Waste Pipe FAQs

Unless you’re a plumber by profession, the likelihood is that you’re not going to know much about the ins and outs of plumbing and waste pipes. Thankfully, here at BC Profiles, we don’t expect you to! 

Not only do each and every one of our products include descriptions and specifications, but we’ve also compiled an easy-to-follow list of waste pipe FAQs to make sure that you’re fully in the know about any concerns or queries you may have. 

What is the difference between soil pipes and waste pipes? 

Both types of pipe carry waste away from your home to a sewerage system, however, there is a key difference between the two. Soil pipes carry away soiled water from your home’s toilet, urinal or bidet, while waste pipes remove water from the bath, sink, shower and washing machine. 

Can a waste pipe go through a joist? 

Running waste pipes through joists should be avoided where possible, as any drilling of joists (also known as notching joists) may weaken them and compromise the structural integrity. When you do need to notch a joist, you should use the following rules: 

1. Only insert a notch into the top edge of the joist.
2. The notch should be no more than 0.125 times deeper than the depth of the joist itself. 
3. Notches must be no closer than 0.07 the span of the joist to the structure supporting them.
4. To avoid the areas of maximum force and bending in the joist, the notches should be no further away than ¼ of the full span of the joist. 

Can a waste pipe be moved? 

Waste pipes can be moved, however, the process can prove to be a costly one. Rerouting a waste line is problematic as the line is bound to the vertical sewer pipe that connects your home’s waste pipes to the horizontal sewer line. Moving a waste pipe can mean a lot of excavation and digging a new trench to connect to the sewer’s mainline. 

Can you put a waste pipe in concrete?

Waste pipes can be placed in concrete, however, this is obviously a very permanent fixture, so make sure that you measure and measure again before pouring any concrete. The pipe should be positioned while you are working on the foundations, it will eventually come up through the concrete to wherever your toilet is positioned, running below the floor and out to connect with the sewage system.

What temperature can a waste pipe take? 

The working temperature for waste pipes should be limited to 70-75℃ for continuous flow and a maximum of 95-100℃  for higher temperatures, higher temperatures should be cycled intermittently and restricted to two minutes. 

Can you bend a waste pipe?

Should your waste pipe not bend at the correct angle for your system, you can heat the plastic and create the bend manually. This can be achieved by using a stove, boiling a pot of water and dipping the point of the pipe until it softens enough to bend. You can also use a heat gun, though one with a variable setting is recommended so as not to scorch the pipe. 

How do I seal a waste pipe? 

If a waste pipe is leaking, avoid using any sealant. Instead, you should invest in a new pan connector to address the problem. 

What size waste pipe for a sink?

A 32mm waste pipe is recommended for a hand basin, while you’ll need a 40mm waste pipe for a larger sink.

What size waste pipe for a shower? 

A 40mm waste pipe is recommended, however, if you own a large-sized showerhead or power shower, you should use a 50mm waste pipe to cope with the higher flow rate.

What size waste pipe for a bath?

A 40mm waste pipe is recommended for use with a bath. 

What size waste pipe for toilet? 

The standard size for a toilet waste pipe is 100mm in diameter. 

What size waste pipe for a dishwasher or washing machine? 

Your dishwasher or washing machine will require a 40mm waste pipe. 

For more how to’s and information, head on over to the BC Profiles help and advice page, or follow us over on Facebook, Instagram and Twitter.