Old sandstone house - damp floor issues

Charlieepie

Hi all!

Wondering if I could have some advice RE flooring in an old property (surveyor reckoned constructed 1910-ish). Sorry for the super-long post.
We moved in a few months ago and have had an absolute mare with it, surveyors picked up nothing (thats what I get for a Homebuyer report rather than a full structural survey I guess..) and the previous owners managed to hide quite a lot! We moved in expecting it to be a quick decorate-the-bedrooms job and its turned into a nightmare. Previous owner seemed either oblivious to the issues or really, really bad at DIY...

One of the issues we have is with our ground floor and damp. We noticed a couple of rotten floorboards under a window in the living room and thought this was an isolated incident, but when we had a joiner round he pulled the carpets back and sawed the rotten floorboards out for replacement and we found the joists are also totally rotten. It looks like the original floor, the joists are laying on a what looks like a small wall built next to our outer house wall, with no damp-proof membrane underneath, just what I think is clay soil and about a 3 foot gap! His advice was to rip the wood floor out and lay concrete, as there are no air bricks and the floor level as it is isn't high enough to install them and have them ventilate to the outside - certainly when you walk down the street, the rest of the houses on the road have air bricks but they also have a substantial step up to their front doors that we don't have suggesting the floor level is higher than ours. The kitchen and entrance hallway floor are concrete too which won't help with ventilation.

And so the other issue - the concrete floor. We can't find any evidence of a damp issue in the kitchen, nor the cupboard under the stairs which is a pleasant surprise. However I've just had some of the vinyl covering back and its ever so slightly damp underneath. In the kitchen it doesn't seem to be causing any issues, though I haven't looked at the whole floor or behind the fitted units etc. However, I then pulled the carpet in the small entrance hallway up, and its very damp underneath, the wooden bits with nails in that you fix carpet underlay to (whatever its called) are all totally rotten, the underlay has cellar fungus all over it (pretty grim), and maybe the last 1/2 cm of the stairs, skirting and doorframes that touch the concrete are a bit rotten. The carpet looks pretty old so has probably been down a while though, and the rot is wet rot and hasn't spread any further than the bit immediately touching the concrete. I don't know why this bit of floor seems so much wetter than the bit I felt in the kitchen, though who knows, maybe most of the rest of the kitchen is the same and I lifted the vinyl on a dry bit! Also the kitchen and extension out back are the only bits of the house with a water supply so I don't think we have a burst pipe under the entrance hall.

Any advice on what to do? Do we fully investigate kitchen floor, lay an entirely new floor, etc etc? I was hoping to avoid a whole new floor, we also need a couple of roof repairs and every outside wall repointing which will set us back a decent amount. We didn't budget for much other than some painting and plastering when we moved in so this is quite painful. Is it worth getting a whole new floor laid for the small amount of problems the concrete is causing? Obviously we do, however, need a new floor in the living room - and the joiner recommended concrete, though I know from research now that concrete seems not to mix too well with old sandstone blocks, so anyone had any experience with limecrete?

We've got a builder coming over to look at living room floor and price replacement up, just want to know other opinions before we proceed with anything that may or may not be the right thing to do.

I have definitely learned from this experience what to look for next time I buy a house - this is mine and my boyfriend's first house and the issues definitely take the shine off it!

Doozergirl

Photos, please.

You need to find the source.

I'd specifically like to see your ground build up.

You also say that you have repointing issues and roof problems, so you have potential culprits there. The primary aim is to stop the ingress, not block it out as it will get up the walls when you concrete. Injected DPCs and rendering internally don't work, they disguise. Stop the water ingress, allow the house to breathe and then wait for it to dry.

Old houses don't respond well to having concrete floors so I would avoid that. The houses were built correctly; to breathe. The problems are caused by modern interventions in the form of bad building and DIY. Let's have a look at the house.

FreeBear

I know of at least a couple of people that have installed a limecrete floor - It involves quite a bit of work and you may struggle to find someone who can do the job. That said, if you are an ardent DIYer, it is something you could do yourself. A couple of links for you...
https://www.mikewye.co.uk/ - A good source of all things lime, and the guys can give you an honest opinion on limecrete floors.
http://www.periodproperty.co.uk/forum/viewforum.php?f=1 - A useful and knowledgeable bunch when it comes to old properties.


When you come to repoint your walls, use a lime mortar without any cement added.

Charlieepie

Thanks for your replies! I took some photos before I went to work this morning - excuse the mess, we have cats and their toys get everywhere!

http:// s1248.photobucket.com/user/Charlieepie/library/

They uploaded in a bit of a weird order, but I’ve taken photos of -

- the living room - the worst bits for damp flooring are under both windows where the wall is less thick, and the forward facing corners - the mortar on these bits seems noticeably bad. We’ve also got a stone hearth that seems damp under the carpet, but no other obvious problems in either chimney breasts in the house (if the chimney leaks I assumed we’d see problems somewhere other than the hearth). There’s also 2 pictures under the floor in there. The clay soil is wet to touch when you reach under, and the bricks that are lower than ground are wet. It’s rained a fair amount lately.

