Another tedious damp problem!

[Flyfisher]

Soakaway info: http://www.waveney.gov.uk/Planning/Bldng+Control/Guidance+Documents/soakaway_guidance.htm

Google "soakaway" for loads more.

 

[jaykayem]

Soakaway info: http://www.waveney.gov.uk/Planning/Bldng+Control/Guidance+Documents/soakaway_guidance.htm

Google "soakaway" for loads more.

Thanks for this, will stop being lazy and do some research on soakaways! If a rain butt isn't the answer I need to sort this out.

As for the hygroscopic damp, there are lots of salt deposits on the external wall (both in the mortar and brick) but I can't really detect any inside yet. Not sure what that means.

As for thr ground level, I've just checked it and thereis virtually no difference between the external and internal level. Is this bad for rising damp and hygroscopic damp? I can't really raise the level of the internal floor as the beams are too low. I think there is only one level where the plaster has shown signs of this being a problem, and i will post a photo. Woul repointing with blue bricks help? If I explain that my partner and I are expecting a new arrival in the new year, and we're aiming to sell the following spring, is there a way that I can get the house saleable without compounding the problem for the future owners?

P.S. Flyfisher, by "rotten day", I meant the weather, which was horrendous!

 

[Flyfisher]

P.S. Flyfisher, by "rotten day", I meant the weather, which was horrendous!

I've found it quite interesting* and productive to walk around the outside of our house (and scaffolding) during rain storms and really see how the rainwater is being handled. I've spotted, and easily fixed, a number of problems that were only really obvious when it was pouring with rain.

Regarding ground levels being the same as internal floor levels, this seems to be fairly common with old properties. A 'French drain' is the answer, which is basically a shallow trench dug around the outside wall of the property. I've not yet tried this myself, but it's on my list of things to do. Again, lots of info about them on the web but this is a good introduction: http://www.spab.org.uk/html/advice/technical-qas/technical-qa-19-french-drains/

*How sad is that?

 

[JoceAndChris]

*How sad is that?

No, no, it's those who don't find this kind of thing utterly absorbing who are the sad ones.

I've got a new mania for measuring my well and seeing to what extent the depth mirrors rainfall patterns. This weekend we have 14 guests staying, we're going to switch off the rainwater entirely, and measure the before and after effects on the well. I'm beyond excited.

It's also very interesting to take note of fluctuating damp problems according to the seasons and weather. For example, when there are high levels of heat and humidity, my pamments sweat and are covered in minute beads of water. Yet now during this very wet weather they're entirely dry.

Water is as fascinating as fire.

I need to make French drains too, I'm dreading it. Gawd knows what we'll find when we dig down.

 

[philpjuk100]

When digging NEVER look at anything you have dug,it only slows the job down.Was going to plant some seed spuds a few weeks back,the first spade full had a musket ball in and the second had a sort of pike end thing in it,got out metal detector,detected lots of other bits of metal,cleaned them up,reasearched them on the internet,the spuds?they are still on top of the coal bunker! phil.

 

[CHRIS]

Much more info is available on this site

http://www.pavingexpert.com/drain08.html

 

[Lime]

I don't think it has been said, so I'll say it.
Lowering the outside ground level is far better than installing french drains.

However, stop rain entering the property from the roof first.
Make sure that any water outside the house drains away from the property.. a gentle slope will do the trick.
Don't have flowerbeds built up against the house either.

If you want to sell the property next year but one this work needs to be done very soon as the wall will take some while to dry.
Forced drying is not recommended. Far better to have a good flow of ventilation to the room all the time while the wall dries.
Don't have anything (cupboards, piles of books, paving stones.. anything that will stop air circulation) against the damp walls either.

 

[Flyfisher]

I don't think it has been said, so I'll say it.
Lowering the outside ground level is far better than installing french drains.

Fair point. I probably wasn't using the term in an entirely correct way as I'm not really sure when a 'ditch' dug around the house to ventilate the lower wall actually becomes a french drain. When it's filled with gravel and a land-drain pipe perhaps?

Parts of our house require the ground level lowering but it's not really practical to lower the gardens for many yards back from the house, so I'm planning to dig a trench about 12-18 wide and as deep as required to get the ground level below the inside floor level. The issue I've not really resolved yet is how to 'dress up' the trench? I presume leaving it open would be best for ventilation but it would require regular cleaning to prevent it silting up over time. Filling with coarse gravel would make it very free-draining but would also retain a fair amount of moisture. I've even though about some sort of 'grille' , which might help keep it clear (although not eliminate the need for regular clean-outs) but, apart from the expense, I don't think it would look particularly good.

