How much for a damp proof course?

[RelievedItsOver]

Hi all,

I live in the NW in a 1930s semi. I've notice damp at the front of the house where my porch is. It comes up to about a brick or two high in the front porch. It is probably just as bad around the front bay window, although there are no signs of water coming coming through the internal brick.

The pointing in that area is shocking so I will need to redo that when the weather is dry.

I have a damp proof contractor coming to take a look at my property on Saturday. Just wondering if anyone has had theirs done recently and how much it cost? Is it worth calling out an independent surveyor instead?

TIA.

Where is the ground level in relation to the DPC?
1930’s houses have DPC’s that rarely fail.
Is the porch original?
A few pics would help the armchair analysts.

I can try and post some pics tomorrow if it helps? Bit too dark to do it atm. One thing that makes me a bit.... hmmm 🤔 is the fact I have a drain at the front of the house so maybe it's that that's the problem, plus I have leaky gutters. I'm hoping to have the roof repaired for leaks soon and I'll ask the chap to sort the gutters too. The gutters arent old at all, but the guys that did them didnt sort the leak and I dont want to deal with them again.

I cannot see where the original dpc is.

New DPCs aren’t usually the best way forward.
Have you identified the source of the damp? For example I’ve got damp at the base of a couple of walls and it’s because of crap gutters and the water splashing against the bottom of the walls in certain places.

It could be my gutters as they constantly drip in two places (one near the bay window and one near the corner of the porch). I'm now worried about the rainwater drain at the front of my house causing problems. I'm thinking the worst and I dont know which way to turn. Is it worth getting a structural survey as opposed to damp proof contractors?

You need neither. Get the guttering and any down pipes and drains sorted out, and wait for the summer.

When you say a DPC I think you mean silicone injections which are not the same thing

and are rubbish

If you can work out what the building defects are, causing wzter ingress, you can put them right. Injections will not do that.

I recommend that you do not allow anyone who sells silicone injections near your house

I've scouted MN last night about this and saw that injections are no good. I'll see what the guy says in Saturday. He might try and sell me them.

My house is accrington brick at the front - will that have a dpc membrane?

Beautiful bricks, irrelevant to the DPC, though accringtons are practically water proof.
You will have a dpc, 99% sure of it.
If you have a leaking gutter, that drips onto concrete, the drips can bounce so can bridge the dpc. It’s important to have at least 6” between height of ground and dpc.
You say you don’t have damp inside, so no need to panic.

Thanks @C4tastrophe I do have a very wet internal porch wall. It's still a bit dark to photograph and I'm heading to work very soon so may not get chance to take some. I will do so you can see what I mean. Do you think if I sort the gutters it will rectify the fault? Weirdly the wall which is worst damp (internal porch wall), the gutter doesnt drip as much as the more problematic drip.

I really hope roofer chap takes a look next week 🤞🤞

I wish I knew what I was doing

If the damp is on the outside of the porch and the gutters are crap then it could be causing the damp. It’s splashing quite high up the wall
I will take a photo of my damp tomorrow in the light. I have just ordered new guttering to solve my damp issue.

I'll post a pic when I get decent daylight. Might be the weekend now. The internal brick in the porch (so through two layers of brick) is wet to the touch.

The bay window dampness doesnt appear to be penetrating into the lounge. But you're right it probably does splash quite high up.

Dont let the guy come on Saturday, he will try to sell you an injected DPC whether you need it or not.

Get an independent building surveyor to inspect or a local builder.

Update awaited!

Update: so the damp is largely confined to the porch way and the guy said truthfully it doesnt matter too much there. He is a qualified RICS surveyor. He bay window walls dont have high damp levels so he doesnt need to do anything with that. The guy said if I wanted I could get the porch way rendered and mentioned pre grit, and some sand/mortar mix ratio to do that then skimming it.

But I do have damp on the internal walls where the entrance to the house is.

I also have a downstairs WC where this week I ripped off the skirting board but it was suffering from wet rot as that is an area of damp too.

Then theres the back kitchen wall to the left of the back door into the utility room (not really a room as such, more where the boiler is installed and my dryer is tucked in underneath it).

He took photos and will send me a PDF of the issues and the cost to resolve. Which includes dpc injections.

To add: I had a roofing contractor out today (different one to the chap who is meant to be coming next week). He has confirmed the main water ingress is coming from the chimney flashing.

He had quoted me 800 for capping the chimney, replacing new flashing and soakers, repointing ridge tiles and putting a stop cap on and sorting the gutter at the front.

The damp inspector checked my chimney at the bottom and that is dry as a bone. Most of my house is, its just the problem area with the porch, the WC and kitchen back wall on one side of the door.

"I also have a downstairs WC where this week I ripped off the skirting board but it was suffering from wet rot as that is an area of damp too."

Post some pics please. Might be a plumbing leak.

Pic of the WC. I can't see a leak. I've removed the crappy cover that houses the soil pipe on the RH side of the lav too but I can't see a leak.

The damp is remarkably close to the radiator pipe, the cistern and the soil pipe.

This might not be a coincidence.

Are other walls equally wet?

Looks like you have laminate flooring which hides any damp in the floor.

Thanks for your reply @PigletJohn

The laminate is on top of the tiles that were there when I moved in. My ex laid the laminate. The wall with the rad is dry. Its just the wall with the cistern on it which is wet. The wall under the stairs is dry when read with the meter.

There was a leaky pipe a number of years ago but my ex sorted that. The skirting has only just rotted within the past 12 months or so. It went all crumbly. I cant see any obvious signs of leaking

Heritage house site has good info on damp etc....rendering might just seal any damp in...could make it worse !

Ok.... so I looked on heritage house website and had a good read. My main take away is that apart from penetrating damp, most 'rising damp' is simply put, condensation.

I realise they talk about the use of lime mortar for pointing and lime plaster too. My question is - is this only relevant to solid walled property as opposed to cavity wall properties? @C4tastrophe @PigletJohn @Sanch1 do any of you know?

I need the pointing doing around and would be tempted to use lime mortar, but I dont know of that would be useless on cavity wall. I dont even know if the porch HAS a cavity wall like the rest of the house, although it is double skinned so why wouldn't it?

I switched the radiator off in the downstairs WC ages ago as didnt see the need to have it on. I'm wondering if that has some how contributed to the damp I'm seeing there.

Meant to day I need the pointing doing around the bottom of the porch*

Double skin is a cavity. Lime mortar allows permeability of moisture, so breathing.
Below a damp proof course, it’s damp anyway so you can use normal cement/wallcrete. Better off trying to stop water getting in rather than escaping. Above the DPC you can use lime, but for the porch I doubt it matters.
I’d run the radiator in the loo and check back in 3 or 4 months. I’ve seen cisterns on outside walls dripping condensation.
A couple of pics of the lower portion of the porch where the problem is would help, and the dodgy pointing.
Sounds like you need to get the roofer in first, then give it a while to see how things improve.

Lime mortar, and especially lime render, is often needed in Victorian and older houses. It was still being used up to about 1940, depending on local practice and size of job. If you have cavity walls I think your house is likely to have been built with cement, machine-pressed bricks, and gypsum plaster. Photos of the brickwork will help.