Is this subsidence? Photos included. Please help

[BloodyStupidHouse]

I live in an extended 3 bed end terrace. 8 years ago I had my kitchen extended and it was a big job.

All signed off and no issues at all until about a month or so ago, maybe a little longer.

I noticed cracks inside above the door. Looking outside, there are 'stair stepping' cracks in the pointing, again above the door.

My worktop has dropped at one end. My door appears to have dropped - it won't shut properly

There is also what appears to be a distinct dip in my lawn - directly outside the extension on the corner.

My neighbour has some very tall trees in his garden right next to mine. They're well over house height and about 17 feet to the side of the extension. These weren't deemed an issue when the build went ahead

My buildings insurance company said it isn't subsidence and they've got no suggestions for me. They are basing this on a telephone call where they asked me 3 questions

I have had the original builder back out. He is puzzled and doesn't know what it could be - there have been no issues until the past few months

Any suggestions for me please? Do I need a chartered surveyor? Is this really not an insurance issue?

@Campervangirl thanks!

Check if the door has the correct lintel … ours didn’t and that crack on the outside is exactly what ours looked like.

The fact you've got salt efflorescence on the lower courses of bricks would indicate moisture is bridging the damp proof course. Earth shouldn't abut brickwork and the bris is are porous and will absorb moisture

Trees being chopped down can lead to problems. Think it's called heave? Changes water level in soil

These are the trees in relation to my house - prior to then being cut a few weeks ago

@hedgehogger1 they were only lopped at the top a few weeks ago

Thanks @Namechangehereandnow

A dip in the ground at one point is most likely (quite a bad) leak.

Get your spade out and stop worrying about the trees.

I would have thought the effloresence would be below the DPC, unless the leak is into the floor slab. Take some closeups please.

There is a lot of it, seemingly just along the one wall, close to the probable leak.

It has been an extremely dry summer and that means especially on clay there has been more movement than usual so minor cracks have appeared in a lot more properties than usual. Minor movement cracks are not an issue and can be remedied with decoration and repair however agree with PJ that the dip in the lawn sounds like a leak and that's more of a concern that you need to investigate asap. The trees wouldn't concern me.

Where is your washing machine?

Thanks a lot @PigletJohn

What shall I take close ups of please? Which photos? This is all Greek to me, all the terms although I'm certainly learning

Trees can cause soil to shrink or heave in time, or if conditions change. Clay soil is the most shrinkable. There's NHBC guidelines for foundation design about it. I used to do this for my job.

However, apple and cherry are not particularly high water demand species, so I wouldn't worry about it.

I agree that the dip in the lawn suggests a broken drain/pipe, which could be leading to further problems.

You'd know if your soul is clayey is you dig it. Does it have a consistency like plasticine? Could you roll it into sausages without them falling apart? Anyway.... I think it's most likely to be a broken pipe/drain. Grass on clay gleans can survive a hot summer - mine has anyway - because when it's rained, it's really rained!

@PigletJohn good question. The washing machine is under the first window - I've squared it. The round circle is my tumble dryer vent

@PigletJohn the dip is subtle but I can feel it underfoot. It was flat and now it's not. The dip comes to the right of the down pipe

Washing machine was broken with a different issue. In the last few months I've pulled it out completely to replace the carbon brushes and didn't spot anything amiss

How long since you noticed cracking? Subsidence tends to happen over a period of time which is why insurers use "tell tales" to monitor. Removing trees can cause more problems than it solves, especially if they are not the cause.

Were all building regs followed with modern foundation depths etc? Some settlement is normal but again tends to appear over a period of time.

What does the downpipe drain into? A drain connected to the sewers or a soakaway?

@C8H10N4O2 noticed the cracking in past couple of months or so

Trees weren't removed - and only lopped off as a separate issue as they put my garden in total shadow bar a sliver at the end!

@Surtsey now that I don't know! Wouldn't like to guess. I shall try and find out

They haven't been chopped down though, just cut back. I don't think that would have a significant impact on the soil

Are the cracks in an extension

Removing existing trees causes the ground to heave, not subsidence.

get a ruler and mark the distance across the crack - say a 6 inch line and you’ll know if it gets worse

@Synny yep. All the issues are centred around the extension which was done 8 years ago

The main house is absolutely fine. It's just this kitchen extension. And no issues until a couple of months ago when I noticed cracks, dip in the garden, the extension door not closing properly and my counter top dipping