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How To Fix A Leaking Plastic Water Pipe Joint

Upon discovering a leaking pipe the common instinct is to panic and call a plumber to fix the problem as soon as possible, without a thought to the price or if you could infix the pipe joint for yourself. The actual task of fixing the plastic piping can be an easy one with minimal skill needed to replace or restore the piping and its joint and stop any future leaks. If you’re wondering indeed how to fix a leaking plastic water pipe joint, follow my guide and get the clear idea to fix that.

The first step whenever a leak is discovered is to find its source. This is not always as easy as it seems, as the plastic piping goes as far as the houses foundations in some cases it may be a harder task than initially thought. However, the first step is to mop down the surface, wiping up any excess water to ensure that this is not mistaken for where the leak in the pipe actually is. Then with a torch survey the area and locate the actual crack or opening in the piping joint that is causing the leak. Then to help remember where the crack in the joint it, mark the source for reference whilst deciding how to solve the issue.

How To Fix The Leak?

Once the source of the leak has been clearly highlighted the water should be turned off at the mains to avoid any more water damage. If you can locate the specific water valve, or the area of which you are working in, as opposed to turning the water off at the mains then please do so. This is stop disruption for the rest of the household and their access to clean running water.

As there are many ways to fix a leak in plastic piping joint, it really depends on the severity of the leak and the likelihood of it becoming a problem area if the pipe isn’t completely refitted as opposed to fixed. If the leak is coming from joint usually it is believed that the whole fitting will need to be replaced, as swapping and changing individual pieces of piping are not favourable as they are not interchangeable, they are sold as a unit and work as a unit in almost all cases. This is in fact a worst-case scenario, and fixing the plastic pipe joint yourself is an option, if these next steps are followed correctly.

Removing the Damaged Plastic Piping Joint

If the leak does require removing the piping joint then it is important to remove a larger amount of piping than is visibly ruined or leaking. This is to ensure all of the damaged area is removed and the job that you are undertaking is meaningful and not a regular occurrence.

Cutters are needed to remove the damaged piping joint, they should be placed at a 90-degree angle and make a straight cut through the piping at either end of the piping joint. After this there may be a build up of water that will need to be drained, allow for both sides of the piping to drain through, then clean up the surrounding area of debris and water.

Fitting a New Piece of Plastic Piping

After purchasing a replacement plastic piping joint and piping it might be beneficial to assemble this into position whilst it is still dry.

Dry fitting means to fit without using any special bonding agents, glue and priming that will be needed to ensure the pipe is held in securely. 

Fitting New Piece of Plastic Piping

Dry fitting allows for adjustments and tests to be made to ensure that the pipe is in the correct position and is the correct length. This is an important step if you are undertaking this task on your own, without this planning period the likelihood of the piping being fixed incorrectly is higher.

Applying a Plastic Piping Primer and Cement

This step requires the purchase of primer and cement for PVC and plastic piping, these can be found in many hardware or handyman stores, in the plumbing section.

Prime the piping to start by using an application brush, coat the outside of the replacement pipe joint and the inside of the fitting already in use. The primer removes the shiny surface on the plastic piping, getting it ready to apply the cement so it will bond correctly. This can take up to fifteen minutes to dry off, so let it get to work for a while before moving onto the next step.

Applying the cement is practically the same actions as applying the primer; repeat this process using a generous amount of cement on the outside of the replacement pipe joint and the previously used fitting.

Insert one end of the pipe joint into the previously used pipe, this is done with most ease by twisting the piping as it is pushed into place. By doing this it ensures that the piping is in the correct spot and that the cement has spread over more of the old piping to increase the chances of bonding.

If you are attempting to fix this on a plastic joint then this step will need to be repeated on the other side of said joint to ensure that the new pipes are bonded to the best of your ability. The glue should be able to cure for at least 15 minutes, but that is further specified dependant on the product that has been purchased.

Alternative Methods

If it is believed that the leak is not as damaging as initially thought and does not need to be treated by removing the whole plastic pipe joint, then there are alternative methods which can be adopted to stop the leaking joint.

Repair Tape

Using a rubber or silicone repair tape will help plug up the leaking plastic point with ease. The thick, heavy-duty tape sticks to itself as opposed to the piping that you are fixing. If the tape is wrapped tightly around the leaky joint, using it well above and below the damaged area it can stick to itself and increase its compression on the affected area. It is beneficial to use as it can travel easily up a damaged pipe, but can be hard to apply in tight spaces much like where plastic piping is located.

Fiberglass Wrap

The fiberglass wrap is in essence a fiberglass cloth; this has to be coated with water to activate the resin, which makes it easily to mould and dry hard and durable. The cloth is applied around the leaky pipe joint by hand and within twenty minutes the wrap hardens and the leaky plastic water pipe joint is fixed.

Rubber and Hose Clamps

This is usually a temporary response to a leaky pipe, by using a thick piece of rubber and a few hose clamps to quickly repair the issue. If the leak is in one singular area of the pipe and not over a joint or a whole length of pipe rubber can usually be stretched around it. Then the hose clamps need to be opened all the way, this makes them easier to stretch around and down the pipe and into the correct position. The hose clamps then need to be tightened around each end of the rubber; this compresses the rubber piece over the leak and stops the leak to give some time until permanent repair is needed.

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