Drainage advice for Sleeper Bed and Patio Floor-based Small Garden

manmediaGQuUkg3r

Hello,

We have a really small "Sort of" garden which we are planning to convert to patio and keep a small sleeper bed area for panting a few small plants. You can get an idea of our new plan on the image (more/less). 

The challenge we are having is to maintain the drainage for our garden. We believe it's better to do Soakway drainage (since we don't have manhole inside the garden) as it would be economic. But TBH, we have no idea whether to excavate and make drains going outside to manhole, or use Soakway. We also don't know whether we can drain the water towards sleeper bed since it might just kill the plants when it's heavy rain or flooding. 

It'd be appreciated if someone can advise something based on their experience

Thanks, 

Lizzie27

@manmediaGQuUkg3r , It would be better just to have a flower bed at ground level with the patio slabs very slightly on a fall towards to it so any surplus water just drains into the ground of the flower bed if that makes sense.
You will need to ensure that the patio also slopes away from the house. The landscapers should be able to advise or if you are doing it yourselves, have a look on Youtube.

Loxley

A soakaway will only work if the soil drains well, so check this. (How long does a hole dug in the ground take to drain after filling with water). Agree with Lizzie re the planting bed, make the paving slope towards it - unless the soil is poorly drained. Reducing the number of slabs by increasing planting or gravel areas will reduce the amount of water run-off and make use of natural drainage.

manmediaGQuUkg3r

Thank you both. would a gravel-filled area be better than patio paving? I also trying to make sure that the drainage doesn't cost me a fortune. So far, it seems the more cutting and adjustment I have to make with Patio tiles and accommodate this drainage, the more expensive it is. Any thoughts? (Sorry, very new to this world  )

Loxley

First off how free draining is the site?

I wouldn't replace all the patio paving with gravel, but just include some gravel areas. For instance pave in front of your doors, where your table and chairs are going with tiles, but infill around them with gravel areas. This should actually reduce cutting, as gravel can fit into awkward shapes and sizes easily. 

Loxley

See below, how whole slabs have been used with gravel. No need for extra cutting. You don't have to have the planting if you don't want.

StephenSouthwest

Gardens don't usually need drainage as such, unless there are particular reasons why drainage is a problem, so you might be worrying unnecessarily.

It's important not to bridge the dpc on house walls, so do be aware of that if you're raising the ground height next to a house. As mentioned above - have a very slight slope away from the house.

Generally (as mentioned above) there's no need to install drainage, unless there's some particular and peculiar reason to need to, water will simply soak into the ground.

raisingirl

It is probably not allowed to connect a drain from your garden into a manhole nearby. So if you have a particular problem with flooding for some reason, a soakaway may be your only option. But as others have said, it would be better if you could just let the whole are naturally drain away across the whole plot - much cheaper 

Nollie

That’s a very smart solution you illustrate @Loxley.

I would also reconsider the porcelain tiles, especially if glazed, as they are impermeable to water, which will then run right off. A natural stone with a riven or textured surface will hold more water and disperse it more slowly. Paving bedded on hardcore levelled with sand, rather than a solid base, will also help drainage.

manmediaGQuUkg3r

This is probably the closes representation (as I cannot seem to upload iPhone pictures to this website due to HEIC format issues). The green patch is where I have regular soil right now. And the sheds are marked in Red. I suppose I save a bit of cost by gravelling it.