How to finish basecoat

Cornelius

Well-Known Member
How do you guys leave your basecoat ready for silicone topcoat 1.5mm? I’ve been using Krend basecoat and was just wondering how best to leave it ready to receive the topcoat? Is just a spat flat sufficient? Sponge? Normally I’m happy to just leave it spatted off ready for primer and topcoat. Enjoying using the bagged renders more and more these days but my techniques are still evolving. So far I’ve used pro rend, Weber, parex, knauf and krend. Prefer the Weber myself.
 
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1st coat on rule off serrated spat embed the mesh second coat on quick spat then sponge over it when ready ,
What type of sponge you using? Often find the sponge drags a bit, probably wrong timing. I’m same as you lay on, rule with serrated edge , bed in mesh , tight skim over the top of mesh and spat it in. Not perfected my sponging technique, been using sponge floats and also standard car wash style sponge. Just seems pointless to get primed over then finish coat aswell.
 
What type of sponge you using? Often find the sponge drags a bit, probably wrong timing. I’m same as you lay on, rule with serrated edge , bed in mesh , tight skim over the top of mesh and spat it in. Not perfected my sponging technique, been using sponge floats and also standard car wash style sponge. Just seems pointless to get primed over then finish coat aswell.
Yes i no what youre saying.. i use the refina ones you get three in a pack got them from wack wholesale.
Its a pain with this weather as its drying quicker in places.
I dont think you can go much wrong with that system.
Hoping to try thefassa bortolo next couple of weeks
 
Yes i no what youre saying.. i use the refina ones you get three in a pack got them from wack wholesale.
Its a pain with this weather as its drying quicker in places.
I dont think you can go much wrong with that system.
Hoping to try thefassa bortolo next couple of weeks
So is it a fine sponge then? Not the medium or coarse. What is fassa bortolo?
 
To be fair its not to soft. Its another brand of render its italian ive been hearing good things about it .. some say its the whitest render you can buy? They do mono and silicone .

Got a couple of render jobs lined up not as pleasent with this heat though but it beats cold.
 
It gets a bit confusing all the different brands and systems and strange codes for products. The guys on here I haven’t got a clue what they’re talking about half the time. I like Weber but often a job will have a specific spec. So the materials change slightly. To my knowledge British gypsum not on the bagged render scene?
 
Just saw something on YouTube about using a diamond float? I’m probably getting mixed up now?
 
Webers nice gear to youse i like it too..
I no gets as crazy as the trowel scene.
Ye saint gobain own weber so there there just rebranded.
 
Thin coat renders can be a pain. As above, serrate edge, mesh, thin layer over spat smooth. You can then sponge but it either leaves a scoured finish which will possibly need a good scrape when set or it tears all over!

I now have the knack of a smooth spat finish then scrape any lines smooth with a carborundum stone.
 
Thin coat renders can be a pain. As above, serrate edge, mesh, thin layer over spat smooth. You can then sponge but it either leaves a scoured finish which will possibly need a good scrape when set or it tears all over!

I now have the knack of a smooth spat finish then scrape any lines smooth with a carborundum stone.

me and the bulgarians use back edge of the trowel sounds great at 07.30 in the morning on the flats we working on like scraping your finger nails down the blackboard the residents love us.(not)
 
Thin coat renders can be a pain. As above, serrate edge, mesh, thin layer over spat smooth. You can then sponge but it either leaves a scoured finish which will possibly need a good scrape when set or it tears all over!

I now have the knack of a smooth spat finish then scrape any lines smooth with a carborundum stone.

Not done much thin coat myself , but found using a wet medium Regina sponge and a spray with water stops any tearing then a spat over the fat leaves a nice and flat finish.
 
Thin coat renders can be a pain. As above, serrate edge, mesh, thin layer over spat smooth. You can then sponge but it either leaves a scoured finish which will possibly need a good scrape when set or it tears all over!

I now have the knack of a smooth spat finish then scrape any lines smooth with a carborundum stone.
Yeah scoured finish is spot on way to describe it, I end up putting the trowel over it later on when it’s set a bit
 
Yeah scoured finish is spot on way to describe it, I end up putting the trowel over it later on when it’s set a bit

I had a very experienced lad do me a permarock job. That stuff was very gritty and scoured heavy. But silicone over was fine. Probably a good key.
 
It is surprising what the silicon covers, considering it’s scraped on so thin it seems to hide quite a lot.
 
I had a very experienced lad do me a permarock job. That stuff was very gritty and scoured heavy. But silicone over was fine. Probably a good key.

when ever we have done an acrylic finish for Permaroc it has been a bark finish.
 
