Why does my garage fill with water when it rains?!
Discussion
Right, garage is a single skin building built on a concrete base. Guess it was built the same time as the house (about 25 years ago). Flat roofed, but this doesn't appear to be leaking.
When it rains heavily, the floor of the garage always turns into a large puddle.
Previous owners have built a patio up against the side of the garage and piled earth up round behind it. I assumed that they'd placed this above any damp proof protection and water must be coming through the walls. So I've been digging (quite a deep hole) to try and expose some kind of damp proof layer. This is where my knowledge of building stuff breaks down... Am I right in guessing that the base was laid on a damp proof sheet? It looks that way, and the edges of the sheet were tucked round against the bricks (on the outside) and earth piled up against it. Anyway, there is definitely some kind of sheet against the lower outside bricks and its knackered. Its split all over the place and just crumbles away if you touch it. The bricks behind it are soaked and I'm pretty sure water must be coming through whenever it rains.
What can I do to stop the water getting in? I'm guessing I'll have a lot more digging to do...
When it rains heavily, the floor of the garage always turns into a large puddle.
Previous owners have built a patio up against the side of the garage and piled earth up round behind it. I assumed that they'd placed this above any damp proof protection and water must be coming through the walls. So I've been digging (quite a deep hole) to try and expose some kind of damp proof layer. This is where my knowledge of building stuff breaks down... Am I right in guessing that the base was laid on a damp proof sheet? It looks that way, and the edges of the sheet were tucked round against the bricks (on the outside) and earth piled up against it. Anyway, there is definitely some kind of sheet against the lower outside bricks and its knackered. Its split all over the place and just crumbles away if you touch it. The bricks behind it are soaked and I'm pretty sure water must be coming through whenever it rains.
What can I do to stop the water getting in? I'm guessing I'll have a lot more digging to do...
I'm sure that proper damp proof material shouldn't have disentegrated like that, maybe they used the wrong stuff. From the sound of it you effectively don't have a damp proof layer any more, I would have thought this would lead to water seapage rather than sudden flooding though? So this doesn't necessarily account for the flooding.
As far as the damp proof layer goes, perhaps there's something you can paint onto the outside of the brickwork to seal it? Would probably require digging down to the foundations.
On the other hand if the leak isn't *that* bad perhaps it would be easier to stick half a dozen pallets down to keep your feet dry?
As far as the damp proof layer goes, perhaps there's something you can paint onto the outside of the brickwork to seal it? Would probably require digging down to the foundations.
On the other hand if the leak isn't *that* bad perhaps it would be easier to stick half a dozen pallets down to keep your feet dry?
I'm of the opinion that attempting to seal in any moisture is not necessarily the best way to do things.
You can seal it out of your garage, but that water still needs to drain somewhere or other. I suggest if you definitely trace the water coming down the side of their patio, that you dig a trench, install a drainpipe for the water to flow into, and connect that drain to the nearest drain pipe.
Pictures would be a massive help.
You can seal it out of your garage, but that water still needs to drain somewhere or other. I suggest if you definitely trace the water coming down the side of their patio, that you dig a trench, install a drainpipe for the water to flow into, and connect that drain to the nearest drain pipe.
Pictures would be a massive help.
Ok here are some pics, bit low res but I've not got much free webspace.
These are the side wall, with the patio alongside it.
http://web.ukonline.co.uk/david.merriman/inside.jpg
http://web.ukonline.co.uk/david.merriman/outside.jpg
This is the corner at the back where I've dug (a now rather pathetic looking) hole to see if I could tell what was going on.
http://web.ukonline.co.uk/david.merriman/outsidecorner.jpg
http://web.ukonline.co.uk/david.merriman/insidecorner.jpg
Oh and a bit of what I think was once the damproof
layer
http://web.ukonline.co.uk/david.merriman/dampproof.jpg
Thanks for the help folks, I want to build a kitcar in the garage so a certain degree of waterproofing would be good
EDIT - garage has pretty much dried out now, water always lies along that wall last as its the lowest point, so its not so obviously coming in that way
EDIT2 - yikes don't edit posts with links in
>> Edited by d-man on Saturday 16th April 17:38
>> Edited by d-man on Saturday 16th April 17:43
These are the side wall, with the patio alongside it.
http://web.ukonline.co.uk/david.merriman/inside.jpg
http://web.ukonline.co.uk/david.merriman/outside.jpg
This is the corner at the back where I've dug (a now rather pathetic looking) hole to see if I could tell what was going on.
http://web.ukonline.co.uk/david.merriman/outsidecorner.jpg
http://web.ukonline.co.uk/david.merriman/insidecorner.jpg
Oh and a bit of what I think was once the damproof
layer
http://web.ukonline.co.uk/david.merriman/dampproof.jpg
Thanks for the help folks, I want to build a kitcar in the garage so a certain degree of waterproofing would be good
EDIT - garage has pretty much dried out now, water always lies along that wall last as its the lowest point, so its not so obviously coming in that way
EDIT2 - yikes don't edit posts with links in
>> Edited by d-man on Saturday 16th April 17:38
>> Edited by d-man on Saturday 16th April 17:43
It certainly looks as though the Patio is causing water to drain into the garage.
