# Sorting an uneven concrete floor



## LarryS.

So my garage floor has rises and dips all over it of up to 25mm at its extremes in various places, and i want to lay a wooden floor down. I've looked through the forum and as a result I'm thinking the best plan is ....
1. Put a DPC down
2. put battens down
3. level the battens
4. insulate between the battens
5. Put 18mm ply on top
6. Paint the ply

Have I got that right ?

thanks


Paul


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## MikeG.

That's one way. Another would be to level the floor with some self leveling compound, or one of the specialist 2 part products specifically for that purpose, then do a floating floor in the normal way.


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## LarryS.

MikeG.":19xy08ou said:


> That's one way. Another would be to level the floor with some self leveling compound, or one of the specialist 2 part products specifically for that purpose, then do a floating floor in the normal way.



Thanks Mike that’s reassuring, and I’ll do some maths to work out how much compound I’d need, got a feeling it would be a lot !


Paul


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## LarryS.

So I’ve just used my laser level and found the drop from back to front for the garage is 80mm ! From what I’ve read that’s too much for compound so am I back to the floating floor, with a LOT of shims ?











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## rafezetter

levelling out 80mm I think you'd be safer just using wedges to level it out temporarily - 2 x 40mm at the thick end, then use full length vertical supports at each intersection - attached to the sides of the beams, not balanced underneath, once levelled. Basically build it as you might a deck, if you are thinking down the road of a full on workbench etc, that will be heavy, plus machines etc, you'll need to consider all of that and I don't think "battens" will be enough.

2 x 2 might be enough if you make sure the beams are about 15 inches on centre in both directions, and put a vertical support at each intersection, with a DPC pad under it.

It sounds like a lot, but if you'll be moving stuff about on wheels and possible bench etc, you'll want the floor as sturdy as you can make it.

If it were I, I would make the base in 3 sections length ways then level up after, trying to do it all at once might prove tricky singlehanded.


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## LarryS.

Thanks rafe, sounds like a bit of a mammoth construction but definitely doable, I’m also going to have a look at how thin a slab I could lay too as an alternative 


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## stuartpaul

Paul,

Are you looking for a flat floor or a level floor?

Understand why you'd want a flat floor not so much a level floor. Flat is obviously much easier to achieve and with careful use of self levelling or just battens on existing should be achievable.

If you do want level than you're gonna have to do lots of wedges and levelling to get there.


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## LarryS.

stuartpaul":2zcaauu2 said:


> Paul,
> 
> Are you looking for a flat floor or a level floor?
> 
> Understand why you'd want a flat floor not so much a level floor. Flat is obviously much easier to achieve and with careful use of self levelling or just battens on existing should be achievable.
> 
> If you do want level than you're gonna have to do lots of wedges and levelling to get there.



That is a very good point I hadn’t even considered, I suppose level is probably a luxury I could do without whereas flat is critical 


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## Tervueren

If you've got sufficient height maybe using firrings front to back and lay timber or chipboard over them would do the job. Only other thing I'd mention is being a garage is the slope deliberate to avoid water ingress ?


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## LarryS.

That’s another good point about the water ingress , though without a car ever entering it again that’s probably a non issue now 

I’m now minded to try and fill in the dips / cracks for a temporary measure , then later put a dpm down, insulation on top, then 18mm plywood floating floor. Insulation as a bit of future proofing as the rest of the garage is single skin and pitched roof with zero insulation 

Would self levelling work for dips and cracks ? I’m guessing not as they’re all on a slope, so what substance do I use to fill them ??

Thanks all for the advice so far is sending me on a far different path to what I’d originally intended, that’s the power /value of the forum for you !


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## Bradshaw Joinery

A good way to achieve level is with a line laser. If you wanted to screed yourself, or use self levelling, drilling rawl plugs into the floor and setting screws in them every 1' square or so using the laser level to guage their height is a nifty way of getting it pretty damm level. (using a short batten as a guage off the top of the screw to the laser line.) this isnt much use if you need DPM. 

if you wanted timber floor, maybe get some lengths of 2x4 CLS and start at the highest point with a 30mm thickness and scribe them into the floor at 400 centres. mark where they sat on the walls, lift them, lay dpm, then put them back down insulate with 25mm and 1" ply on top. (could screw some lath between them to hold in place before ply-ing (is use a laser again here, set the timber off the deck to the line mark the scribe and cut.. 

