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Posted: Tue Jan 15, 2013 7:37 pm
by joydivision
I have a cavity wall parapet to build and looking for options of how to capping it.
The parapet will run at a pitch, (not sure what degree yet) but will follow the roof pitch although higher to allow the lead flashing from the roof to be incorporated.
Is using dpc ok under the coping? When I have done them in the past it has been for a company who supplied coad 4 lead.
Also I think the lead/dpc whichever is used, will have to sit directly under the coping due to height restrictions of the parapet. Is there a better way of bonding the copings to the dpc/lead than using mortar. Im having concernes about the copings not adhearing very well to the dpc/lead and coming lose, and with it being on a pitch they may slip even easier.

Thanks

JD

Posted: Tue Jan 15, 2013 9:39 pm
by GB_Groundworks
weve just done one with a 400mm flag with a drip cut into it and then a double saddle back coper on top of that, wasnt ideal but it worked

we used 6inch dpm under the copings and had a cavity tray ontot he top of the asphalt tanking under the coping as well

all bedded with a strong sbr mortar

this was the original design which was pointed out to the architect wouldnt work as no drip....

Image

so we did it and the walls got wet so we had to remove them and do it like this

Image




Edited By GB_Groundworks on 1358286080

Posted: Wed Jan 16, 2013 2:36 am
by lutonlagerlout
we had to do something similar here JD
Image
the lead was bedded onto the internal blockwork 50mm and then the copings laid on that
bugger me they are heavy 400mm wide and 900 mm long saddle back they must weigh 50kg each
its a double hander laying them but they do the job and the weight hold the lead on well
cheers LLL

Posted: Wed Jan 16, 2013 8:54 am
by GB_Groundworks
we did a fountain once out of pre cast stone stuff and that all had to be pinned and epoxied with stainless steel dowels, what a PITA that was

Posted: Wed Jan 16, 2013 7:47 pm
by joydivision
Think thats all you could have done without buying new copings to be honest Gilles. Architects hey!
I would like to put a tray dpc in the job im talking about, but dont have the height to do so.

LLL, thats pretty much a replica of the job I am talking about. From your photo, im thinking our roof line will be 150mm lower than the pitch, lead flashed up and onto the blockwork, then leaded across the cavity.
I also have used them big 900mm buggers myself in the past, no fun getting them up either!! They wont be going on this job though.

Cheers

JD

Posted: Wed Jan 16, 2013 7:57 pm
by lutonlagerlout
exactly
the only other alternative is to use slat to bridge the cavity then tile creasing or something
i spoke to a rep and he said cut them in half
I was the only bloke on the job that could carry them up the ladder,maybe more than 50kg,i dunno but bleedin heavy
LLL

Posted: Wed Jan 16, 2013 8:34 pm
by GB_Groundworks
i carried 28 of them up the ladder to the lads on teh balcony wasnt a fun day