House Purchase - Dodgy Septic Tank

bemak

Hi all. Just looking for a bit of general advice from people who might have experienced something similar. 

After years of searching we've finally gone sale agreed on a house we really like. The house is on the extreme upper end of what we can afford but we're happy to go there for the right house. We had another viewing last night to give the house another good look. When my wifes brother was in the shed he noticed rodding equipment which led to the assumption that there may be issues with the septic tank. 

We were able to lift the manhole of the septic tank and noticed a lot of water in the manhole itself which is a bit odd particularly after a period of fine weather. We also lifted a manhole on the drain to the septic tank and flushed a toilet in the house to see what the flow was like but it was quite poor and there was evidence of 'sediment' in the manhole when we inspected it. I touched base with a colleague in the industry about this and they said that the 'sediment' in the drain could be due to it having insufficient grade to the septic tank. He also mentioned that the excess water found in the septic tank could be caused by a number of factors, including a high water table which could be penetrating the tank. 

We asked the vendor about this and they said that it's been years since the septic tank was emptied which is "probably the problem". My concern now is that, if this is the case there's probably irreversible damage done to the tank/percolation area and that we're probably looking at an expensive fix if we were to process the sale. 

The vendor has agreed to empty the septic tank to aid in diagnosing the problem when we get the surveyor in. I was just wondering, if it turns out that there is a major problem with tank itself do we have much leeway? 

I looked up the planning file (from 1990) and the septic tank and percolation area was conditioned to comply with "SR6/1975". When I looked up this regulation I found this interesting section in it:

CONSTRUCTION OF TREATMENT WORKS

4.2 Drain to Septic Tank
4.2.1 The drain to the septic tank should be at least 100mm in diameter. This drain may be of earthenware, concrete, asbestos cement or uPVC laid at a grade to give self cleansing velocity and jointed to give a watertight drain.

If we find that the grade of the drain is insufficient to give "self cleansing velocity", do we have a valid argument?

Thanks!

Del2005

You have 2 choices. Buy and fix the septic tank or walk away. The vendor isn't going to fix something that they are selling. Depending on the demand in the area you may be able to reduce the cost to purchase, but that's totally up to the vendor.

TomOnBoard

bemak wrote: »

Hi all. Just looking for a bit of general advice from people who might have experienced something similar. 

After years of searching we've finally gone sale agreed on a house we really like. The house is on the extreme upper end of what we can afford but we're happy to go there for the right house. We had another viewing last night to give the house another good look. When my wifes brother was in the shed he noticed rodding equipment which led to the assumption that there may be issues with the septic tank. 

We were able to lift the manhole of the septic tank and noticed a lot of water in the manhole itself which is a bit odd particularly after a period of fine weather. We also lifted a manhole on the drain to the septic tank and flushed a toilet in the house to see what the flow was like but it was quite poor and there was evidence of 'sediment' in the manhole when we inspected it. I touched base with a colleague in the industry about this and they said that the 'sediment' in the drain could be due to it having insufficient grade to the septic tank. He also mentioned that the excess water found in the septic tank could be caused by a number of factors, including a high water table which could be penetrating the tank. 

We asked the vendor about this and they said that it's been years since the septic tank was emptied which is "probably the problem". My concern now is that, if this is the case there's probably irreversible damage done to the tank/percolation area and that we're probably looking at an expensive fix if we were to process the sale. 

The vendor has agreed to empty the septic tank to aid in diagnosing the problem when we get the surveyor in. I was just wondering, if it turns out that there is a major problem with tank itself do we have much leeway? 

I looked up the planning file (from 1990) and the septic tank and percolation area was conditioned to comply with "SR6/1975". When I looked up this regulation I found this interesting section in it:

CONSTRUCTION OF TREATMENT WORKS

4.2 Drain to Septic Tank
4.2.1 The drain to the septic tank should be at least 100mm in diameter. This drain may be of earthenware, concrete, asbestos cement or uPVC laid at a grade to give self cleansing velocity and jointed to give a watertight drain.

If we find that the grade of the drain is insufficient to give "self cleansing velocity", do we have a valid argument?

Thanks!

If the tank hasn't been emptied in ages, the outflow and percolation area may have been blocked up with solids by now. Emptying the tank will give short term relief, but if the piping downstream of the tank is blocked up, the same issue may recur as soon as the tank refills with liquid.

I'd factor in the cost of a percolation area repair and see if vendor will adjust price to reflect that.

bemak

This is what I was thinking too - and if we were to factor in the cost of replacing the percolation area - we'd probably be as well off to replace it all for peace of mind.

Lumen

OK, so from experience and understanding of my own 30 year old tank, passed on from the previous owner...

bemak wrote:

We were able to lift the manhole of the septic tank and noticed a lot of water in the manhole itself which is a bit odd particularly after a period of fine weather..

