1890's End Terrace House, damp and floor issues has stopped the house sale

[HollaHolland]

Hi, I've been following a few threads on here with interest as I have similar issues with my 1890's victorian end terraced house. It would be great to get some help fixing some issues I'm having.

As some background, I've recently tried to sell the house, but the building surveyor noted potential damp to chimney breasts, damp to most internal walls, repointing needed to exterior walls, spalled bricks, chimney pot not capped, raised external levels etc. The buyer has walked away. The surveyor actually gave a £0 valuation which I find unbelievable and obviously scared the buyer and the mortgage lender - it suggests the house is falling down! To point out for the 'damp' he used a protimeter - and having read up a lot about them I question the accuracy when used in plaster. That said I'm aware there are some things that need fixing such as the roofing items and raised external levels. We've taken the house off the market and want to sort the issues this year before the winter period hits ideally.

The house is solid wall construction. The living room and hallway are suspended construction and the dining room and kitchen at the back of the house are solid floor. There is a slate damp proof course to the walls. There is a modern dpc to the bay window which has been added later. I've provided a plan below pointing out these details.

The house has previously had damp proof course injected in 1996. It's 'technically' still under warranty as lasts for 30 years, however the company seems to have been dissolved so likely no recourse there. Having read lots of articles about the injected dpc it doesn't seem to be relevant anyway and may have done more harm than good.

The only evidence of damp is slightly discoloured paint to the external walls facing the alleyway and around one of the chimney breasts. There is some bubbling paint to some of these areas. There is no smell or any other indication of damp. There are no tide marks etc. We are careful with ventilating the rooms, keeping windows on vent at all times in the spring, summer, autumn (and open fully when possible), and then using a high performance dehumidifier during the winter in the dining room / living room.

I think the discoloured paint / bubbling as below might be from salts in the bricks coming through and disturbing the paint? It's about 1.5m up the wall.


I need to carry out some more investigations into the sub floor timbers to see what the current situation is, but when I had the floor boards up 5 years ago there was no sign of any rot or damp that I could see. I strengthened the floor using treated timber propped onto some of the dwarf walls, with a run of 300mm wide dpc underneath the timber. This has helped the situation whilst I've lived there and has stopped most of the 'springing' and 'bouncing', but the surveyor has put down his trusty spirit level and noted there is a cross fall in the floor towards the external wall, and recommended a damp and timber survey.

Proposed works I'm planning:

• cap open chimney pot with ventilated clay cap and seal against chimney pot
• relay the slabs lower to the front of the house so 50mm clear of underside of 3nr air bricks in the bay window. I might need to use a slab on edge detail with stone fill soakaway detail as the levels are require challenging here.
• replace air bricks with new ones to front elevation (I think the current ones are likely to be ruined when the previous owner laid the slabs and used concrete around the perimeter).
• try and connect the surface water downpipe into the drainage network. There's no evidence of a connection beneath the slabs, but all of the neighbours drain into a system so hopefully with some investigation this can be found. The downpipe is currently routed onto the path beyond the front garden wall.
• install 2nr air bricks to side elevation in the alley way. 1 either side of the chimney breast.
• repoint side of house where pointing has become weathered.
• replace weathered and spalled bricks.
• potentially remove tarmac in the alley, lower levels and install central paving slab with a stone margin to the sides to help drainage against the house below the dpc - see note about rights below.
• investigate sub floor timbers in living room.

Does anyone have any advice regarding ownership and rights for the alleyway between the houses? My deed plan does not include this area, neither does the neighbours. I think it is likely this is Council land. Are there any rights I have to make the Council lower the land if it causing damp and drainage issues to my property? If I choose to do this work myself do I need any consent from the Council, is this effectively likely to cause a legal issue?




Do the proposed works sound sensible and likely to be successful?

Apologies this is a lengthy first post!!....





Capping to chimney required.


front garden bay window


partially blocked air vents to front bay window


side alley (damp spots where the chimney stacks are?)


Spalled bricks and repointing needed


timbers in 2018, with what looks like suitable void of circa 500mm.



timbers in 2018, with what looks like suitable void of circa 500mm.

 

[Cubist]

Moisture meters can be affected by so many factors and the information they provide should always be regarded with suspicion. You don't say when the survey was done but given how much cool wet weather we've all seen these last couple of months... need I say more. My personal view is that these tools should only be used to take many observations over a sufficiently lengthy period to get a 'representative' view - but even then the result should be taken with a pinch of salt.

You have developed a very comprehensive plan of action that seems to me to hit all the important issues and the only thing I can think to suggest - given how much work you feel needs to be done - is to set and focus on the key priorities. Certainly concentrating on the external work that will in turn depend on good weather and/or the availability of tradespeople and their equipment would be key I think. Beyond that I can only suggest that you acquire a cheap damp meter, not to combat the report you've received, but for your use to monitor the efficacy of the works completed to ensure that the trend is heading in the right direction.

 

[HollaHolland]

Thanks for your reply Cubist - sounds like I'm on the right track!

I agree about prioritising the works and managing the costs - the roofing works will be first in the next few weeks, followed by lowering the front garden levels and sorting the air bricks, followed by pointing to external walls / spalled bricks etc. I'll look at the sub floor timbers in the meantime - hopefully they haven't deteriorated over the past 5 or so years.

Do you think the air bricks are necessary in the alley or is this a bit overkill? I'm not sure how helpful they would be to give cross ventilation.

Good idea about buying a protimeter, I think this will be a good investment to see the trend over time.

Thanks

 

[malcolm]

Sounds like a plan. Air bricks should be open and above exterior ground level so they can do underfloor venting without letting water in. It's normally a bad plan to get rid of any of them. Though looks dry under there at the moment.

Using a damp meter to detect damp that is not otherwise apparent is nonsense. Those things are only designed for wood and will pick up salts in an otherwise dry wall. Actually using the damp meter is a wall where damp is apparent is also nonsense as you can see there is damp there.

The alley is unlikely to be council owned unless it is a public footpath. More likely shared between you and the neighbours. Just knock on the neighbour's door and say you are having trouble selling your house because the alley is too high. They ought to be happy for you to lower it as it will get rid of similar problems for them. Level wants to be a couple of bricks below internal floor level.

The bricks will have weathered because of the cement pointing. It's well worth doing the lower part of the wall in lime. That lets water evaporate away from the wall so you don't get any damp inside or the salts on the external bricks.

Pepper pot chimney cap just sits on top. It doesn't need sealing to the chimney pot.

 

[Lacan07]

Your not the first person to visit this site complaining about an over zealous surveyor scuppering a sale. I would argue you've been unlucky. Your property is as common as muck in most towns and cities around the country (in a good way). Every time I'm out and about I'm always looking at old houses and the first thing I always clock is the high external ground, the spalled bricks, the lack of air bricks, the dreadful repointing and my personal favourite - the ubiquitous white emulsion all over paint job. Just about the worst thing you can do to an old house.