- the entrance hallway and whats underneath the carpet at the base of the stairs

- the kitchen, mostly covered by kitchen units though so not too helpful. The floors are concrete and the walls under the windows are thicker than in the living room, don’t know if it was built like this or whether they’ve had the walls built out when the floor was concreted. Extension floor is also concrete but not too concerned about this as it’s an 80s addition.

- the front door, which opens into the entrance bit where the concrete is the most damp, and the outside wall for one side of the living room. I think our floor must be an inch higher than the pavement level, if that. Couldn’t take any more of the outside as it was too dark!

Thanks for the pointer on lime mortar with the bricks, we’ve got a builder who does some national trust restorations in to do it spring/summer and he’ll be using lime mortar. We’ll then need to do a bit of restoration on our brickwork as some of the faces are crumbling a little, I’m assuming due to moisture content and freezing in the winter? But I think we can do this ourselves.

I’ll be looking into limecrete too, see if it’s something me, my other half and his dad can do between us!

Charlieepie

Just a pointer (don’t seem to be able to edit my post on my phone), the link needs a couple of spaces removed between http:// and s before it will load - as I am too new to post links.

Doozergirl

http://s1248.photobucket.com/user/Charlieepie/media/C6D50D9D-3EDD-464C-ADAC-2A1EC53A3294_zpspdhtdyfg.jpeg.html?sort=3&o=1

Thank you. I haven't got a proper chance to look through, but some more of outside - in daylight, would be helpful, and a shot of the whole house so we can see how the land lies and how your walls look.

It's outside that often provides the clues. I understand you're lacking air bricks but if the ground under the house is wet, then there's more to it.

Charlieepie

Have uploaded a few more of the outside of the house now it’s light ��.
Having had a nosy round whilst doing it, I’m a bit concerned at a little gap in the pavement, just behind the pavement channel, where some of our lower brick is exposed and I suppose water could pool in heavy rain.

Regarding water source - will the ground underneath not just become moist from drainage from other places when it rains? Or am I missing something? Any help appreciated.

Doozergirl

Oh my. Your house is half buried and there's nothing you can do to free it at pavement level. Probably something you can do at the back but it's clear to me from the proportions that any original DPCs are buried. You had a Homebuyers? It said NOTHING about damp?

You either tank it and move at some point before it the damp shows its face, or I'd ask Heritage Consulting to go in and give you some advice on how to deal with it with some sympathy to the house. https://www.heritage-consulting.org

Could you read through that survey again? I'm shocked that it mentions no risk of damp and no damp readings. I'd be persuing that route if it genuinely says nothing.

Doozergirl

Does your rainwater pipe even have a shoe pointing the water away from the house?

I can see why someone suggest concreting the floor (that's virtually unique for me) but the water will be pushed up the walls. It can't be treated properly with a chemical DPC or going one metre up the wall with render - nothing can, in honesty, but your house will breach it again.

You're virtually living in a cellar.

Please feedback with some more detail on the survey results.

Thanks for being so detailed

Charlieepie

Hi,

Thanks for replies. Yes the rainwater pipe points water away from the house - it didn’t when we moved in though, that’s something we fixed ourselves. Probably hard to see in that light as the pipe is black.

The survey mentioned that some meter readings had showed slight damp in the downstairs walls. However it’s previously had an injected DPC (I know now they are basically useless - however, we didn’t know much about old houses at the time), so the previous owners got the contractors out who drilled us some holes in the plaster and confirmed that the walls weren’t damp internally. Those damp proofing guys said the house isn’t damp and the moisture readings were probably condensation. The survey however did say the whole ground floor was made of solid construction so I’m a bit miffed they missed the wooden floor in the living room given that the rotten joists cause a noticeable bounce when you enter.

I don’t really know how to proceed, I don’t really want to bodge it, but we don’t have endless money available to sort it and damp floors downstairs is really pants so I would like to try and get to a point where it’s not going to send all my carpets and underlay mouldy. We weren’t planning on selling up for a while as we loved the house when we looked round but I can say now I wish we hadn’t bought it! We have friends that live a few doors down that haven’t reported problems, but then, they do have a step up to their house so maybe previous owner has had the floor raised. They also don’t seem as concerned as I am - their response to a small damp patch that came through their wall was to whack some damp proof paint on it which is the kind of thing I was hoping to avoid.

Charlieepie

I have also just had another nosy underfloor, thanks to the open floorboards... and have found a few cracked slate tiles. Would I be right in thinking these are likely part of the original DPC? If so, then the DPC is almost certainly a good portion lower than the pavement and road outside as these are all just below the level of the small ‘wall’ type thing our joists are resting on...