I'd permanently remove one row of flags, and fill the area (down to a good solid depth) with material that allows the water to drain naturally. Don't put any soil or plants there, as they will just make the problem worse. A drain would still work wonders.
Another option of course is to remove all the flags, and dig down to the same level as the garage floor - lots more work, but it would allow you to flag up to the garage wall?
I'd permanently remove one row of flags, and fill the area (down to a good solid depth) with material that allows the water to drain naturally. Don't put any soil or plants there, as they will just make the problem worse. A drain would still work wonders.
Another option of course is to remove all the flags, and dig down to the same level as the garage floor - lots more work, but it would allow you to flag up to the garage wall?
Yeah thats pretty much what I thought. I'll probably just remove that row of paving stones and put something down there to drain the water away.
The patio itself isn't too bad, its only about 1 layer of bricks over the garage floor level. Round the back of the garage is another story though, it's at least 3 bricks deep there and full of all sorts of rubble too.
Looks like I've got some digging to do...
Still interested in how these are actually built. Does the concrete base just sit on a damp proof layer? And what should happen to the 'excess' of the layer that overlaps the base. There is definitely some kind of rubberised material against the lower layer of bricks round the back of the garage, not sure if it goes all the way underneath the floor or not as I've not managed to dig that far yet. It looks like it was put there to protect the lower bricks at the back of the garage, but its all rotting away.
Thanks again
The patio itself isn't too bad, its only about 1 layer of bricks over the garage floor level. Round the back of the garage is another story though, it's at least 3 bricks deep there and full of all sorts of rubble too.
Looks like I've got some digging to do...
Still interested in how these are actually built. Does the concrete base just sit on a damp proof layer? And what should happen to the 'excess' of the layer that overlaps the base. There is definitely some kind of rubberised material against the lower layer of bricks round the back of the garage, not sure if it goes all the way underneath the floor or not as I've not managed to dig that far yet. It looks like it was put there to protect the lower bricks at the back of the garage, but its all rotting away.
Thanks again
It looks like your damp proof is where the arrow is pointing
and is below ground level. You should dig out around the garage to below this level. If the damp proof is broken you could use a chemical barrier by drilling into the wall and injecting it or get someone to do it for you
>> Edited by falcemob on Saturday 16th April 19:52
and is below ground level. You should dig out around the garage to below this level. If the damp proof is broken you could use a chemical barrier by drilling into the wall and injecting it or get someone to do it for you
>> Edited by falcemob on Saturday 16th April 19:52
Ferg said:
Is the ground outside higher than the slab?
Yes and significantly so, its obvious even to me that in this situation the water is going to run out of the ground, through the wall and straight into the garage.
Hence my questions about some other possible damp proof material that I discovered that seems to have been put in vertically behind the garage, up against the bottom 2 or 3 layers of bricks... I can't yet see how deep this goes. This has now largely disintegrated. I guess this was put there to prevent the problem, but would this be part of the construction of the garage and if so is it replaceable now?
The arrow points at the first layer of bricks above the floor level of the garage, there does appear to be a damp proof course there but I think I'll have to dig deeper to get round this problem... Otherwise water will still be able to run underneath the dpc and yet still be above floor level inside.
I think this diagram roughly matches how the garage is built
www.pavingexpert.com/images/concrete/xs150gb.gif
I'm not sure about the keeled part and the bricks seem to be right on the edge of the concrete, but that is how I think its built. The ground is currently above the pink dpc on that diagram and significantly above the floor level of the garage.
Cheers again for all your help... PH seems to be the font of all knowledge for just about anything
>> Edited by d-man on Saturday 16th April 20:47
You have a bit of DPC in the last pic, what row of bricks did you get it from?
The picture on the inside looks like it could have the DPC on the top of the first line of bricks but it is hard to tell properly. Is the concrete floor of the garage below the level of the ground outside?
The picture on the inside looks like it could have the DPC on the top of the first line of bricks but it is hard to tell properly. Is the concrete floor of the garage below the level of the ground outside?
