Pre-purchase survey finds damp!

[johnandrew]

Dear All

Have recently received the report of a structural survey on the stone built victorian house we are planning to buy.

I have my own ideas about how to go about things but wanted some reassurance from someone who has the experience that I don't have. Having failed to get that reassurance from the survey report, I am turning to you guys to give me the confidence that I am on the right lines.

Here we go then:

1.) The external ground levels seem a bit high (at or just below internal floor level). Some evidence of replaced ground floor joists in the timber suspended floor.

Surveyor says: There are air bricks but they give inadequate flow and are below ground level. They need to be replaced with modern ones and moved higher so they are not at ground level.

I say: Maybe more airbricks/vent are need but surely they don't need to be moved up. The ground level needs to be moved down.


2.) Pointing

Surveyor says: Evidence of repointing to some of the property in sand and cement. Original pointing also done with sand and cement

I say: Given the surveyor estimates the construction date to be 1860-1880 is it not likely that the original mortar is a sand and lime?

3.) Dampness (maybe you can all guess what is coming now)

Surveryor says: The walls were tested with a meter at ground level and we received very high readings. We think this is because of rising dampness and the lack of any apparent DPC. Advise you to get in member of BWPDPA to investigate further.

I say: Indeed there is dampness. The place smells musty, the paper is peeling from the walls, the plaster is all but hanging off. But, perhaps the DPC is hidden by the raised ground levels? Even if there isn't one, maybe we should consider reducing exterior ground levels, opening the fireplace, and ventilating the place.

Won't go on any more.

So, am I on the right track?

Thanks

John Andrew

 

[Jon Maine]

Not far wrong at all I would say, just dont go undermining your foundations when you dig away!!

You could also take up some floorboards, inspect the joists and if needed clear back debris from below the floor and against the wall too.

Check rainwater goods and outlets including the drains they run into. Make sure you are removing excess dampness from the area. Just check the way the land lies and drains.

Of course if he is only advising you ok, Is he advising your mortgage co.?

If so they may not be so pragmatic.

 

[Penners]

The recommendation to move the airbrick(s) higher up the wall is a strange one. The whole function of these is to create ventilation underneath the suspended floor. I agree with your assessment - if external soil is blocking the airbricks, lower the soil. And, as you say, external soil levels should generally be at least 15cm below internal floor levels.

 

[Lime]

Spot on I'd say johnandrew.

 

[Flyfisher]

Our cellar airbricks were blocked and the cellar had that old, damp and musty smell to it. Although below ground level, the airbricks/grilles were surrounded by bricks to keep away the earth, a bit like a drain really (not very easy to describe). It was this 'drain' that had become clogged with general detritus and was easily cleared, allowing free airflow to the airbricks/grilles into the cellar. 18 months on the musty smell no longer pervades the cellar. Depending on your circumstances, this might be an easier solution than lowering the ground level.

 

[Penners]

Although if the ground level is at, or only slightly below, internal floors, then it should be lowered anyway.

 

[middi]

Reduce the external ground floor to below air brick level
Make sure the air bricks are clear and free of debris
Insert some more air bricks if necessary ( or just do it, anyway)
Check the existing floor joists for damage ( rot) and repair as required
Unless you can move the internal floor level higher than the existing outside ground level ( this will, most likely, not be practical at all), I don't see the futile exercise of installing air bricks further up the wall.

It sounds like your surveyor had a bad day at the office, or, had just come out of the local pub.

 

[johnandrew]

Yes, I agree. The surveyor must have had a bad day.

It's rather disappointing though, as I got their contact details from PPUK web site and their own web site states that they have experience of working sympathetically with old buildings.. I also specifically spoke to the surveyor about my desire to use lime and other crazy stuff and not to be simply told "it's damp, go see the DWPDPA" .

Oh well.

Cheers

JA

 

[Flyfisher]

Although if the ground level is at, or only slightly below, internal floors, then it should be lowered anyway.

Yes, but I would have thought it quite common for cellar air vents to be below the external ground level even though the floor (not the cellar floor) is above ground level, hence the 'drain' type arrangement I mentioned to keep the ground soil away from the cellar vent. Having said that, I'm only guessing this is a common arrangement - perhaps our house is unusual in this respect.