Sorry to hijack thread but finally I have a thincoat system to do, hp12 embedded in mesh then tc15 top coat. What's the crack with beads ? Do you just use 6mm beads and what do you fix them on with. Builder I'm doing it for knows I've not done it before but quite happy for me to crack on, waiting for k-rend to get back with a spec, any additional help would be much appreciated, cheers..
 
Depends on how thick you are putting the hp12 on?

6mm thick 6mm beads etc.

I stick mine on with thin coat material. Some us Gripfill.
 
Cheers for reply Rigsby, total novice at this, builder says it's 6mm so do i finish base with mesh flush to beads, then primer then tc.
Can i stick beads with hp12 or is there a better method? Cheers again..
 
Cheers for reply Rigsby, total novice at this, builder says it's 6mm so do i finish base with mesh flush to beads, then primer then tc.
Can i stick beads with hp12 or is there a better method? Cheers again..

What are you applying HP12 to?
 
It's on an approved cement particle board, hp12 embedded in mesh to 6mm, leave for minimum 14 days then primer, then top coat 2mm.
 
Depends on how thick you are putting the hp12 on?

6mm thick 6mm beads etc.

I stick mine on with thin coat material. Some us Gripfill.
Rigby, cheers for your help before, not had a chance to be on here. Job turned out great in end, nice learning curve, only downside was before I got there they nailed beads on for me, probably would have been better bedded on.
I like the finish of the render but takes a long time to set , I'm assuming it's quicker setting on block background? Builder I am working for has a house to do soon which will be onto block. Can i get away with 10mm beads, hp12 fully meshed then top coat? Thanks
 
Think you will find the manufacturers will spec a 15mm render for block.

K Rend does an ocr. You can do a conventional 2 coat if you are hand applying.

Mesh on new block usually only warrants stress patches. Check what newton the blocks are and if they are below 7 newton get a manufactures spec.

Depending on who’s ocr will depend on what suction you will get. But bear in mind now the air is damper your blocks will have absorbed damp.

If you do 2 coat and your chosen ocr has a waterproofer in it then use an accelerator. Your ocr manufacturer will probably make one or use Wickes. If it is cold (below 10c) then there are other options on how to get ocr on with only 8 hrs of light but thats going to go into a lot of in depth writing and I have a banging headache!

If you want to go down to 10mm its at risk of the blocks showing through. But a good silicone might cover this.

Jub Carbon Base ocr is good for 10mm.
 
Think you will find the manufacturers will spec a 15mm render for block.

K Rend does an ocr. You can do a conventional 2 coat if you are hand applying.

Mesh on new block usually only warrants stress patches. Check what newton the blocks are and if they are below 7 newton get a manufactures spec.

Depending on who’s ocr will depend on what suction you will get. But bear in mind now the air is damper your blocks will have absorbed damp.

If you do 2 coat and your chosen ocr has a waterproofer in it then use an accelerator. Your ocr manufacturer will probably make one or use Wickes.
Think you will find the manufacturers will spec a 15mm render for block.

K Rend does an ocr. You can do a conventional 2 coat if you are hand applying.

Mesh on new block usually only warrants stress patches. Check what newton the blocks are and if they are below 7 newton get a manufactures spec.

Depending on who’s ocr will depend on what suction you will get. But bear in mind now the air is damper your blocks will have absorbed damp.

If you do 2 coat and your chosen ocr has a waterproofer in it then use an accelerator. Your ocr manufacturer will probably make one or use Wickes. If it is cold (below 10c) then there are other options on how to get ocr on with only 8 hrs of light but thats going to go into a lot of in depth writing and I have a banging headache!

If you want to go down to 10mm its at risk of the blocks showing through. But a good silicone might cover this.

Jub Carbon Base ocr is good for 10mm.
hi rigsby people telling me your the man in the know so could you advise me on my home project iv got a plasterer whos going to k rend the top half of my house hes taken the old pebble render off i and have dark rough cinder block underneath hes telling me, primer, hpx base with mesh, 15mm bead, then askes me what top coat you want ,k1 , or ft ????????? and what colour ??? whats the difference and any advice on nice colours youve used any info would be great thanks
 
Sounds right. But as to K1 or FT thats down to personal choice. I take it you are having a monocouche render finish. K Rend products are good but their K1 monocouche has a reputation for being problematic. Mainly cracking issues. More to do with the product than applicator error.

For better peace of mind consider a 15mm render finished in a silicone. Less chance of cracking and will keep cleaner and colour fast.

If you do have monocouche I recommend as light as possible. Preferably a colour that is kept in stock.
 
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