Linear drain - shallowest?

[NFI]

I´m looking to install linear drain around the top edge of a staircase to a first floor tiled terrace. Rainwater currently drains down the steps, causing damp and peeling paintwork in the open area below. The terrace is built on a reinforced concrete bed. I considered a bund around the top of the steps but that´s just a massive trip hazard. I´m a bit concerned that if I cut down too far into the concrete I´m going to start hitting rebar and causing all sorts of problems for myself. The shallowest drain I´ve found is 80mm deep from Aco. Does anyone know of a shallower one, or indeed could suggest a different method?

[Dave_L]

Any chance of a picture of the problem area NFI?

I can't think of a linear channel that's any shallower.

[lutonlagerlout]

STOP
do not cut into reinforced concrete without a structural engineer's advice
dangerous and foolhardy in the extreme
there is probably a different way to look at this problem
picture please
LLL

[GB_Groundworks]

as mr lout said don't go cutting your reinforced slab is that way for a reason to carry your terrace. can you resurface the terrace and either lay a u shaped channel or make one to take the water away out of concrete with some gutter pressed into it to make a reserve shutter to form the channel?

[Tony McC]

Notwithstanding M'learned colleague's comments regarding the folly of breaking into a RC structure, there is a shallow linear channel by the name of Deckline which can be obtained at a healthy premium from Messrs Aco of Hitchin in the county of Hertfordshire. Invert depth of just 50mm; overall depth of 60mm - you'll not get much shallower than that!

[NFI]

Thanks for the advice and the quick replies. Links to pictures below. A few points to clarify:

The terrace is 5m * 5m, tiled all over. I´d rather not re-lay it!

Reinforced slab is approx 125mm thick.

I was hoping to simply chip away the top 30-40mm of concrete, without (hopefully) hitting the rebar, along a length of no more than 1.5m in each direction (see photo), right at the edge of the reinforced slab where it meets the steps down. Would this still be a structural issue?

I had thought of a very shallow cement ´dish´ at the top edge of the steps, draining through the terrace wall in a bit of 40mm pipe, but was looking for a product to make it look a touch nicer.

Edited to add links to pictures (I Hope)


Regards,

NFI

Terrace picture1

Terrace picture 2

[nick65]

Theres a company called Riolito who do a 50mm linear drain.
I think there for shower floors,but they may help.

[Tony McC]

Admittedly this is guessing, but with my 30+ years of experience of rc structures, I'd expect there to be 'corner bars' (90° shape) close to that step edge and so by removing concrete at that location, you run a very high risk of exposing the steel or, at the very least, of reducing the amount of cover (which protects the steel from fatal oxidation) to an unacceptably thin skin.

I'd strongly urge you to seek on-site advice from a structural engineer.

[NFI]

Again, thanks for the help. Can anyone suggest another way of containing and channeling the runoff?

[Pablo]

Bit of lateral thinking would you have room to build a new set of steps on top of the old ones that way you could extend the top tread out by one and include the channel in the tread or better still a slit drain. A kickboard type bit of stainless steel or something similar under the handrail to stop water going over there would maybe be a solution to that problem. You would need to be sure the old steps could handle the weight of the new ones. Just a thought could be talking rubbish.

[seanandruby]

photo would be nice

[GB_Groundworks]

they are linked above but for easier viewing here they are for the poster

[NFI]

Thanks for posting the pictures GB. I couldn´t get the system to do that.