How many bricks below DPC can be exposed?

[berty3000]

Parts of my house have 3 bricks below dpc exposed above external ground level. House is a detached 1960s bungalow on relatively flat ground.

What I would like to know is - is this ok and what are the limits? I know that there are supposed to be at least two bricks courses between an outside surface and the dpc, but how much is too much? How about 4 or 5 courses? Another way of asking might be, what is the minimum amount of earth or other material that has to sit above the foundations alongside a house up against the exterior wall that rises from the footings?

Thanks

 

[noseall]

Parts of my house have 3 bricks below dpc exposed above external ground level. House is a detached 1960s bungalow on relatively flat ground.

What I would like to know is - is this ok and what are the limits? I know that there are supposed to be at least two bricks courses between an outside surface and the dpc, but how much is too much? How about 4 or 5 courses? Another way of asking might be, what is the minimum amount of earth or other material that has to sit above the foundations alongside a house up against the exterior wall that rises from the footings?

Thanks

You could dig down to the top of the concrete if you wish.

 

[^woody^]

You could dig down to the top of the concrete if you wish.

Not always.

Often, the foundation bricks are not frost rated and are any old crap, and may change to engineers or facings from 9" below ground level upwards.

Plus, the foundation walls are not face work - although admittedly, there's little often difference nowadays.

 

[berty3000]

Any thoughts about by questions, taking an average case? As mentioned, site is relatively flat, soil is somewhat heavy northwest type.

Would 800mm below surface to bottom of footings seem typical... or 1m below dpc? House was built in 1961. The bricks I can see below doc are the same as the ones above it, including 5 or so below dpc.

And in terms of basic principles, how much soil needs to be above the footings against the sides of the house and why?

 

[noseall]

Not always.

I was answering in terms of structural integrity rather than aesthetics.

 

[^woody^]

 

[^woody^]

And in terms of basic principles, how much soil needs to be above the footings against the sides of the house and why?

None.

The other questions were answered.

 

[oldbutnotdead]

Older houses with shallow or no foundations you need to be a bit wary of surface water washing out exposed soil.
If you have good deep founds then no real issues having those lower courses exposed

 

[berty3000]

None.

The other questions were answered.

I've been told by a builder that they always aim for a 45 degree line from the base of footings to any trench, such as for drainage. Why is this necessary when it doesn't matter how much soil or other material is up against the side of the foundations?

 

[berty3000]

I've had this drainage pipe installed down the side of my house to remove excess surface water from front garden to rear garden area where it drains much better. The pipe has some perforations in the top half to also collect water from down the side which would get some pooling in rainy conditions. The bottom of the trench is probably 6 bricks below dpc at the point nearest on the photo, going up to about 4 bricks below further away. The trench was filled with pea gravel, membrane over the top, and finished in a few inches of gravel, the top of which finishes 2-3 bricks below dpc from one end to the other. The trench will get water in it when it rains although the pipe will carry some of that away if it fills up...

is any of this likely to be a problem for the house, foundations etc?

 

[stuart45]

The weight of the building is transferred to the ground from the base of the foundation at an angle of roughly 45 degrees, known as the angle of repose.

 

[berty3000]

The weight of the building is transferred to the ground from the base of the foundation at an angle of roughly 45 degrees, known as the angle of repose.

Thanks Stuart, that's interesting. I'd misunderstood what he meant then I think. So is the angle taken like in this image, so that you don't want a trench in the shaded area? Presumably becomes of less significance after a certain distance.

 

[stuart45]

That looks about right.