Porch Floor

[Night Owl]

Hello everyone,

 

First post here but have been reading the forum for some time.

 

I am currently renovating our 1950/60s dormer bungalow.  Trying to sort out some damp issues at the moment in a front (west facing) bedroom.  Initially I found that the floor is solid concrete with a bitumin coating under a wooden parquet floor.  I found that when the property was plastered they plastered down below floor level therefore water was being sucked up through the plaster. 

So, where is the water coming from?  I reckon it is coming from outside under a porch extension that was added circa 1980.  I get a lot of standing water on the driveway and also there is a rain water drain adjacent which probably goes to a soakaway somewhere.

 

 

         

 

The ground level is very high, you can see the slate DPC barely 1 brick above.  Solid concrete with a tarmac covering over a large area.  I don't have the funds to reduce the ground level.  The porch is much the same with the floor level below DPC!  Yesterday I dug an exploritory hole in the porch floor adjacent to the dwonpipe.

 

  

 

As you can see, the wall below the DPC was very wet.

 

 

 

The floor is solid concrete ontop of balast down to about 220mm.  There is no damp proof membrane and no foundation for the porch low brick wall.  I shall be doing some more investigation to find out where the water is coming from, however the question I have is how to best relay the floor.  In particular, I want to get the damp proof membrane right.  I would like to raise the porch floor level a little but will hit problems around the front door as it is virtually at ground level with not much room above to play with.

 

Any advice appreciated.

 

P.S I can't afford to knock porch down and start again which would be the 'money no object' solution!

P.P.S Apologies about picture sizing, not very good with IT!!

 

 

 

 

 

 

 

Edited December 14, 2023 by Night Owl
Amend pictures

[Conor]

Fit a threshold / Aco channel drain all along the porch and affected areas. Make sure it has somewhere to drain to that's effective. 

[Night Owl]

Thanks, will take a look at that.

 

Stuck the hosepipe on the rainwater pipe this afternoon, however no water was noted in the hole I dug.  Its possible that the water could be entering on the porch front wall and tracking back to the house wall.

 

 

For this age of property, how close to the wall is the rainwater soakaway likely to be?

[Marvin]

Officially a minimum of 3 meters. I use drain roads, cable access rods or a hose pipe to measure the length of the pipe underground. Which ever will go down the pipe depending upon the access angle /size.

[Night Owl]

Looks like the porch is on a bit of a slope.  Dug out another hole today at the front of the porch, however it seems to be only half the depth of the one next to house outside wall.  I need to look deeper into damp proof membrane and external drainage.