New build. Drain issue.

Hi there, It sounds like you definitely have a blockage, if it’s a new build there should be an access panel on the soil stack and failing that there should be a manhole cover in the garden this would be my first point of call for an inspection, Don’t let the builder/plumber fobb you off they should be inspecting the drains without seeing the problem first hand as it’s only going to get worse, if they refuse I’d go to the federation of master builders who will be more than happy to assist, Hope this helps 👍

Hi, This is very likely due to an incorrect fall on the horizontal part of the soil pipe. Please let me explain... The soil pipe is the pipe that exits the rear of the toilet pan. The soil pipe will then go through the wall and out of sight, and in most cases soon after will join with the soil stack. The soil stack is the vertical part of the soil pipe which stands upright and travels to the ground, and then underground into the drain. When you have an en suite, the horizontal part of the soil pipe will need to travel further to reach the vertical soil stack. This is because it will use the same vertical soil stack as the main bathroom in the property. Therefore this horizontal part of the soil pipe should have a continuous gradual fall away so that the solids (poop) and toilet paper slide along the pipe with the water when the toilet is flushed. If the gradient of the fall is too steep then the water will rush past the solids leaving the solids laying in the pipe. However, If the pipe doesn’t enough fall then you will have the same problem, solids sitting in the pipe. If this happens the solids build up over a short period of time to a point that it delays the flushed water from running away. This shows in the way of the water rising in the toilet bowl. The solution is to check the fall on the horizontal part of the pipework. This can be determined by a knowledgeable plumber looking at the installation of the soil pipe to check all has been installed correctly. The fall or drop should be anything between 1/40 (1cm drop for every 40cm across) and 1/110 (1cm drop for ever 110cm across). This will get your poop slipping through the soil pipe and not getting stuck half way down! I hope this helps 👍

partial blockage in soil system.