New patio is falling towards house..

Xander10

https://www.boards.ie/discussion/comment/119004673#Comment_119004673

Don't know much about patios except having one dome recently. Are you saying the slabs are just sitting on the original path?

My man, didn't dig up the existing path, instead put a block frame in and filled it with hard core and a sand base.

mickdw

The guy is a cowboy, I mean it even dips locally at the door as well resulting in the puddle forming at the door.

Now there are sites that are awkward etc and need abit of thinking but even in the case of the rear garden being higher than floor level, the sensible thing to do is slope away from house for a sensible distance to a drainage channel. You then have abit of freedom with slopes from channel outwards.

toyotatommy

Unfortunately we are in a building boom and this is the standard of work.

tonium22

That job is an insult to cowboys

I do a bit of patio/paving and refurbishing

Never seen anything that bad

Try to get him at the minimum to rip it all up otherwise nobody will touch it to fix it

Stack the cut slabs neatly so they will be handy to relay

He'll block your number now and you'll never see him again

Where in the country are you located?

I'd give you a day or 2 on the house just to fix that area around the door

Xcellor

https://www.boards.ie/discussion/comment/119012728#Comment_119012728

He's supposed to be over this morning. The job is not completed putting aside the patio. So will be discussing how he is planning on resolving it.

There are two sets of double doors at the back..

I'm in Longford area.

hesker

Did you read the advice above that pointed out min 150mm above dpc.

Do you know where your dpc is? Do you know why 150mm is required

Xcellor

https://www.boards.ie/discussion/comment/119013169#Comment_119013169

Not sure where DPC is - I'd assume having resting water above this would potentially give water ingress. The house was built 2006 standard block with cavity if that gives any indication.

muffler

https://www.boards.ie/discussion/comment/119012952#Comment_119012952

If and when he does appear see how you get on but if he says you're being overly fussy or argues that the drainage as it is now will work well then show him a few of the posts in this thread. Without giving too much away I can tell you that quite a few professionals have commented here and are all in agreement that the patio will have to be completely redone.

hesker

I provided a link that will allow you to get up to speed before talking with this guy. Suggest you read it as it contains very clear info.

Your dpc usually is positioned where the main render begins. The link will give you pointers on how to check. 150mm is required to prevent saturation of the block work above dpc from splashback off the patio as far as I recall reading up on it.

Xcellor

https://www.boards.ie/discussion/comment/119013218#Comment_119013218

Currently he's here. We had a discussion. I have demonstrated the problem. He talked about putting french drains in. I mentioned this was a requirement regardless based on building regs.

He's going around with spirit level and tape measure at moment.

Unless an earthquake happens and alters that earth crust -- all he is doing is confirming what everyone already knows.

Xcellor

He's started lifting the slabs.

Xander10

https://www.boards.ie/discussion/comment/119013632#Comment_119013632

are the slabs flat on the existing path?

muffler

https://www.boards.ie/discussion/comment/119013632#Comment_119013632

Result ... hopefully!

muffler

https://www.boards.ie/discussion/comment/119013534#Comment_119013534

Keep us posted please.

Maybe there are some genuine construction workers still around.

Xcellor

https://www.boards.ie/discussion/comment/119013677#Comment_119013677

Hmm will see. He tried to deny a problem initially. Saying that when the hardcore was down the drainage was perfect and there were no issues. I then felt required to explain that slabs on top of sand and hardcore is quite different. Benefit of doubt is dwindling fast... But at least the action of taking up the slabs is an admission of a serious problem.

sydthebeat

make sure a fall of min 1 in 80 is provided away from the house walls.

AND make sure an ACO drainage channel is provided for the full length of the area that the patio meets the walls, something like their Multiline Sealin product

CreadanLady

You say he put a slotted flexi land drainage pipe under the slabs near the house. And slabbed over them. Like, how was he expecting water to drain into them, unless he laid sponges as slabs. Those pipes are weak as fook too, so your slabs would all eventually crack over the line of the pipe.

He is either a chancer, or just pure thick. Both most likely.

We as it was said above, he has started lifting the slabs, so that is effectively an admission of fault now. So you have him over a barrel. I suggest you make the most of it now and give him absolute hell. Claim to caused some other damage or cracks or whatnot.

hesker

For all the architects and engineers on here what about the 150mm below dpc

Can this be ignored ?

Why all the focus on fixing slope and drainage if it can’t

Xcellor

https://www.boards.ie/discussion/comment/119014417#Comment_119014417

To be honest its a balancing act. I want a patio that wont flood my house and that is laid to a reasonable standard.