Alternatively, Lob some DPM down and get a screed laid over the top. unless its heated a lot, isulating under screed is pretty pointless.


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## TomGW

Your garage looks like it's roughly 3.0/3.3m wide and if the slope is a gradual gradient from back to front, while being level, side to side, could you not lay a series of diminishing joists/battens from 130mm down to 50mm across the garage to achieve a level surface? If you start with 130mm at the front and 50mm at the back, with lines between, it should be fairly easy to determine what each subsequent batten needs to be and rip them on a table saw.


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## LarryS.

Hi Tom,

I'm thinking of that as a longer term plan but for now the suggestion of going for a flat floor rather than level is very appealing (as it should be a lot quicker / cheaper to achieve).

Plan is to get some self levelling compound, and have a go over the weekend. My only concern is the self levelling may not be the right stuff for small cracks / dips - so does anyone know of a better substance for the job (or a specific type of self levelling compound) ?

thanks

paul


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## stuartpaul

Paul,

I've only ever used 'bog standard' (i.e. cheap!) compound but I have played with the consistency to try and stop if flowing too far.

There are some designed for deeper (up to 50 mm) use but I've no idea what that's like.

I think if you use smaller quantities and trowel and/or straight edge it carefully you should be able to achieve a flat floor reasonably easily. Might also be worth filling in stages rather than in one go to give you more of a chance to get it to stay where you want it.

Good luck!


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## Phill joiner

I'd give a liquid screed guy a ring in your area. Just fix a 80mm batten along the door end and pump it in. Job done.


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## LarryS.

Thanks Phil, I’m going to give the compound a go first, if that’s rubbish then it may be the screed option!


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## AJB Temple

If you need 80mm why not just float a concrete screed down?


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## LarryS.

AJB Temple":3nw25h0p said:


> If you need 80mm why not just float a concrete screed down?



I’ve had a builder in to quote for a new screed floor and it’s an option I’m considering (circa 400 quid). However I’m not sure if I’d prefer a wooden floor to level and be softer at the same time rathe than pouring more concrete 

Either way I’ll be waiting til summer to make my mind up as either solution means emptying the garage of its contents for at least a couple of days 


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## LarryS.

Just been out the garage to do some odd jobs and I’ve noticed some of the plywood has lift some sort of spores all over it, is this caused by damp ?
I’d be surprised because the garage has a couple of air bricks so I’d assume that’s enough to stop stagnant air ?









Also spotted some of what looks like damp underneath the side door - the ground outside is at threshold level but the floor inside about 4 inches lower, why would the door area be damp and nowhere else? Could it be a leak through the door that’s most likely ? (The door seems really sound to me)

All of these questions are because I’ve decided to put down a floating floor so I’m wondering the best method ( considering the issues above)











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## LarryS.

Anyone ?


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## screwpainting

That is all down to damp Paul, it is coming up through the floor, and through the walls by the look of it and there is no timber based solution for it. 
Avoid floating floors like the plague, it's the most idiotic flooring system ever conceived of and is only as good as the care taken to lay it onto whatever subfloor surface it is covering. It will not work on top of a very uneven concrete finish without that surface being spotlessly clean and properly prepared and that is more work than screeding the bloody thing properly in the first place. 
As an insulation technique, it is fine if there is no other alternative, but I personally, think, it's still a handy bodge for all involved who offer no personal guarantee to the poor sod that has to have it all ripped out four or five years later along with whatever has been installed on top of it because it has sunk, makes a noise, rocks and rolls, or gone rotten in some way. 
Again, great if done perfectly, but... just don't trust anyone to do it mate.

If I had your problem, I would first check the thickness of the existing concrete and look for evidence of a membrane and then establish precisely what you 'definitely' have in the way of a DPC as opposed to guessing.

