NHL Render Below DPC?

[oursurveysaid]

Hi. I've been combatting damp problems in my victorian end-of-terrace (built 1880). I got rid of the concrete slab in front of my front wall, and dug down to the stepped foundation, and hacked off all the cement render that was between the pebbledash and about halfway down the exposed bricks you see in the pics.

The mortar in this wall looks like earth. When I initially took the mortar off, it was like soggy mud, which then dried out. Over the winter it did start to get muddy again though, which surprised me as it's so exposed now. There was some algae on it too, which I've removed.

Anyway, I'm going to slope the ground slightly away from the house at the bottom of the trench, line it with a non-woven membrane, and fill it with 20mm pea gravel which I'll rinse first. I'm hoping this will keep the damp soil away from the house and let the moisture evaporate naturally from the foundations.

I'm unclear about what to do with the wall base though. If I leave it exposed, will it get damp and grow algae, attracting yet more moisture? Should I render it with NHL? I know I shouldn't seal it, but would NHL improve matters?

All thoughts welcome!
TIA

 

[bobasd]

Where's the DPC in your wall? It should be just under the air bricks?
Snap a chalk line across to straighten up the render - cut the line with an angle grinder.
Clean off or replace the badly cement mortar smudged bricks.
Hack out the soggy pointing to 30mm to 40mm depth with an angle grinder.
Re-point in a say 3: sharp sand and lime mortar.

You have a solid wall so damp is presumably present inside the wall?
Any joist tails in the wall might be rotting - although if the hall flooring is new then maybe previous floor repairs have taken place?
You need another air brick - on the left.

You have a yellow gas pipe, and a water or elec on the left?

fwiw: cut back the foliage.

 

[dontbelieveawordofit]

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[dontbelieveawordofit]

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[stuart45]

Looks like it's on top of the air bricks, but could be my eyesight.

 

[oursurveysaid]

Where's the DPC in your wall? It should be just under the air bricks?
Snap a chalk line across to straighten up the render - cut the line with an angle grinder.
Clean off or replace the badly cement mortar smudged bricks.
Hack out the soggy pointing to 30mm to 40mm depth with an angle grinder.
Re-point in a say 3: sharp sand and lime mortar.

You have a solid wall so damp is presumably present inside the wall?
Any joist tails in the wall might be rotting - although if the hall flooring is new then maybe previous floor repairs have taken place?
You need another air brick - on the left.

You have a yellow gas pipe, and a water or elec on the left?

fwiw: cut back the foliage.

Thanks, bobasd.

The DPC is just above the airbricks, which is far too high really. Airbricks are actually above the joists, but I’ve created ducts in the brickwork so the internal holes are below. I’ve had all the joists downstairs replaced with pressure-treated timber and all the timber is separated from the masonry by a plastic DPC now. Walls are internally being finished with Limelite and a breathable paint. The walls used to be damp but they’ve been exposed for a couple of years now and are dry internally.

Yellow gas pipe, then elec, and an old disused lead water pipe (which isn’t leaking). New water main was moled further underground.

Thanks for the advice on the pointing and render. The smudging you can see around the pipes and airbricks is NHL, where I was filling some big gaps. When you say lime, are you talking about NHL 3.5? I dont really want to leave the base of the wall exposed, so would NHL render be ok?