Laying a patio - Advice needed!

powerful_Rogue

Hi everyone and thanks in advance!

This is what the area outside my backdoor looks like:


About 5 years ago I bought some weed stopping netting, covered it in sand and then laid some paving slabs on top and cemented them in the middle.



At the time I didn't take into account drainage etc, so think this may have resulted in having to put moisture absorbers into the cupboards that back onto this wall.

Today I have taken up all the slabs and removed all the sand so its back to how it was originally.

I'm planning to put a gully along the bottom of the wall which will then lead down into the garden to drain of the excess water.

My main question is regarding damp proof course look like? The house is 1904 - Is the black at the bottom of the wall the DPC?

VfM4meplse

It looks to me like a DPC (I'm no expert) but I would also get a damp specialist out to see whether it's still working and the extent of damage - if any - to the wall, before doing anything with your patio.

I am reliably informed that damp finds its own level, 1-1.5m up a wall.

powerful_Rogue

VfM4meplse wrote: »

It looks to me like a DPC (I'm no expert) but I would also get a damp specialist out to see whether it's still working and the extent of damage - if any - to the wall, before doing anything with your patio.

I am reliably informed that damp finds its own level, 1-1.5m up a wall.

Thanks for the reply. I had an inkling that might be the DPC.

Good idea to get it checked out before starting any work - It does have a few cracks etc (as you can see from the pics!)

Does anyone know roughly how much DPC costs to be checked?

molerat

I can see drill holes so you most likely have an injected DPC that has been overpainted with bituminous paint.

powerful_Rogue

molerat wrote: »

I can see drill holes so you most likely have an injected DPC that has been overpainted with bituminous paint.

Ah ok! I never noticed them until I saw the photo!

Would you say they need checking or are they normally pretty good? Would another coat of bituminious paint over the top do the job?

Debbie_Savard

In a Victorian house, the DPC would often be two layers of slate in mortar.



There appears to be something like this in the last of the OPs pictures just above the concrete patio slab

I'd guess the DPC wasn't fully bridged until the slabs were laid, but splashing from rain onto the concrete would have caused some damp hence the chemical injection.

I'd certainly remove the concrete slab, drop the ground level by 15cm and relay slabs plus a dry channel

powerful_Rogue

Debbie_Savard wrote: »

In a Victorian house, the DPC would often be two layers of slate in mortar.



There appears to be something like this in the last of the OPs pictures just above the concrete patio slab

I'd guess the DPC wasn't fully bridged until the slabs were laid, but splashing from rain onto the concrete would have caused some damp hence the chemical injection.

I'd certainly remove the concrete slab, drop the ground level by 15cm and relay slabs plus a dry channel

Thanks for that.

I wasn't looking at getting rid of all the concrete, however maybe digging down around the house and adding in a gully. Was hoping that might do the job.