Fitting Pipes into a Stud Wall

If you are planning to construct a stud wall to create a bathroom or kitchen, it is very possible that you might need to fit supply or drainage pipes behind the plasterboard. As long as you take time to plan where the pipework needs to go, and you are careful when cutting into the studs or noggins, this should not cause too many problems. Here are some simple rules to follow when fitting supply and drainage pipes into a stud partition wall.

Height of the Pipework

Installing pipework behind plasterboard takes a bit of thought. At some point in the future you, or future occupants of your house, might want to drill into the wall to hang shelves or other fixtures. Bear this in mind when position pipes and make sure any horizontal pipework stays lower than about 300 mm from the floor level. This will drastically reduce the chance of hitting the pipe when drilling at a later date.

Planning and Marking the Pipe Run

Plan out carefully where the pipework will need to run and mark the front of the studs or noggins where it passes them.  Transfer the marks around to the side of the studs or noggins so that you can see where you need to drill and cut your notches. Keep in mind when marking the pipe locations that waste pipes need a slight fall along their horizontal length. If you fail to do this, you could have problems with blockages, smells and other problems at a later date.

Cutting Notches for Copper Pipe

To create a notch for a standard copper water pipe, take a drill bit slightly larger than the pipe and drill through the studs and noggins, close to the front face. If possible, feed the copper pipe through the hole before it is all connected up. This helps the stud to retain its strength. If you can’t do this, cut into the stud or noggin from the front to create a u-shaped notch that the pipe can sit in. As long as you don’t cut too far into the face of the stud, this shouldn’t weaken it drastically.

Cutting Notches for Waste Pipe

For waste pipes, which obviously require a larger notch, again take a drill bit slightly larger than the pipe and drill through the middle of the stud or noggin. If you can’t find a drill big enough to do this, hold an offcut of waste pipe against the side of the stud and mark around it. You can then use a smaller drill bit to drill multiple holes inside the circle. The remainder of the waste wood can be remove with a coarse file or a chisel. If possible, feed the waste pipe through the hole before connecting it up. If you can’t do this, you will need to cut into the front face of the stud to create a u-shaped notch.

Before cutting into the hole from the front of the timber to create the notch, cut a 300 mm long by 25 mm deep section out of the front of the stud. Once the waste pipe is in place, you can screw or nail a 300 mm strip of 25 x 50 mm timber into the notch to strengthen the stud.

Insulating Pipework

Insulating pipes which carry hot water helps to keep the water hotter, allowing you to run your water heater at a lower temperature, whilst lagging cold water pipes helps to prevent the pipes freezing and possibly bursting in cold weather. If you are insulating hot water pipe runs, consider if the heat they radiate is contributing to the warmth of the rooms through which they pass. Lagging for cold water pipes is most important in unheated areas of the home such as attics or garages, where they are more likely to freeze. If you are working on a tight budget, concentrate on these areas first. Read our guide on Lagging Pipes and Water Tanks for more useful advice.