 

[Nemesis]

No, some of our underfloor vents are like that, no cellar, just underfloor ventilation.

 

[Lime]

All of the airbricks in "drain-like" holes that I have seen and/or investigated have all started out life above ground.
As the surrounding earth/land level has built up so the air brick approached ground level, then below.
Sometimes this is "helped" by man i.e. paths and roads being made up next to the wall or simple earthworm activity.

After all the romans didn't bury themselves, it wos time that dun it.

 

[Nemesis]

No, ours are built like that, carefully constructed 'chutes' in the stone.

 

[Lime]

Yes, that is so.
However I was referring to the

Although below ground level, the airbricks/grilles were surrounded by bricks to keep away the earth, a bit like a drain really (not very easy to describe). It was this 'drain' that had become clogged with general detritus and was easily cleared, allowing free airflow to the airbricks/grilles into the cellar.

 

[Nemesis]

Well, ours are surrounded by bricks too, as the grilles are below ground level with a space built around, and small brick 'walls' built on top to prevent water getting in.

 

[dalivar]

Hello, and sorry for butting in on this thread, but it's a very similar situation to the one I am in and I'd really appreciate some input as my mind is racing trying to decide what to do for the best.
We also are purchasing a Victorian stone property which has also been surveyed and found to have damp. The damp survey suggests lowering outside ground levels, which seems reasonable and also injecting a DPC which does not... The solid ground floor appears to have been laid over with concrete and asphalt and the outside walls are rendered with cement. There is no mention of these being a problem in the survey. So, should we just look for another surveyor with historic building experience?

We haven't paid the mortgage valuation fee yet as we wanted to find out the cause of the damp first. What if their surveyor tells us to inject a DPC? Can we argue the point? I'm starting to worry as we made our offer in August and its dragging on a bit.. Am I being too cautious!?
Please help!

 

[mivec]

....................................................................................................

 

[Lime]

dalivar, I think you already know what the problem is.
The difficulty will be explaining that to your mortgage lender.
All the points you make are relevant and I agree with them and with your concerns.
I assume the damp survey was instigated by you?
It may be beneficial to go back to them and state your concerns.
If they don't agree then find another surveyor with historic building experience, who is sympathetic to and understands older designs.

 

[stuart45]

Having worked in the building trade since leaving school in the 60's I would say that the biggest con in the trade has been the sale of chemical DPC's for problems with rising damp due to failed or missing DPC's. Wall tie replacement is now starting to catch up though.

 

[88v8]

Hello, and sorry for butting in on this thread, but it's a very similar situation to the one I am in and I'd really appreciate some input as my mind is racing trying to decide what to do for the best.
We also are purchasing a Victorian stone property which has also been surveyed and found to have damp. The damp survey suggests lowering outside ground levels, which seems reasonable and also injecting a DPC which does not... The solid ground floor appears to have been laid over with concrete and asphalt and the outside walls are rendered with cement. There is no mention of these being a problem in the survey. So, should we just look for another surveyor with historic building experience?

We haven't paid the mortgage valuation fee yet as we wanted to find out the cause of the damp first. What if their surveyor tells us to inject a DPC? Can we argue the point? I'm starting to worry as we made our offer in August and its dragging on a bit.. Am I being too cautious!?
Please help!

Well it is a fairly ancient thread, but perhaps better to have started a new one.
Anyway, welcome to the Damp and Other Things Forum

Yes, concrete, asphalt, cement, are all potential problems...
There may already be a perfectly good dpc, or if the concrete etc is removed it may not need one depending on the construction & design of the original house.
I would indeed look for another surveyor. Where are you?

Ivor

 

[dalivar]

Thanks Lime, stuart and 88v8,
rookie error - i missed the second page, so sorry for the late response.

We have found a decent surveyor now but decided to wait, and go ahead and get the valuation survey done. If they say something silly then we will get the historic surveyor to come out and hope they can help us make our point heard.
We arranged a building survey first - he mentioned damp so we got damp survey done too. I wish we'd known to look for a historic specialist at the outset - he could have done all this in one visit without costing so much!
We decided we want this house with its faults and aim to repair/replace what we can do sensibly in time.
BTW we are in North Wales.

Cheers
D.