I bet that floor is made up of all sorts of crapery and would be dead easy to turn into hardcore for a proper job of concreting a new floor right up to spec, damp free, flat and as smooth as a babies.
Sorting out a lack of a DPC is cheap and easy if necessary, just a little care and application and simply has to be done anyway. 
The cost is all in labour, care and some newly acquired, simple skills. 

Just my two pennyworth :wink:


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## SammyQ

That is massive damp Paul. I agree with Screwpainting that you have to address the penetration problem before anything else. You mention outside ground level is 'high'? Remember, the damp course has to be 6"/150mm *above ground level*? I would start by digging away the soil banked against the walls to restore this. Second, do you have a *visible* DPC in your walls? Is it in good nick? If so, fine, proceed. If not, see later. 
Is your floor emitting damp? Easy way to tell: tape a freezer bag to the floor, well sealed edges, leave for a day, if condensation _underneath_ you have upwardly penetrating damp. If on top surface only, you've got a ventilation problem, floor's fine.
Faulty wall and floor damp problems CAN be sorted. injecting and tanking come to mind. But, and it's an ocean-going-liner-size of a 'but', you have to make the place dry before you can do owt else. Mould spores LOVE 'free' water to germinate.
From experience, I can also tell you that those manky chipboard pieces will have to be replaced. As a Biologist with 40 years experience, I have never found a totally foolproof way of removing and then preventing resurgence of mould in 'reconstituted wood' - probably as it has such a massive pore structure and the spores of mould seem to hide in them? 
There is an outside possibility that this is the worst condensation problem I have ever seen...but I don't think so; there seems to be just SO much fluid there, you'd have to be sleeping in the garage or cooking in it to provide the amount of moisture visible in the photos. The only other thing I could think of would be an unvented tumble dryer and I can't see one in the pikkies.
Finally, drying this baby out will need the winds and temperature of spring and summer. I would halt any thought of flooring until the problems are sorted. DAMHIKT. Sorry to be such a Jeremiah, but cash in a three-kid family is precious, I know, because I had 'three under three' at one point, who went on to be three at Uni simultaneously...  

Sam, older, wiser, but still optimistic.

Edit P.S. Had anudder look at that floor. It's a piece of p1$$. Personally, I would break it up and relay it with a 1000 guage membrane underneath and 8"/200mm up the walls, or, if cash/time is tight, I would lay down a good, meaty, pair of coats of summat like Synthaprufe* - anything thick, tarry and plastic-setting (pliable) would work. I've even seen a quick skim of dry concrete troweled on to smooth out rough and sharp edges, then several days later, a coating of roofing cement, quickly followed by a rolled-on DPM. Rough as a bear's ariss, but it worked. The rube that did this, laid his floor and insulation on top and it worked. Just say'in... more ways to kill a cat than chokin' it with cream....

*https://www.wickes.co.uk/Ikopro-Synthaprufe-Trade-Damp-Proofing-Liquid---5L/p/151384


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## Woody2Shoes

I think that quite a bit of the mould on vertical surfaces is from condensation - is warm (relatively moist, from a kitchen/utility/bathroom) air able to infiltrate from the house to the garage? A tumble-dryer (even a condensing one) in the wrong place would explain everything.

Part of the solution to the problem may simply be to create a vapour-tight 'airlock' between house and garage.

Also, airbricks are all well and good but do they give proper cross-ventilation, without 'dead spots'?

I think that you do need to investigate the cause of the dampness on the floor under the side door (it's not impossible that this is simply accumulated condensation running down the smooth-glossed inner face of the door) Cheers, W2S


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## SammyQ

I second what W2S ses. If there IS a humidity source venting into your garage space, Bingo!
Sam.


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## LarryS.

Thanks everyone for the input, it sounds like I've got a bigger job on my hands than I thought, but i want to do this right as it's intended to be turned into a proper workshop over the next few years.

I'll go out on the weekend and check DPC, but to answer some questions / points.

