What do I need to fill cracks in the outside wall

PaulStat

PaulStat

PaulStat

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Cotham, Bristol
The render on the outside patio wall is cracking, and if you tap it you can hear the render is coming away from the wall. What do I need to fill the cracks?

DIY people help!

Youtube vid to help, sorry about the crackling, you might have to turn up your speakers to hear me speak, I'm quite quiet! :p

 
PaulStat said:
The render on the outside patio wall is cracking, and if you tap it you can hear the render is coming away from the wall. What do I need to fill the cracks?
Click to expand...

If the render is coming away from the walls, filling in the cracks will be a waste of time, effort and money.
 
I believe from the evidence shown that what the building may well be suffering from problems relating to damp, and (to a far lesser extent but still relevant up top near the road) vibration.

You may well be able to fill in the cracks and repaint, but I believe the rendering is coming away fairly seriously (and is showing clear symptoms of something rather more serious, that being damp). Therefore filling it may only serve temporarily. If you're a tenant or homeowner you will want to consider the options open to yourself accordingly. Without a doubt or too much delay I would get an independant appraisal from a qualified structural surveyor of which your landlord (if applicable) should be willing to make a contribution or pay outright. Incidentally if you have any children or visiting friends have any children with them, I'd probably keep the kids away from any kind of ball games. It does appear that the rendering is coming adrift in relatively large sections and looks like it could fall as a result of any significant impacts against it (reference the lower walls to the property itself, not those away or toward the road/path up top).

If you are a tenant and don't plan on staying there for more than a couple more years then go for the filling option. But do this in a considered manner, because what that will not address is the possibility of sections of render still falling away in future. So I should stress therefore that there will remain a risk to anyone in the area particularly kids.

If you own the property, get the surveyor in (may be a fee of roughly £60 - £120) for an hour or two to asses the extent of the damp, and the nature of the damp ingress. It will be either rising or penetrative, or fairly likely a ratio of both. The fix will I'm afraid be likely quite expensive because remedial work has not only to be carried out on the damp proof course of the property but probably also to the yard and property drainage (which in the case here is likely to run underground). I couldn't give any exact figures at all other than to say you will be looking at four figure sums at least, possibly five figure sums. Hence we need professionals to assess prior to remedial work taking place.

I'm sorry if this comes as any shock and personally I do hope you are just a tenant (because the remedial work won't be your bill to worry about, but you may be asked to pay a small percentage - depends largely upon your contract). If this is your property, your one recourse to saving some money might be if you have not owned to house for so long (less than six months approx) in which case you could fall back to the terms of sale and query the descriptions and legal assessments made when the proprty was valued beforehand. At this point don't waste money on any filler until you have that assessment carried out, or your landlord does. And keep kids away from it etc.

Keep us posted mate.

Just so you know where I'm coming from, I used to be an architectural designer. My father was a Danish architect. My ex-employers were: Mike Pert (F.I.P.D)
http://www.yell.com/listings/DoFindListings/3734672/Michael-R-Pert-F.I.P.D/Architectural-Services

And Robert Lord Associates, Barn 3, Flaxmans Farm, Felbrigg Road, Roughton, Norwich (no web reference)

My name is Jan Mathiesen.
 
Yikes^^, umm well re the damp the walls have been treated for damp proofing and if you look at the walls in the video you'll see evidence of this (the little grey circles where they've injected their stuff). We've owned the property for coming up to two years now so we did have a survey done at the time, and we still have the damp proofing certificate which is still valid for some time to come.

One thing I will say is there's no evidence of any damp inside the flat.
 
PaulStat said:
Yikes^^, umm well re the damp the walls have been treated for damp proofing and if you look at the walls in the video you'll see evidence of this (the little grey circles where they've injected their stuff). We've owned the property for coming up to two years now so we did have a survey done at the time, and we still have the damp proofing certificate which is still valid for some time to come.

One thing I will say is there's no evidence of any damp inside the flat.
Click to expand...

Ok cool. I see that and duly noted, thanks. What I was addressing was not the walls ability to resist water which is what the treatment probably addressed but in particular the permeation of water up the walls from the floor as a result of a defective DPC and/or drainage.

It could well be just a case of drainage causing the problems because basically were below ground level (are we on a hill?) and therefore the floor in the yard is probably below the local mean water table level. That's all my friend. The last thing I would want to see is any nasty or unforseen suprizes coming your way hence my enthusiasm to cover the bases a bit.

If I was closer to you I would come and have a look myself, but I am not qualified in the structurals so all I could ever do is make recommendations etc.
Any which way I would still highly recommend an qualified assessment. I know it's a pain, but as is the good old formula of life - action now will more than likley save money in the longer term ;)
 
And: :)

If it does indeed turn out to be just a drainage issue, then the nature of the damp ingress is more than likley just permeating (ie: rainfall, runoff etc etc). The render could do well to at least have ALL the loose material being knocked away and made safe in the meantime. You may have a mini skip load to cart off, or save as hardcore for any mini garden projects or something. The cracks are probably forming in between the loose parts and the firmly affixed areas. The fact that the crack by the step there has worked it's way up from that corner tells me that quite large piece is probably all loose, or soon will be over the next year or so.

Sorry to rabbit on.
 
Hmmm thanks, I'll look into getting structural advice, this vid might give you a bit more of an idea of the patio area

 
If it was me I'd knock some of the render off and have a look behind. See if there is any damp present and see if the render is on a mesh or straight onto the brickwork. If its on a mesh then I'd widen the cracks and then fill it with sand and cement and re-paint.
 
I've got this horrible feeling that the drainage is basically inadequate. Hate even saying that, the building has been there a long time and will remain there no doubt for a long time though and has weathered many a storm already. Does the yard ever flood, or does the drainage always cope in a squall or heavy prolonged downpour?

A mitigating factor could be that the drainage has become somewhat clogged and could use a clearing likely along it's horizontal sections. I guess the visible drain is a 6" pipe leading to a larger pipe which then leads to the sewer as you described. This sewer probably handles drainage from the road on your side also. If these places aren't cleaned periodically (say once a year at least) the same symptoms will manifest, ie the backing up of volumes of water which then ingress back up into the rendering up the wall.

One other thing I noticed on the upward look was the cement rendering above, then a base level layer then the lower rendered areas on your walls. It just makes me wonder a little bit if the cement render above is acting like a sponge and not throwing water off like it should be, ie: if it's not been treated. It could be quite pourus, which complicates things for you below a bit because if water is already draining down behind the upper concrete render layer, it'll feed straight into the top of your rendered areas. Just a consideration and one which the surveyor should be able to determine.

If that's the scenario then you could completely re-render your wall and it'll again quickly be wrecked by runoff from behind the above layer. This is hard to quantize without being close to the building and looking first hand. I take it there are one or two flats directly above yours as well which will spread the responsibilities somewhat and could lead to complications of costing/payment. Make no mistake though, there is a drainage/damp issue still present. I am very certain of this.

So if I could keep my message to you simple for the time being, I'll stick firmly with the recommendation to get a surveyor in soon. From that point you will know much better and be informed of where you stand, and more or less what you can expect to have to do to address the drainage. If the drainage is ok and just clogged then it could be prudent to have the drains cleared alone before you go as far as a surveyor. Then set about re-rendering/filling and keep an eye over the next year on what happens, then possibly go from there if you need to.

As Mark above said, keep to a cement based render, then paint, seems perfectly logical :)
 
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