Been quoted over £34,000 to fix damp problems in a house I'm thinking of buying

[Dan24]

FTB here would really appreciate some advice!

Thinking of buying a Victorian end of Terrace. The couple we're buying it from have lived there for over 40 years.

It has issues with rising and penetrating damp.

Had an independent damp survey (not attached to a damp proofing company) which said:

"Majority of the damp issues are caused by high ground level and condensation due to the house constructed with a through-stone construction which also appears to have been contributed to by penetrating damp and condensation from the missing pointing/spalling stone and high external ground level along the gable and rear. The damp to the internal walls between the living room and hall and the kitchen and dining room are likely to be caused by damp from the wall to floor junction of the solid floors."

The damp report then recommended the following:

1. Repointing the property with lime (current reporting is cement-based) £14,000
2. Cavity drainage membranes which will involve replastering £15,000
3. New kitchen (has to be done to get the cavity drainage membranes added) £5000
   
   Damp report didn't mention that there was a gully to the rear of the property, which to me I feel should help with some of the low ground level issues. I did notice it was full of vegetation and could do with a clearout.

I have heard a lot of people talking about Pete Ward's theory and looking at the drain's and improving ventilation (the property has no ventilation in kitchen or bathroom and some of the drains have vegetation and one of the airbricks is damaged) am I naive in thinking that more ventilation and clearing the gutters & drains could solve the worst of this or does this seem like a nightmare property and I'm being idealistic?

I am currently getting £24k (or 8% off the asking price, which seemed reasonably priced if the house had 0 issues)

Link to photos of property:

https://imgur.com/a/qmaWibf

 

[opps]

I am not able to comment on the requisite work, but, having owned a damp meter in the past, I soon discovered that they are prone to giving false positives. They are great for checking moisture levels in timber, but when it comes to plaster... Plaster that has previously become wet because of a leak/etc will flag as being damp when using a damp meter even when it is perfectly dry.

 

[paulg22]

£14k seems very expensive for repointing!

I had lime pointing done on my last house a couple of years ago: a 1920s stone-built semi. It was only the side (single storey) and the back (two storey) that I had done, but it cost a shade over £3k and took him just over a week to do.

 

[JohnD]

Yes, you should start by identifying and repairing the defects causing the damp..

If a major cause is ground level too high against the walls

then presumably reducing the ground level against the walls would be one of the first things to do.

Are the ground floors concrete, or are they suspended timber floors with a void beneath, ventilated with air bricks?

I am pleased to see they do not mention silicone injections, which are a complete waste of money and do not repair the faults.

How old is the house?

Are the neighbours' houses damp?

Are there leaks from drains, plumbing or gutters? The external pics appear to show black stains running down the walls where rainwater from the roof runs down.

 

[blup]

Can't access the pics but aren't cavity membranes are associated with protecting cellars? If the outside bridges the dpc the normal approach is to remove it to 150mm below. Re lime plaster, skill builders on YT did an experiment which suggested ordinary mortar suffices for repointing in many cases. You will need to check the condition of the floors re damp ingress and check the drains. Plastering can be reviewed after you have corrected the source of tne damp. You might be getting a bargain if you have got the price reduced by 24k based the damp proof survey.

 

[Dan24]

£14k seems very expensive for repointing!

I had lime pointing done on my last house a couple of years ago: a 1920s stone-built semi. It was only the side (single storey) and the back (two storey) that I had done, but it cost a shade over £3k and took him just over a week to do.

Yeah, it does seem a lot doesn't it? I've had quotes for less money, but lowest is £8k

Did your costing involve ripping out all the old pointing, doing all the new repointing and paying for Scaffolding?

 

[Dan24]

Yes, you should start by identifying and repairing the defects causing the damp..

If a major cause is ground level too high against the walls

then presumably reducing the ground level against the walls would be one of the first things to do.

Are the ground floors concrete, or are they suspended timber floors with a void beneath, ventilated with air bricks?

I am pleased to see they do not mention silicone injections, which are a complete waste of money and do not repair the faults.

How old is the house?

Are the neighbours' houses damp?

Are there leaks from drains, plumbing or gutters? The external pics appear to show black stains running down the walls where rainwater from the roof runs down.