Water ingress - The garage at some point has had the original big doors replaced with a roller shutter, which is mounted on the inside of the opening. Problem is the ground outside was angled for the original doors, where the new doors are there's a slight slope INTO the garage, which means on a rainy day there will be a puddle about 2ft x 2ft and a slim covering of the floor - so is that enough to cause the damp issue ?

Outside ground - its not actually soil that's hugher than the inside floor, it's a concrete path that is laid alongside the garage that is about 6 inches above the floor level, no idea why they'd have done that - but is taking that out and digging down the only solution? 

thanks again for the guidance / advice !


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## SammyQ

Paul, find your damp course on the _inside_ of the garage. If your wall is one brick thick, the outside pathway HAS to be 6" below the dpc. If you have a double skin wall, in theory you could have an internal 'step' in the dpc, allowing for a higher outside path, but I greatly doubt it's a good idea. MikeG may want to correct and enlighten me, he's better at this than most here. Banked up material of any sort, bridging a dpc, equals damp rising up the walls and humidity diffusing from them causing havoc. 
Secondly, that puddle is a complete non starter. THAT is - I earnestly suspect - is a major contributor to the humidity in your garage that the mouldies LOVE and flourish in. Great encourager of the tin worm too. It's got to go. Improved drainage or reversing the slope outside,( with a cast sill, upon which the door rests?) even a simple soakaway would magically help.
Keep asking fella; weve all been there and can guide your thinking. Save heartache and frustration by avoiding our ballsups. Experience "is a hard mistress in that she gives the lesson AFTER the sanction". Us old lags would rather that fewer noobies got pummelled by her. 
Sam, been there, cocked up that.


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## LarryS.

Thanks Sammy, the inside is rendered so I guess I’ll need to hunt for a doc black line outside ?

The only damp I’ve noticed is the puddle plus that small amount around the door area, so maybe a puddle fix and door may solve most of the problem. I’m also going to do a hunt to see if there is more mould around the garage but have seen nothing obvious til now, so maybe there is a dead spot on the airflow

Casting a new cill sounds very doable; ideally I want to build garage doors back in their original position but having time for that is probably a few years away !


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## MikeG.

LarryS":2l3y2283 said:


> .........Outside ground - its not actually soil that's hugher than the inside floor, it's a concrete path that is laid alongside the garage that is about 6 inches above the floor level, no idea why they'd have done that - but is taking that out and digging down the only solution? .......



It's not the only solution, but it's part of the only proper solution. This is the very first thing I get clients to do with any of their old buildings: lower the ground level around the perimeter until it is 6 inches lower than the finished floor level. Sometimes this isn't practical, but even getting it 2 inches below the floor level will be a huge improvement. It also shouldn't be a solid surface adjacent to the building, with shingle being the best thing to have against the wall. Lowering the ground level at the sides will force you to lower the ground level at the front, too, which will help reduce the water ingress at the door, (an absolute disaster at the moment). This advice all applies whether or not there is a DPC, (and not having a DPC isn't the huge deal that some will claim). I'd be looking at an Acco-type channel-with-grill drain in front of those doors, in addition to sorting out the levels, but such a drain only works if there is a suitable place to discharge to.

Of course, you can achieve the same ground level to floor level difference by raising the floor level, if this works with floor levels in adjacent rooms, head heights, adjacent DPCs, and so on. I am really reluctant to try to give you a personalised solution in your specific case because walking around the building is the only way really of finding out what is actually happening. 

As a first course of emergency action, stand a dehumidifier in there, and empty it regularly. This is no long term solution, though, as you are essentially trying to dehumidify Dorchester......a losing battle. I can't stress enough that mould is dangerous. It has serious health implications, and once you get everything dry, you should be cleaning everything down with an anti-fungal solution, and disposing of any affected timber (such as that plywood).


