FAO any builders/surveyors or someone who might know

[starting_11]

There seems to be some sort of sinking going on down the side of the grass at the side of my house.

You can see the line running down the side of the bricks and there is a funny hole which is always wet you can see below the black pipe (that side of the house is in permanent shade).

There is a pipe (white one) running out down there from the upstairs bog I think.

Does anyone know what is causing this and if it's a problem. If so, who should I speak to? (House is about 4 years old and still covered by NHBC).

Thanks

[Sausage]

I think you've answered your own question. Ultimately you could try invoke your NHBC guarantee but it might fall outside of the 2 year defect period.

The white pipe looks to be too small for a toilet outlet. More likely to be from a basin. Does the ground smell of sewage?

Personally I'd photograph it (you've done that) and then I'd tentatively dig out around the two pipes to see if there's anything obvious that could be fixed by a local tradesman. This will be quicker by a long distance than trying to get the housebuilder to sort it or seek recourse to the NHBC. It's also more likely to be cheaper and less frustrating.

[starting_11]

The ground doesn't smell of sewage. I've not really poked around too much, I've just noticed it over the last few months coming and going.

Are you thinking there might be a collapsed drain or something below it?

[Sausage]

It's unlikely to be a collapsed drain because you'd have noticed a long time ago. It might be as simple as the fact that you've got a north facing wall and possibly a heavy clay soil. Either way, I'd dig around it so that you don't have to get someone else to do it and pay them for the privilege. I must say I'm surprised that there isn't a gravel trench along the length of the wall. I thought that was pretty standard on new builds these days.

[starting_11]

There's gravel along the flag stones to the other side of the house. I hate that bit of grass there, it serves absolutely no purpose, makes access to the drive harder when a car is parked on it and just gets chewed up by the lawnmower because it's always damp.

I might look at taking it out and slabbing it like the other half of the house.

[ClaretEngineer]

There's gravel along the flag stones to the other side of the house. I hate that bit of grass there, it serves absolutely no purpose, makes access to the drive harder when a car is parked on it and just gets chewed up by the lawnmower because it's always damp.

I might look at taking it out and slabbing it like the other half of the house.

I see you have some of that lovely grass similar to what I have. Is the site a former field?

[starting_11]

Nah there were buildings here before.

I take pride in my lawns but it just never gets any sun on it. It's just a wasted piece of grass!