be dividing

the load between 3 pipes so nothing will be in parallel,that will surely increase the pressure.

Canuckamuck,what is a waterproof-er compound.Otherwise you seem to have the same idea as me.

Anyone who tells you that a larger pipe will increase the pressure doesn't understand basic physics, as has been mentioned, the only way to increase pressure, apart from a pump, is to increase the height of the container. The pressure will increase by 1.45 psi for each metre of added hight.

A larger pipe will permit greater flow at the same pressure, it makes no difference if the pipe is 50mm or 500mm.

[ThaiKneeTim]

There is an additive you can buy in most of the local chung shops. it is supposed to help the concrete become more water proof. I think they call it Gun Nam. It's hardly worth it for the little bit you'll be doing though. Those rings self heal after a few days usually, and so does the concrete patch.

A cheap, and easy to obtain, alternative to a proprietary waterproof additive is latex. Mix with water then use the mixture to make your cement up.

Latex mixed with water is also good for use as a showerproof sealant on absorbent surfaces like concrete or natural stonework. It's also good for preparing absorbent surfaces ready for plastering.

[chiangrai]

Here are some quotes from a previous post I had...

"As others say, up sizing your pipes is a good idea. Less pipe friction means you'll get more flow and also can run more than one tap in parallel"

"f you can keep all the pipe in large bore pipe all the way to the water heater you will have better pressure."

"Any length of small bore will reduce the pressure, the longer the run the lower the pressure. Also all sharp 90 degree bends reduce the pressure".

So weather up sizing the pipe increases the pressure or the flow it will still improve the likely hood of the

shower having enough water to run the shower...............right?.

I am bringing the 1" pipe all the way to the shower.

[canuckamuck]

What increases is the friction, the pressure stays the same. So no matter what you do you will get the same pressure, but the flow will be reduced (friction increased) by: Bends and angles, narrow pipes, distance.

[Crossy]

All of the above will improve the available pressure at the shower (by reducing the losses in the pipe). None, not a one, will increase the maximum pressure available, that is the static head determined by the height of your water tank above the shower head.

To be honest, a cheap pump will increase the available pressure by an order of magnitude and be considerably less work than running a new pipe.

One of these https://www.directtoshop.com/product/245249 would do a fine job, just add a few pipe fittings to adapt to the existing pipe and a suitable power supply and you're good to go.

[ThaiKneeTim]

If flow is restricted it will result in pressure loss, but the restriction would have to be pretty severe, like a crushed pipe, a stone or something blocking the pipe, or a partially closed valve. I would be checking the pipe for instructions before contemplating changing the pipe. It may be that you only need to unblock, splice in a new section of pipe, or replace a dodgy valve.

If you can, measure the top water level of the tank and the shower head to determine how much pressure you should have, and if possible measure the pressure you actually have at the shower head.

You could go to a great deal of trouble to install a new pipe and still not have enough pressure, now that would be a real pisser!

[Crossy]

You could go to a great deal of trouble to install a new pipe and still not have enough pressure, now that would be a real pisser!

More of a dribbler

Seriously to our OP :- Roughly how far above the shower head is the tank mid-point water level? You need a much greater height for a gravity fed shower (particularly if you have a water heater) than many people think.

[Daffy D]

I built a water tower with a 2000lt tank on top that gave a total 6mt head of water.

This just gave adequate pressure to the taps but hopeless for the heated shower still had to get a pump for that

Edited April 1, 2016 by Daffy D

[chiangrai]

The tank is only about 20ft above the shower and 30 meters away.

At the moment there is 1 half inch pipe coming out of it,doing the hole house and

the shower has nearly enough power to run the shower.If you hold the shower head at waist height it runs fine,if you hold it above your head the gas cuts out.I'm assuming that this is a safety feature that cuts out when the flow of water is so low that the machine will overheat.

The point is that it only needs a tiny bit more water going through it and I am doing 3 things to improve it.

!-Giving the shower it's own pipe from the tank

2--doubling the size of that pipe.

3--making sure that the new pipe has only one right angled bend in it as the present one has many.

I reckon that should do it.If not,there is nothing else I can do save install a pump or raise the tower.

[bankruatsteve]

The tank is only about 20ft above the shower and 30 meters away.

At the moment there is 1 half inch pipe coming out of it,doing the hole house and

the shower has nearly enough power to run the shower.If you hold the shower head at waist height it runs fine,if you hold it above your head the gas cuts out.I'm assuming that this is a safety feature that cuts out when the flow of water is so low that the machine will overheat.

The point is that it only needs a tiny bit more water going through it and I am doing 3 things to improve it.

!-Giving the shower it's own pipe from the tank

2--doubling the size of that pipe.

3--making sure that the new pipe has only one right angled bend in it as the present one has many.

I reckon that should do it.If not,there is nothing else I can do save install a pump or raise the tower.

The best thing you can do to solve your issues is to purchase a small pump - should be B1500 or less - from a local shop and install in what you have already.

I don't know how many times or people need to tell you that larger or more pipes WILL MAKE NO DIFFERENCE in the pressure. You are wasting your time with that.

Buy a pump.

[chiangrai]

"larger or more pipes WILL MAKE NO DIFFERENCE in the pressure."

If that's the case,a new pipe without the many sharp 90 degree bends that the

present pipe has will be enough of an improvement to give it the small

boost that it needs.

It's a much smaller job than putting in a pump.I will let you know in

a few days if it worked or not.

[canuckamuck]

The tank is only about 20ft above the shower and 30 meters away.

At the moment there is 1 half inch pipe coming out of it,doing the hole house and

the shower has nearly enough power to run the shower.If you hold the shower head at waist height it runs fine,if you hold it above your head the gas cuts out.I'm assuming that this is a safety feature that cuts out when the flow of water is so low that the machine will overheat.

The point is that it only needs a tiny bit more water going through it and I am doing 3 things to improve it.

!-Giving the shower it's own pipe from the tank

2--doubling the size of that pipe.

3--making sure that the new pipe has only one right angled bend in it as the present one has many.

I reckon that should do it.If not,there is nothing else I can do save install a pump or raise the tower.

I would try it your way first, it won't cost much and if it works it works. Otherwise a pump will get you there.