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## Woody2Shoes

LarryS":1y8lgbak said:


> Thanks everyone for the input, it sounds like I've got a bigger job on my hands than I thought, but i want to do this right as it's intended to be turned into a proper workshop over the next few years.
> 
> I'll go out on the weekend and check DPC, but to answer some questions / points.
> 
> Water ingress - The garage at some point has had the original big doors replaced with a roller shutter, which is mounted on the inside of the opening. Problem is the ground outside was angled for the original doors, where the new doors are there's a slight slope INTO the garage, which means on a rainy day there will be a puddle about 2ft x 2ft and a slim covering of the floor - so is that enough to cause the damp issue ?
> 
> Outside ground - its not actually soil that's hugher than the inside floor, it's a concrete path that is laid alongside the garage that is about 6 inches above the floor level, no idea why they'd have done that - but is taking that out and digging down the only solution?
> 
> thanks again for the guidance / advice !



Yikes!! - puddles are a definite problem, so are outside ground levels - as Mike says.

Is there an opening into the house from the garage? Are there any machines like tumble dryers?

Cheers, W2S


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## SammyQ

That's the definitive answer Paul. MikeG is THE source on this forum for building issues. I fully concurr with him re medical issues from mould spores; I had not wanted to increase your groan factor by raising it, but hinted above that the wood needed replaced? Basically, think asthma, bronchitis, Farmers Lung as a starting point! 
Good luck, and please come back as often as you feel the need. PM's are also welcome if you feel you don't need to ' broadcast'to the whole forum. Just don't ask for lottery numbers... 8) 
Sam


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## LarryS.

Apologies this is photo heavy, but a bit of an attempt to show the layout / surrounding area, so I've taken some photos. 

The setting of the garage, basically at the top of the slope of our driveway:







At the door you can see the roller shutter, that comes down BEHIND the opening, where the original doors would have been, and the slope away starts, so the movement of the shutter to the inside causes rain water to seep under. You can see the dark conctrete where the water goes under, behind the door






The DPC it turns out is only one brick above ground level right at the front






And at the left hand side the path starts 1 brick below DPC 

but by halfway up the garage is only 1 inch below it






by the time we get to the back, the DPC is crossed, and the ground is higher again, plus there is a wacking great big oil tank there with its pipe concreted in






Down the other side of the garage looking from the front again the DPC is crossed again, with the ground, and unfortunately next door are growing a eucalyptus (or something like that) which I am constantly battling to keep down - but it is riddled down that side







So in short dropping thr ground all the way around looks like a fairly huge task....is there an alternative ? I understand a bit about "tanking" could that be an option, plus raising the DPC up and tanking to that point ?


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## MikeG.

OK, well there is some good news in all that. With the garage sitting on the top of a sloped driveway, sorting out the issue at the roller shutter door threshold should be fairly straightforward, and in particular, there is an RWP (downpipe) adjacent.

I would start by digging away at the front of the garage to reduce the ground level of the drive at the threshold, but still have that drive sloping away from the building (ideally by about 1 in 40). I would also dig a shallow trench in front of the garage door, and install in it a gulley with grill,like this. Check that whatever you buy is suitable for whatever traffic it is likely to have to cope with. Some of these channels come with a built-in slope, and others you have to lay to a slight fall. Whatever system you install should shed its water towards the downpipe on the right hand side of the door as you stand on the drive looking at the garage. You'll obviously need to dig away around the downpipe to expose the drain and make a connection to your new gulley. This should entirely resolve the issue of water ingress at the garage door threshold.

I presume that the door adjacent to the oil tank is the door showing the damp issues in your earlier photos. Firstly, I'd be closely examining the nearby downpipe to see if that is leaking. If the junction with the gutter isn't perfect, water will often run down the outside of the pipe, and can be pretty difficult to spot. That little return in the wall by the tank (or is it the end of the garage?) doesn't help either, because that is an obvious moisture trap. Can you check to see that the paving there falls away from the building, such that rain has a chance to run away down the path........or does rain get trapped against that wall in the corner?

Personally, I'd prioritise the front door and the gutters/ downpipes etc, and do the plastic-on-the-floor trick to see if groundwater is getting through your concrete in the middle of the garage..........and that's pretty much all I'd do this winter other than clearing any detritus from the narrow area alongside the boundary fence. I'd install a dehumidifier as I suggested earlier, and just monitor damp levels in there into the spring and early summer. I absolutely would not do any tanking internally until things were much drier than now, and we'd need the results of the plastic-on-the-floor test before assessing whether digging the floor out and installing a new one is worthwhile. It probably is, but this will also involve raising the side door threshold and thus getting a new door, so let's not rush at that.