Any suggestions?

 

[CHRIS]

Filling with coarse gravel would make it very free-draining but would also retain a fair amount of moisture. I've even though about some sort of 'grille' , which might help keep it clear (although not eliminate the need for regular clean-outs) but, apart from the expense, I don't think it would look particularly good.

I am not sure if this is what you are looking at but I use these type of things a lot of the time for land drainage.

http://www.geotechnics-uk.com/

http://www.aco-technologies.com/

I bet you can get some plastic egg crate type thing and hide it with some planters or pots etc. I have seen it with a filter type of paving stone (the type people have to use if the want to park on their front gardens now). I may look a bit "NEW" but if you hunted around you may find something.

 

[Flyfisher]

That's not really the sort of thing I had in mind, although coincidentally, I could use it somewhere else.

Any trench around most of our house would not really be a drain as such because of the roof overhang and the land slopes gently away anyway, no I doubt there would be much water collecting in it. It would be primarily just to make the outside ground level lower than the inside floor and allow good ventilation to the bottom of the walls and, for half the house, the oak sole plates (assuming they are still there when I dig down ).

So the idea of the grille was just to stop people slipping into the trench and breaking an ankle. Still, I've got enough time to reconsider the landscaping possibilities before I eventually get out the spade. The planters/pots idea might work in places.

 

[Lime]

Nothing beats "thin air" for good ventilation in a ditch around the house.
Stones or anything else that prevents evaporation will keep the ditch wet.
Also stones become compacted/filled up with soil remarkably quickly.
In the olden days (victorian particularly) a blacksmith might have been asked to construct a small set of railings built in the shape of a quadrant to sit over the ditch.

 

[Flyfisher]

In the olden days (victorian particularly) a blacksmith might have been asked to construct a small set of railings built in the shape of a quadrant to sit over the ditch.

That sounds more like it, although I'm not entirely sure of the design you described; I can't see railings sitting over a ditch. But I like the general idea. I bet it would be an expensive job these days though. I should look for a local blacksmith, perhaps, and make some enquiries.

 

[Ushy M]

The issue I've not really resolved yet is how to 'dress up' the trench? I presume leaving it open would be best for ventilation but it would require regular cleaning to prevent it silting up over time. Filling with coarse gravel would make it very free-draining but would also retain a fair amount of moisture.

Lime is of course right that leaving it open will create most airflow. This wasn't practical in our case, as we had to make a french drain in the churchyard where the gable end of the house is. We lined the hole with geotex, put gravel in the bottom, laid a perforated land drain on top, filled the trench with 100mm+ beach cobbles, wrapped the geotex over the top and finished with a layer of pebbles so it looked OK in the churchyard. The geotex helps to stop silt filling up the trench and the biggish cobbles allow some air circulation and crucuially don't absorb moisture themselves. Hope this helps.

 

[Gareth Hughes]

In the olden days (victorian particularly) a blacksmith might have been asked to construct a small set of railings built in the shape of a quadrant to sit over the ditch.

That sounds more like it, although I'm not entirely sure of the design you described; I can't see railings sitting over a ditch. But I like the general idea. I bet it would be an expensive job these days though. I should look for a local blacksmith, perhaps, and make some enquiries.

I may be wrong, but possibly something of this sort was meant:

 

[Flyfisher]

Thanks for that Gareth (is that your own sketch?). I think that sort of thing would be a bit too intrusive though (would it require LBC I wonder?).
I was thinking more of something flat.

 

[Penners]

I was thinking more of something flat.

The problem, as Lime has observed, is that anything you put over the trench carries the risk of reducing the circulation of air, which is vital to its proper functioning as a damp cpntrol measure.

OK, a fine mesh of some sort would not affect airflow to any appreciable extent, but once you start talking in terms of grilles (by which I imagine you mean something vaguely like the image below), I suspect the affect on airflow could be enough to matter.

 

[Lime]

The sketch posted by Gareth Hughes depicts the type of railing precisely.

 

[Gareth Hughes]

Thanks for that Gareth (is that your own sketch?). I think that sort of thing would be a bit too intrusive though (would it require LBC I wonder?).
I was thinking more of something flat.

I think my sketch exaggerates the size of it in relation to the building, a bit at least.

 

[Gareth Hughes]

Just to sound a note of caution - Archaeologists of my acquaintance might have qualms about unrestrained digging of French drains on possibly sensitive sights (and having seen the damage just a 6" by 9" water pipe trench did to shallowly-buried Elizabethan remains, I can understand their concerns).

 

[Penners]

I think my sketch exaggerates the size

In which case I think I may have seen some of your sketches on toilet walls.