Patio fall from house /drainage

ashe

Hi, looking for some advice please around patio falls. We've had some quotes done for having some patio laid; our existing lawn and patio slopes towards the house slightly. Everything I read about this says it's wrong, but it's already like that and the people we've had quotes off all say it's fine, and they are well regarded local firms. 

The existing patio is only slim and has a few inches of slate between patio and house , but when I dig this out with a trowel it hits concrete after a few inches. We don't have downpipes at all on our gutters at the back of the house, there is one on each side of the house and one on our drive but no gulley to either.

Increasing the size of the patio will then reduce the soil to drain away any rain, and seems like it will then sit against the house?

I'll enclose a few photos of now & what is proposed, sorry for the Picasso as on mobile 😂

Now;two rows of concrete paving slabs behind house and rest is grass

Proposed; pink crosses are gutter down pipes 

How current patio is set up now;

this is with the phone placed flat on patio with camera at the bottom 

This is the layer of slate which runs alongside the whole of the house except where the French doors are 

French doors just have two cut off slab pieces with no slate 

Trying to show the way the lawn slopes towards house 

Side of the house with downpipe visible far right, no gulley to connect to 

Front of house is exact same setup, although there is a gulley in front of garage. 

Not sure what to do for the best as don't want to create (more) sitting water against the house. Is it better if the patio paving was done against the wall at the back of the garden instead of a block in front of the house? But that still doesn't solve the issue of the part that does run along the house. Any advice or guidance would be appreciated!

FreeBear

The slope of the garden looks to be minimal, and certainly nothing that would require major earthworks - My garden also has a similar slope towards the house.. After digging out the base and laying the slabs (sloping away from the house), I ended up with a 100-150mm step up to the "lawn". Forked the soil over and raked it back to give a gentle slope, but then I didn't have a nicely mown lawn to contend with.

ashe

FreeBear said:

The slope of the garden looks to be minimal, and certainly nothing that would require major earthworks - My garden also has a similar slope towards the house.. After digging out the base and laying the slabs (sloping away from the house), I ended up with a 100-150mm step up to the "lawn". Forked the soil over and raked it back to give a gentle slope, but then I didn't have a nicely mown lawn to contend with.

Thanks, I probably wouldn't mind that ad could do some kind of gravel border I guess to hide some of the slope. So is sloping towards the house a monumental bad idea? 

FreeBear

Not a monumentally bad idea if suitable drainage is put in place - i.e. A linear (ACO type) drain is fitted between the house & patio. But this means digging a big hole for a soakaway plus the underground pipework. If you are on a free draining soil, the soakaway need not be particularly big, but a different ball game if you are on clay.

There will be additional costs involved, such as extra labour, SUDS crates, drainage channels, pipes, and more soil to cart away.

ashe

FreeBear said:

Not a monumentally bad idea if suitable drainage is put in place - i.e. A linear (ACO type) drain is fitted between the house & patio. But this means digging a big hole for a soakaway plus the underground pipework. If you are on a free draining soil, the soakaway need not be particularly big, but a different ball game if you are on clay.

There will be additional costs involved, such as extra labour, SUDS crates, drainage channels, pipes, and more soil to cart away.

Thanks. I guess that is my issue, that there is no drainage there now and no plan for it so seems like I need to have a chat. 

stuart45

I wouldn't personally want a patio to fall back into the house walls without any drainage. Even with cavity walls you don't want excess moisture in the cavity. In winter the freeze/thaw on the bricks means there is more chance of spalling.

Silvertabby

Our original small patio was like yours - just a couple of rows of slabs, and a slightly sloping ( towards the house) lawn.

When we had our proper patio installed, the chappie said that we needed to change the 'fall' away from the house, or we'd have trouble.  This he did, plus he installed a drainage channel where the new patio met the new little sandstone step up to the lawn.  

14 years on all is still good.  Incidentally, the chap who gave us a cheaper quote said that it was fine for the new patio to drain towards the house.....