I can see value in breaking out the concrete footpath and laying a new path at lower level. That would probably entail a step, or a short ramp, at the corner by the oil tank, so you'd need to assess the practicalities of that. The new path should be away from the garage wall, six inches if practical, and the gap filled by shingle.


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## beech1948

MikeG is right in his approach to what you should aim for this winter.

I would add that the narrow RHS strip between you and the neighbour has what looks like an invasive bamboo ( not eucalyptus). This will also add to your problems as bamboo is able over time to breakthrough 3-4 inches of concrete. An approach here is to dig it out (ouch) and to put down a layer of herbicide and salt or something which will persist and maybe spread to kill the offending bamboo next door. Maybe talk to the neighbour about it as digging it up is hard work. 

A busy winter ahead it looks like


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## screwpainting

Looking at those pictures Paul, I think it looks as if all the surrounding ground and particularly the actual path on the left hand side, actually fall towards the garage. This could easily inundate and overwhelm that dpc in heavy rain and I think it might be a good idea to check this with say a dustbin full of water tipped over by that oil tank (proper scientific)and just see where it actually goes. 

What you could do is make a hole in the roof, then you would have the full set of possible water ingress points, looks like you have all the others there mate  . 

MikeG has pretty well summed it up.


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## MikeG.

I'd just nuance what screwpainting has said by saying that the DPC is only important for protecting the brickwork above the DPC, but not for preventing water getting into the garage below it. This is why I said earlier not to be too fixated on the DPC, because even a properly placed DPC, 2 courses up from where it is now, would make not a jot of difference to how much water is getting into your garage.

I get to deal with ancient buildings a lot, and with older-but-not-ancient ones too, and they invariably have no DPC at all. Damp can be well managed in those by paying close attention to the fundamentals, as we're doing here with this garage, and the DPC or lack of is an irrelevance. This doesn't take away from what screwpainting has said about getting the falls away from the garage walls.........another good argument for removing that side path (if it is falling towards the garage).


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## SammyQ

Yup. Dat am bamboo Massa Paul. Flamethrower and JCB Suh....odderwise you'se'a gonna be overwhelmed. 
Sam(bo) ...with deep apologies to Samuel Langhorne Clemens...
Edit: Wrong! Not Clemens, Gerald Durrell.


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## LarryS.

Thanks Mike / Sam, I’ve put down the plastic plus a paint tin so I’ll see in the morning if the floor is shot 





As for the works needed I may have the time to do the garage front but the rest of it is probably months away (3 small kids) so I may have to put up with the damp for a while yet. Good point on the down pipe though I’ll check that tomorrow as it’s been blocked before.




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## MikeG.

LarryS":1yi5ztll said:


> ........ I’ll see in the morning if the floor is shot........



Leave it 24 hours.


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## SammyQ

Yup. More if you can; over this weekend maybe? Dunno if there has been much precipitation where you are, but it's been dryer and frozen here, which tends to limit water ingress, so clagging up the polythene could be slow. 
Sam


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## LarryS.

Rained most of yesterday and this is the result, so very slight darkening

I’m guessing that means bad news ? 






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## MikeG.

Actually, no, I'm seeing that as good news. It confirms that you have to deal with that floor properly. It has to come out (it doesn't look like it will put up a lot of resistance), and a new one poured over a DPM. Hire or borrow a Kango, start at an edge and nibble off small chunks, and that floor will take half a day I reckon. You really don't have to do this until summer, when you'll be able to empty the workshop and store stuff safely under tarps etc if necessary.

I'm always glad when the answer is obvious, because then you know that what you are proposing to do will actually fix the problem. Nothing worse than "let's give this a go" and then finding that it makes no difference. Here, it isn't the only issue to be dealt with, but if you fixed everything else and left this floor, you would still have a damp workshop.


