Rear Garden Level?

[stephenevans]

My garden and patio are level with the door threshold and DPC.

My understanding is that the ground level needs to be 150mm below DPC or at a minimum 75mm below with a 200mm+ gap filled with gravel that can drain. I understand that having level access is good, but this should surely slope away or be a step (like our front door).

I want to patio at the rear side up to the house and half way down the garden. But to meet regulations, I believe the patio level will need to drop at least 75mm, if not surely 150mm. This would require the entire garden to drop, or to have a step up to the grass level. This is a lot of work and surely shows the ground level is too high?

I have been struggling to find if this does break any regulations, any help would be appreciated. I can upload more photos if needed.

Thank you, Steve

[stephenevans]

additional photo

[New Home Expert]

It is true that the external wall DPC should be at least 150mm above finished ground level.
The key words are "should be" which is different from "must be"

The reason is this, as rain falls it splashes back off the ground and it is widely believed that this would be less than 150mm meaning the dpc would stop any splashes soaking the bricks above the dpc.  Obviously primary purpose of the dpc is to prevent rising damp, but the 150mm is for splash back reasons.

Unless the wall is getting saturated, neither the NHBC or builder would do anything about it, even though it is not right.
Using a "trench" filled with drainage stones at 150mm below is often used as a cheap solution to the defect but it is not an alternative or approved.

Good news, from your photos, I see one airbrick. These are normally located on the dpc course so you may just have a dpc 150mm above finished ground level.  That said, if the airbrick is for underfloor ventilation there should be more than one!

There are many posts on this forum about ground level dpcs. Quite why the housebuilders can't even get this simple rule right after decades is beyond m.

[stephenevans]

Hi, thank you for your reply.

Yes, the airbrick was located two bricks lower on the DPC, but when I mentioned to the builder about the patio level being so high, they sent someone to move the airbrick up.

If it will only be acted on if the wall was getting saturated (wet?) then I guess I am stuck as the little path of patio they put in will not cause this issue. The issue will come when I install my own patio.

I was wanting the builder to lower the entire garden to where it should be, which then saves me the time and money to fix the issue myself.

But it sounds like that is not something that will be possible from what you have said.