Oh and that bit of damp proof stuff was part of a much larger piece that appears to be in place vertically against the bricks at the back of the garage. Its pretty much gone from where I dug the hole, but I can see more bits of it sticking out of the ground further along. Its in very bad condition and just breaks up when you touch it.
I hate to say it but I doubt you garage is built as well as the diagram you showed.
I recognise the bricks that your garage is made of. They're LBC heathers. Brikkies love them, because they're cheap, and nice and precise in shape and size, and hence quick to lay.
The last part is the indicator. Cheap and cheerful.
These particular bricks are hopeless for water absorption. My house is built from them, and so is the garden. For me it's a mixed blessing. The garden needs alot of brickwork, because it's sloping and heavily terraced, but this does mean that the ground level is well below the DPC. On the down side, I don't think there was a single brick that came out of the garden that hadn't blown through frost. They've been replaced with some similarish coloured stock bricks.
I think your problem needs sorting out sharpish, if not before, to minimise the risk of frost damage to the bricks.
My house was built in the mid '70s and quality of construction was abysmal. The only rule they observed was the first rule of building.
> Nothing but the construction should be above DPC. <
In order that you can drive your car into the garage, the floor would normally be below DPC, but above ground level. If those rules are followed you get a reasonable garage, that isn't constructed to the current standards.
If your garage is built to the current standard, you ought to be able to shelter in it, in the event of Nuclear War.
Happy digging
Edited to add;
When building garden terracing/retaining walls a DPC is not practical. The recommendation is to backfill at the base with pea shingle and pierce the wall with drainage ducts of at least two inches diameter.
The recommendation also suggests the use of Bitumastic paint on the inside face of the retaining wall. At least two good coats are required.
If you use a drainage duct and pea shingle, to pave up to the garage, I'd personally dig down to footing and apply the paint from ground level all the way down to the footing.
>> Edited by dilbert on Saturday 16th April 21:36
I recognise the bricks that your garage is made of. They're LBC heathers. Brikkies love them, because they're cheap, and nice and precise in shape and size, and hence quick to lay.
The last part is the indicator. Cheap and cheerful.
These particular bricks are hopeless for water absorption. My house is built from them, and so is the garden. For me it's a mixed blessing. The garden needs alot of brickwork, because it's sloping and heavily terraced, but this does mean that the ground level is well below the DPC. On the down side, I don't think there was a single brick that came out of the garden that hadn't blown through frost. They've been replaced with some similarish coloured stock bricks.
I think your problem needs sorting out sharpish, if not before, to minimise the risk of frost damage to the bricks.
My house was built in the mid '70s and quality of construction was abysmal. The only rule they observed was the first rule of building.
> Nothing but the construction should be above DPC. <
In order that you can drive your car into the garage, the floor would normally be below DPC, but above ground level. If those rules are followed you get a reasonable garage, that isn't constructed to the current standards.
If your garage is built to the current standard, you ought to be able to shelter in it, in the event of Nuclear War.
Happy digging
Edited to add;
When building garden terracing/retaining walls a DPC is not practical. The recommendation is to backfill at the base with pea shingle and pierce the wall with drainage ducts of at least two inches diameter.
The recommendation also suggests the use of Bitumastic paint on the inside face of the retaining wall. At least two good coats are required.
If you use a drainage duct and pea shingle, to pave up to the garage, I'd personally dig down to footing and apply the paint from ground level all the way down to the footing.
>> Edited by dilbert on Saturday 16th April 21:36
Oh I doubt its that well built too. Both my and my parents houses date from the 70s and the build quality on both is... interesting.
As I said the bricks are right on the edge of the concrete base and I doubt its keeled like the one in the diagram. It does show how the bricks are built on top of the concrete base though, which is what my eyes tell me when I look at it, but I wasn't sure that was a sensible way to build something
Anyway I'm gonna have to get digging to get the floor of the garage above ground level and see where I go from there... This could take some time.
Thanks for everyones help, I still wonder what the material I found against the outside back wall of the garage was doing there though... Is it some recognised way of combatting the problem or has someone just bodged it in the hope it goes away?
As I said the bricks are right on the edge of the concrete base and I doubt its keeled like the one in the diagram. It does show how the bricks are built on top of the concrete base though, which is what my eyes tell me when I look at it, but I wasn't sure that was a sensible way to build something
Anyway I'm gonna have to get digging to get the floor of the garage above ground level and see where I go from there... This could take some time.
Thanks for everyones help, I still wonder what the material I found against the outside back wall of the garage was doing there though... Is it some recognised way of combatting the problem or has someone just bodged it in the hope it goes away?
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