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## SammyQ

Hi Paul. At the risk of being seen as sycophantic, I totally agree with MikeG; floor has to come out, both as a fix for it's own problem AND as a basis for a little more work on the walls. 
I also agree that the floor looks shot and a half-decent Kango will chew it up pronto, maybe 2 hours. I found a pickaxe handy to prize it up in larger slabs (easier to move to the skip*) when I did my excavation work and my five foot crowbar ( now in its third family generation) was perfect tool too. Rugged gloves are an absolute requirement, as the riven edges of the concrete fragments are like razors. You COULD think of breaking up the old slab in situ as hardcore for the new pour, but I suspect you may have to dig down min 6" and then install a new DPM - on sand blinding - before chucking some 'muck' on and levelling to floor level. Mike, or any competent builder, please correct and/or contradict a weekend warrior's witterings in this respect. The nice thing is, once you put in two days work, the new floor will make everything better, and you remove heartache and frustration as your tools and projects suffer from damp and its camp followers, rust and mould.
Sam, with memories of doing a whole kitchen like this...
* Larger slabs mean more material per lift, less farting about with a shovel; far less 'housekeeping' to prepare for new pour. Just mind your back, get a helper.


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## LarryS.

Thank you both, sounds like my only option is fairly big works....

Dig out path on left, bamboo on right, ground at back, and then the floor of the garage, then 

re-lay floor with a DPM, put in a drain at front and a soak way for it (current downpipe just drains into a gravel siding to the drive), build a new lower path on left (we need that access). So much for hoping this would be easy but I’m happy that this is a full and proper solution.
If there are any shortcuts which would result in a viable solution then please shout!

Thanks again


Paul




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## SammyQ

Sorry Paul, but you have to get the basics right make future work viable. If it is any comfort at all, in the last three months I have had to, :
1)Install a new gas boiler 
2) install a full loft of insulation
3) Employ a drainsman with a camera and a 4000 psi lance
4) Employ a builder to stop rising damp
5) Take on a professional rodent exterminator
6) Remove a substantial amount of concrete and half a tonne of soil, causing underfloor damp.
7) Remove and then replaster behind, a built in wardrobe, as the mould in it rotted boots and coats. 

*This is not my garage, it's my (new-to-me) home!!* And, we're not done yet! The builder is coming back tomorrow to install air vents below the damp course to help dry out a sopping underfloor. 

Want to know WHY all this is going down?? Because, just like your garage builder, a builder serving two-owners-before-me was CARP at his job and left behind horrors. The elderly couple before me just threw spondulicks at the problems, didn't investigate, didn't rectify. POLTROONS!! I feel for you Paul. I have already done a similar job over a number of years, to my previous place in Belfast, while raising three kids. It ain't easy, or quick, but it is *wholly *satisfying to make things better. 

Hang in there Spud.

Sam


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## LarryS.

All understood Sam and as ever i'll get it done, recent experience though with the 3 kids and the puppy was I was asked to hang a picture up, it took 3 days to find the time !




Paul


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## SammyQ

=D> =D> =D> 

Sam


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## autotrans

(hammer) (homer)


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## LarryS.

Ok so as predicted with 3 children it’s taken time to get going but as of now we have an extension being built on the house , and whilst we’re at it I’m getting the garage sorted

Pictures attached but so far
1. Path on the left has been dug down to 2 courses below dpc
2. Garage is mostly emptied (will finish tonight)
3. I’ve got a breaker ready to take the floor up
4. A new floor and dpm will be installed Friday 

Supplementary question I’m hoping someone can help with. The floor to rafters height is only 230cms, rafters to underside of the ridge beam is 1m, so I’d like to take each rafters out one at a time, shorten it, and raise it 30cms before reattaching with m10 bolts. Does that sound like the right way to do it ? I’ve done a lot of internet research but most answers come back with an American accent, and I’m not sure they have the same approach as if need here 




















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## LarryS.

