rendering

[christ]

been skimming for about 4 months now, havnt done any flat rendering, fancy doing a bit, can anyone explain how its done. cheers

 

[bodplasterer]

Rendering is completley different to skimming best way to learn is to work with a spread who can teach you. But the basics would be lay on a scratch coat 4:1 sand and cement with waterproofer then it has to cure for at least 24 hrs even better 48 hrs then top coat with 5:1:1 the extra 1 is lime. Try taking the high spots of with a darby then float it up with a fiberglass float you may need to float it twice then what i do is flatten it with a trowl then sponge by rotating in a circular motion.

 

[christ]

do you have to soak the sctach coat with water first, using hosepipe?

 

[bodplasterer]

On a hot day it is advisable or a large area but if the waterproofers doing its job theres not much need, just try an area by flicking a bit of water and if it rolls off then you should be ok but if it soaks it up then give it a full blast of water.

 

[christ]

do you have to seal the surface u'll be renderning with pva first, also how do you attach the stop bead to brick or block?

 

[bodplasterer]

Brickwork is usually more porous so you can seal it, I think unibond make an external pva you can also use sbr with cement as a slurry, but on blocks your fine to render straight onto unless its durox or thermalites them you need to put riblathe on. As for beads common practice is to put a bellcast bead around the dpc line and above windows and just use external angles for the corners if the reveals are tight use stops plus use stop beads if you need to stop your render anywhere like between houses (stainless are better for external but very pricey)

 

[christ]

cheers bod for info, seems like theres alot more to rendering, than skimming. think ill read a bit more about it before i have ago myself.