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Blocked Drain - Can I Cut Plastic Membrane Covering Man Hole?

Postby b0ssd0g » Mon Mar 09, 2015 2:09 am


After some advice if possible? Sorry for any bad terminology! :)

The kitchen waste pipe has been overflowing on to the patio for a week or so, so today I found time to try and clear the blockage.

I found a lot of solid fat deposits in the external drain trap and cleared it all out by removing the internal sleeve and it all looked good but unfortunately the water was still not running away.

On to the 1st small manhole which is in place because the drain bends 90 degrees and heads off down the side of the house - I removed the cover and found masses of fat had solidified in the exposed channels. Again I removed all this and reached up the pipes in both directions as far I could but the pipes were still blocked.

Clearly I need to get some drain rods to clear the pipes properly. I'm happy about doing this but I have one question which is the reason for this post.

The next manhole (which is larger) is further down the side of the house and is the point where the toilet waste pipe enters the system. The toilets are not overflowing and appear to be flushing away normally so I'm assuming the system is ok from here. I lifted this manhole cover and found a plastic sheet/membrane was in place completely covering the hole and preventing any further access. My concern is that if I push the rods down the pipe from the 1st small manhole, I'm just going to shove everything further down the system - it obviously all needs to be properly removed and disposed of.

So I imagine this plastic sheet is in place to control any odours but may simply have been left there by the builders to stop any soil falling into the cavity? But in order to clear the pipes properly, and avoid potentially blocking the toilet outlets, I'm going to have to cut through it. Is it ok to cut this plastic sheet and should I repair it after the work is done?

Thanks for reading.
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Simply Build It

Postby thedoctor » Mon Mar 09, 2015 11:32 am

From what you have said the plastic membrane is stopping access to a manhole. The other name for a manhole is an access chamber so please do cut away and allow access. I suspect that the membrane was placed as you say to prevent soil being kicked into the manhole when work was being done but it should most definately not be there now.
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Postby b0ssd0g » Mon Mar 09, 2015 2:32 pm

Thanks for your advice - much appreciated.
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