Oh, and I’ve got a 10mm armoured cable run up underground and into the garage, very excited for that upgrade compared to the 2.5mm cable that was previously swinging from a catenary wire 


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## beech1948

LarryS,

I was catching up on your progress by accident and thinking about the RHS of the garage where the bamboo or whatever is coming through. A simple and cheap solution is to put down a layer of salt ie. typical domestic salt. Cover the whole part between the boundary and garage and lay it on thickly. The bamboo/eucalyptus will start to die very quickly.

Al


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## LarryS.

Al

If that works then that is a great idea, I’ve been putting off that part of the work til last 

More progress today, floor dug out is high as predicted was full of rubble, I’m beat

Can anyone give me feedback on raising the rafters as I’ll be doing it in the next few days hopefully 
Cheers










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## Sheptonphil

LarryS":2ui5tgqt said:


> Can anyone give me feedback on raising the rafters as I’ll be doing it in the next few days hopefully
> Cheers
> Sent from my iPhone using Tapatalk Pro


Excellent work digging out that lot. 

Why are you raising the rafters? Looks like you have loads of headroom already. Just curious.


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## beech1948

Re your rafters.

I think the rafters are the ones which rise from the sole plate to the ridge. What you call a rafter is properly called a tie beam. Its job is to prevent the rafters spreading and causing the walls to bow outwards from the weight of tiles on the roof.

If you want to remove one and then shorten it and raise it up say 300 mm or so then you are OK to proceed. Removing one will not cause any issues with your roof. Replacing it say 20 mins later but 300 mm or so higher will not cause any problems. You should consider maybe fastening the rafter to the brick with a 18" length of what I know as "builders band" a galvanised steel band say 1" to 2" wide which can be twisted into the shape you need and screwed into wood or brick using trad fixings. Problems can occur if you try to go too high with the tie beam but you mentioned that you were looking for a smallish increment in height available.

Al


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## LarryS.

Sheptonphil":64c7uaep said:


> LarryS":64c7uaep said:
> 
> 
> 
> Can anyone give me feedback on raising the rafters as I’ll be doing it in the next few days hopefully
> Cheers
> Sent from my iPhone using Tapatalk Pro
> 
> 
> 
> Excellent work digging out that lot.
> 
> Why are you raising the rafters? Looks like you have loads of headroom already. Just curious.
Click to expand...


As Al has pointed out i got the terminology wrong, its the tie beams I want to raise, and it's because their height at the moment is 230cms but i want to be able to handle 240cm sheets, so a 20/30 cms rise should sort it


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## LarryS.

beech1948":32muvqtr said:


> Re your rafters.
> 
> I think the rafters are the ones which rise from the sole plate to the ridge. What you call a rafter is properly called a tie beam. Its job is to prevent the rafters spreading and causing the walls to bow outwards from the weight of tiles on the roof.
> 
> If you want to remove one and then shorten it and raise it up say 300 mm or so then you are OK to proceed. Removing one will not cause any issues with your roof. Replacing it say 20 mins later but 300 mm or so higher will not cause any problems. You should consider maybe fastening the rafter to the brick with a 18" length of what I know as "builders band" a galvanised steel band say 1" to 2" wide which can be twisted into the shape you need and screwed into wood or brick using trad fixings. Problems can occur if you try to go too high with the tie beam but you mentioned that you were looking for a smallish increment in height available.
> 
> Al



thanks Al you were right on my incorrect terminology. What is the purpose of the builders band strapping for the rafters?

And Phil - the dig out was tortuous, especially on such a muggy day, but it's done now and i'm guaranteed to sleep deeply tonight 

paul


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## beech1948

LarryS,

When/if you raise the tie beams by say 300mm then I expect the rafters to be secured to the sole plate by a birds mouth cut out in the rafter end to fit to the sole plate. This would/should have at least 2 or more nails through the rafter end into the sole plate. I was just thinking that its not a lot to hold the weight of the roof over any single rafter and a bit of extra security might be handy. It would hold the rafter down onto the sole plate because it would be secured into the wall below thus pulling the roof down onto the load bearing surface. 

I'm always over building and believe belt and braces is probably the best policy. Perhaps overly cautious.


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## beech1948

Lets see last post was August....any updates. ?


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