Thanks for your reply,

the issue is the ground level on the gable wall is a public footpath so reducing it isn't possible. I was surprised the high ground level would be relevant because it's a steep hill so I figured the water would just run down the hill and not pool against the wall but I've been told high ground level is the cause

The ground floors are suspended timber floors with a void beneath ventilated with airbricks and as the property rises there is a step within the property to help account for some of the raised ground levels when you move from the lower half to the higher half

The house was built around 1850 (I think)

Not sure if neighbours houses are damp

There was an issue with the chimeny leaking which was fixed a few months ago. The surveyor also believes there is leaking coming from the bathroom area. I'm not sure if there are leaks from drains, plumbing or gutters but the property surveyor noticed signs of undulation to the roof which concerned him so we got out a structural engineer who had no concern with the roof.

 

[Dan24]

Can't access the pics but aren't cavity membranes are associated with protecting cellars? If the outside bridges the dpc the normal approach is to remove it to 150mm below. Re lime plaster, skill builders on YT did an experiment which suggested ordinary mortar suffices for repointing in many cases. You will need to check the condition of the floors re damp ingress and check the drains. Plastering can be reviewed after you have corrected the source of tne damp. You might be getting a bargain if you have got the price reduced by 24k based the damp proof survey.

Thanks, the problem we have is that the gable wall with the heightened ground elevation is on a public-facing road so we can't lower the ground level. Although internally there is a step for the higher part of the house which helps mitigate the ground level a little. What I don't understand is because the hill is so steep, why this would create damp because surely the water would travel down the street as opposed to pool next to the property and none of the bricks at ground level look spalled or damaged, what do you think?

 

[blup]

I can’t open the pics but it sounds like the damp in the soil is directly penetrating the wall, it’s not just about free flowing water

 

[Dan24]

I can’t open the pics but it sounds like the damp in the soil is directly penetrating the wall, it’s not just about free flowing water

I know the water and sewage mains run through the garden, do you think a CCTV drainage scan might be useful?

 

[JohnD]

Cavity membrane is used in basements, when you have water coming through a wall and can't stop it. The idea is that water is allowed to run down the wall behind the membrane, into a gutter or trough whence it is drained or pumped away. In these cases a false floor is also used so that water coming through the floor can also be taken away without grtting into the habitable space or structure, and there is a false wall on the dry side. The floor and walls on the outside of the membrane will be permanently wet.

AFAIK it is not common in UK except for basement conversions and you would need to find a contractor who could show he was trained in the method and preferably approved by the system manufacturer. This might explain the high cost. I would be very cautious of a jobbing local builder.

The council might give permission to trench the pavement and add waterproofing to the wall and a French Drain or something. It would be no more disruptive than laying a pipe or cable, which happens every day. Damp will still rise up the wall from the foundations until it reaches the DPC. You should inspect all drains and pipes and rectify while working.

Avoid silicone injections which are useless.

 

[HERTS P&D]

do you think a CCTV drainage scan might be useful?

Always!

Andy

 

[Dan24]

Cavity membrane is used in basements, when you have water coming through a wall and can't stop it. The idea is that water is allowed to run down the wall behind the membrane, into a gutter or trough whence it is drained or pumped away. In these cases a false floor is also used so that water coming through the floor can also be taken away without grtting into the habitable space or structure. The floor and walls on the outside of the membrane will be permanently wet.

AFAIK it us not common in UK except for basement conversions and you would need to find a contractor who could show he was trained in the method and preferably approved by the system manufacturer. This might explain the high cost. I would be very cautious of a jobbing local builder.

Thanks, that makes sense

I was really surprised with the membrane suggestion as the pavement is only 4 bricks higher than the exterior road and it's a steep hill so I figured the water would run away from the property and not pool against the side. The bricks on the ground floor level all look fine too.

I'm also thinking of getting a CCTV drain survey because the water and sewage pipes run under the garden. I wonder if that could be the cause?

 

[JohnD]

P.s.

Test your waterpipe for leakage as well.

At a hundred years old it need to be replaced in larger plastic pipe all the way to the watermain in the street.

Is there a meter?

See updates to my earlier post.

 

[Dan24]

P.s.

Test your waterpipe for leakage as well.

At a hundred years old it need to be replaced in larger plastic pipe all the way to the watermain in the street.

Is there a meter?

See updates to my earlier post.

I'm not aware of there being a water meter, great shout on testing the water pipe, I'll look into doing that and seeing if I can trench the pavement too