If he walks off the job the impact and cost would be significant. Even if i could recoup something it wouldn't cover everything.

So while I feel like giving him absolute hell... i have to be partially constrained.

Pawwed Rig

https://www.boards.ie/discussion/comment/119014482#Comment_119014482

I don't see why this would be the case unless you are paying him significantly less than the normal market rate.

CreadanLady

Ideally would be at least 150mm below floor level as a floor is usually 150mm thick or thereabouts. So just in case you had a break in the DPM under the floor, you would not want the hole in the DPM sitting in water if the place was waterlogged.

sydthebeat

https://www.boards.ie/discussion/comment/119014432#Comment_119014432

most likely the client doesn't want to step down onto the patio??

I jest, its a good question and one worth exploring.

Whilst having the patio level with the DPC line isnt the perfect detail, its not against building regulations as was previously stated.

Its considered "good practise" and a prima facia compliance with TGD C to have external ground / paving 150mm under the DPC line, but having it above isnt banned by the regulation once "The floors, walls and roof of a building shall be so designed and constructed as to prevent the passage of moisture to the inside of the building or damage to the fabric of the building" (which is the actual regulation which needs to be met)

in the industry, it is considered that this regulation is met once a proper drainage channel is located at the junction of the paving and the wall, drained away from the wall, and the paving is designed and laid to fall to drain water away from the walls as well. You will find this detail in other incarnations such as balconies, sloped access pathways, level access landings etc.

Like a lot of our building regulations, they were written very much based on the UK counterparts. It makes a lot of sense to prevent splashback onto a brick wall (which is a lot more prevalent in the UK than here) to prevent erosion of the brick, and possible freeze thaw issues. I certainly wouldn't be recommending a level patio off a brick wall for this very reason.

it should be noted that section 3.2.3 of TGD C hasnt changed in its wording since its first publication in 1991. A hell of a lot has changed in construction material and techniques in the following 31 years, plus with Part M requiring level access, the 150mm separation can never be always met anyway

mickdw

In my opinion, the lack of 150mm drop cannot be ignored and would certainly be listed as a significant issue if surveying such a property.

Since introduction of part m ramp access, houses are better detailed to cater for raised external level but still require slope away and drainage channel.

This house will likely have dpm or radon barrier raising no higher than top of subfloor. It will then have dpc just above finished floor on both blocks. This system depends on external ground level not being above the highest point of the dpm.

I'd be very afraid of this detail.

I saw a patio done before up at floor level but spaced about 300mm off from the house with a brick upstand at edge. The doorway had a black metal grille type surface bridging the gap over the entire width of the door plus alittle extra. The raised brick edge was returned to within 50mm of the house either side of the door.

The guy selling the house said he did this himself as he didn't want build up against the house but needed it flush for wheelchair.

Damp proofing wise, it was a good solution I thought. The gap was wide enough to not get blocked up and the patio was only about 2.5m either side of door.

The upstand was perfect for the wheelchair but might need to be looked at re trip hazard for able bodied people.

Xcellor

So update.

offending section of patio is being removed and a fall is being put in that will carry away from house and off to the side where a fall towards the other side of house but be drained with French drains.

Where patio meets house there will be French drains installed plumbed into drain water down pipe.

One thing is that the guy wants to run the drain in one line and not come in flush with door. Any problems with this approach?

MacDanger

Reading this with interest as we're currently getting ready to build (tender docs just finalised) and our back (sliding) door is flush with a patio area outside - is this something we need to check the design with the engineer?

Nigzcurran

https://www.boards.ie/discussion/comment/119015505#Comment_119015505

Not too sure how’s he’s hoping to fix it without lifting the whole lot of the slabs to be honest, it sounds like it’ll have multiple run offs in different directions

Xander10

Sound like he might be moving the water pooling from the patio door area to another part of the patio.

The Continental Op

https://www.boards.ie/discussion/comment/119015728#Comment_119015728

Nice to see Job's comforter is alive and well.

Xander10

https://www.boards.ie/discussion/comment/119015736#Comment_119015736

Not sure what you mean . But if the advice from those in the know, is that all the slabs should be taken up and redone, then the option offered of redoing part of the slabs doesn't sound a good fix.

But carry on with whatever comments you want to make.

sydthebeat

https://www.boards.ie/discussion/comment/119015736#Comment_119015736

I dont see xanders comment as being anything but negative to what the contractor is suggesting.