Why is it odd? Tank is supposed to be full of water. The solids sink, the liquids go out to the percolation area from the top outlet.

bemak wrote: »

there was evidence of 'sediment' in the manhole when we inspected it

There is supposed to be sediment in the tank. When it fills up (every 5 years or so in my case) you get it pumped out. Other than that, it's zero maintenance.

bemak

Lumen wrote:

Why is it odd? Tank is supposed to be full of water. The solids sink, the liquids go out to the percolation area from the top outlet.

There was a big ****€ sitting in the drain essentially. That's not normal, should have been long gone down the line

Lumen

bemak wrote: »

There was a big ****€ sitting in the drain essentially. That's not normal, should have been long gone down the line

Ah right, the drain manhole not the tank manhole.

Still, I don't get the bit about irreversible damage to the percolation area. That comes from solids getting in, which you're suggesting may have happened because there is too much liquid in the tank, but there is supposed to be liquid in the tank, that's how it gets to the outlet.

Even if solids have reached the percolation area (which there seems to be no evidence of in your OP), you can't assume there will be problems.

Last year I left my tank too long before emptying and a load of sediment got into the percolation area. I got it jetted and no problems since.

In short, it seems like you've gone from "turd in the drainpipe" to "rebuild septic system" in one giant, unsubstantiated leap.

bemak

Lumen wrote:

In short, it seems like you've gone from "turd in the drainpipe" to "rebuild septic system" in one giant, unsubstantiated leap.

🙄

bemak

That last post was an emoji. I can say for sure that the drain to the septic tank doesn't have sufficient grade. I've had that confirmed.

TomOnBoard

bemak wrote: »

That last post was an emoji. I can say for sure that the drain to the septic tank doesn't have sufficient grade. I've had that confirmed.

If thats the case, that may be the only problem and the perc area may be fine. Unfortunately, if the flow from the house to the tank is inadequate, it's hard to see how the issue can be resolved without some serious work.

bemak

TomOnBoard wrote: »

If thats the case, that may be the only problem and the perc area may be fine. Unfortunately, if the flow from the house to the tank is inadequate, it's hard to see how the issue can be resolved without some serious work.

Looks that way unfortunately

TomOnBoard

bemak wrote: »

Looks that way unfortunately

If it's factored into the selling price you could consider trying a pumped/maceration solution from a holding tank at or near that manhole, assuming that the fall from the house to that point is ok.

elperello

You say you really like the house.
I wouldn't let this problem put you off.
Try to negotiate a bit off the price.
Ask around locally and there will possibly be a "go to man" for septic tank problems.

bemak

elperello wrote: »

You say you really like the house.
I wouldn't let this problem put you off.
Try to negotiate a bit off the price.
Ask around locally and there will possibly be a "go to man" for septic tank problems.

Hopefully. The EA is currently asking for a professional opinion on that side. I doubt they'll get anyone to sign off on it - who would!

bemak

EA came back to say house was being sold as is. Obviously they couldn't get anyone to contradict what we thought of the septic tank. Unfortunately we've had to pull out as it was just too expensive for us considering everything. Thanks for all your advice on here. Hopefully we have more luck next time

bemak

Just wanted to follow up on this in case it was useful for someone else. 

Was speaking to a septic tank manufacturer and installer. His parents actually lived two doors away from the house we were looking at so he knew the area and ground conditions well. 

He said that given the age of the property, the septic tank would not be compliant by today's standards and would need to be replaced. Interestingly, he said that a bank would not let us draw down the mortgage until the tank was made compliant and that they would typically hold back three times the value of the works until the works had been completed. 

With regards our situation, he said that the area where the property is located not only has very poor drainage but also a high water table. So if we had proceeded with the purchase, we would need to put in a raised bed system which brings it's own issues i.e. takes up space in the garden and may require PP. In all, he estimated that the cost of a job of this nature would be in the region of 10-12k but that it would qualify under the HRI scheme.

TomOnBoard

bemak wrote: »

He said that given the age of the property, the septic tank would not be compliant by today's standards and would need to be replaced. Interestingly, he said that a bank would not let us draw down the mortgage until the tank was made compliant and that they would typically hold back three times the value of the works until the works had been completed. 

It doesn't matter when a tank was installed, if it is working ok. A tank that was installed in 1980 to the standards that prevailed in 1980 is still perfectly OK in 2018, assuming that it is working to the 1980 standard. Otherwise, everyone seeking a mortgage would automatically have to replace any system not conforming to today's standards and that would be ridiculous, UNLESS the system was not working.

In your case, the issue of possible replacement arose only because you established that SOMETHING was amiss, and there was a risk that the whole system or parts of it were FUBAR. If the system was working OK, the question of replacement wouldn't even have arisen.