D.P.C

[shiftster]

Hello,.i have just had a Marshalls registered company in to block pave my front garden and driveway,.everything looks cracking,.except one thing.When we were discussing the layout of the blocks,the D.P.C level was a concern,because the blocks were going to end up 2 courses above the D.P.C.I was advised that this would not be a problem,because all the company would have to do is paint bitumen on the wall,.which they did,.i am now concerned that this might not be ok,.could anyone put my mind at rest.The company did indeed paint bitumen on the wall,and the blocks do finish 2 courses above the blocks,i don't have any problems with dampness as yet.The blocks concerned are 6 and a half meters long,it does not puddle and the water runs away good.Any feedback would be appreciated,..cheers

[84-1093879891]

Without seeing the job, I can't give you a definitive answer, but for the paving to be higher than the dpc, I would be seriously worried.

Painting bitumen on the wall is not adequate protection, in my opinion. If they'd used a Dry Channel, or a linear drain, then I could probably live with it, but a coating of bitumen-based paint is not the same as proper 'tanking' as it is called.

Given that you've already paid a premium to use a Marshalls' listed firm (even if you didn't know it!), have you thought of asking the Marshalls' technical people for their opinion? I bet I can guess what they'll say! ;)

[shiftster]

not good,..thanks for your reply,..Is it possible to send you a digital picture of the area to see what you think?

[84-1093879891]

Yep - info AT pavingexpert DOT com

[shiftster]

i have sent through a couple of pics,hope it works

[84-1093879891]

Here's one of the piccies....



...I can see that the paving rises up to approach the threshold at the front door, as is common now because of Document M, but where is your dpc, relative to the base of the peddle-dashing?

[shiftster]

the D.P.C is in between the 3rd and 4th row of bricks,from the bottom of the pebble-dashing,......i have to be honest with you,....i'm slightly worried now..

[alan ditchfield]

Im not sure about this bitumen sealant (not come across it before)but it looks to me as if your paving is 9 inches above rec level, if Mr. MARSHALLS had done this job himself i would still be concerned. Dpc is there for a very good reason and in my opinion should not be interfeared with especially not burried. Alan.

[shiftster]

Feedback is appreciated guys,..What do you think the worst case scenario is,..is it as bad as ripping it all back out

[84-1093879891]

There are some situations on new build properties where the paving is brough up to, or just below, dpc level, in order to facilitate easy access for disabled persons (Document M). This is usually done just at the doorway, and in many cases, a special construction is used to prevent any possible problem with briding or damp penetration.

In cases where sectiond of paving are laid at a level higher than that of the dpc, then some form of tanking is normally involved, and additional measures, such are dry channels or linear drains may be used against the property to minimise the risk.

Daubing on a bit of Aquaseal, or other bitumen-based paint, is unlikely to be sufficient, and I'd want a written statement from the installer, underwritten by an insurance-baked warranty, that if any problems with damp were to be noticed in the coming 10 years, they will accept all responsibility, and pay for all repairs, including correcting the paving.

It may well be that you never have a problem, but I can't see any reason why the paving could not have been laid to the correct levels, with minor accommodations for the doorway(s).