bassanclan Posted March 2, 2017 Share Posted March 2, 2017 After looking at lots of alternatives for render we decided that the need for a smooth finish and the desire to have an ashlar groove effect (like houses from Leamington Spa etc) meant we chose sand and cement render. The S&C is then to be painted cream colour with a self cleaning paint e.g. Sto Lotusan The renderers have marked out the "blocks" using upvc beads, sticking them on with silicone. The beads and the silicone are white. Today I realised that the paint won't stick to UPVC and virtually no paint will stick to silicone (which has inevitable squeezed out into the groove of the ashlar when sticking the beads on). Any bright ideas? Link to comment Share on other sites More sharing options...
Russell griffiths Posted March 3, 2017 Share Posted March 3, 2017 Right I'm no expert but I have built a house that had pvc edge beads and was painted afterwards. We used a scotch bright pad and normal sandpaper to rough up the beads before we rendered, we did not have any problems with an acrylic exterior paint sticking to it, apart from if it took a big hit from something. As as for the silicon I think you will need to get a stanly knife out and do a lot of rubbing with your finger. It does come of pvc very easily just going to take a while. How big are the gaps between the beads? Is this where the silicone has popped out? Like the look of the bricked up window? Its too late now for you but for for anybody else reference you can get a special spray adhesive just for pvc trims. Link to comment Share on other sites More sharing options...
Brickie Posted March 3, 2017 Share Posted March 3, 2017 Why on earth didn't they mark the joints into the render a la Ashlar Markings system?? Link to comment Share on other sites More sharing options...
bassanclan Posted March 3, 2017 Author Share Posted March 3, 2017 There is a 15mm joint between the beads. We considered laying on the topcoat of render and then cutting out the ashlar grooves, but the renderer thought it would be harder to do. Also you only get one chance to get it right! The beads could have been nailed on, but then water could get behind the bead and hence topcoat and then freeze and blow. I think I will have to scrape off the silicon, scotchbrite the pvc, prime the pvc, fill any gaps etc with a non silicone caulk, then paint Link to comment Share on other sites More sharing options...
bassanclan Posted July 13, 2017 Author Share Posted July 13, 2017 The rendering saga drags on. After scraping all the silicone out the joints, the contractor has rendered the whole house, but it has taken longer than he expected. There are a few areas for snagging, such as patching up and squaring up some reveals and heads, but he's walked off the job. Am I being too picky? Is there an acceptable tolerance for render e.g 10mm in 5m etc? Link to comment Share on other sites More sharing options...
Declan52 Posted July 13, 2017 Share Posted July 13, 2017 You have used beads to give nice straight edges on all the joins so why is there none used on the reveals. Takes no time to bond the bead on nice and plumb, same goes for across the opening. No matter what way you fix it it will be noticeable. The bit that's burst out Def needs fixed, the rest hard call to make as it might look worse unless it's painted over to hide the different mixes Link to comment Share on other sites More sharing options...
bassanclan Posted July 13, 2017 Author Share Posted July 13, 2017 I don't know why they didn't use beads on the heads and reveals. I'm not happy as it is, I've found someone that knows how to form wet external freehand corners who has done a lot of work on conservation buildings etc, so hopefully he can sort it out Link to comment Share on other sites More sharing options...
Brickie Posted July 14, 2017 Share Posted July 14, 2017 I'd have said the heads wanted a detail,to give the impression of a stone head spanning the opening,rather than just following coursing lines to give that split block effect as there is in the photo. If you could live with that projecting say 10mm then maybe you wouldn't need to hack off the work that's done,but merely add the detail in an extra coat. Same with the reveals-is there enough play to have a quoin detail? Link to comment Share on other sites More sharing options...
iSelfBuild Posted July 14, 2017 Share Posted July 14, 2017 Can you not just spray the beads with plastic etching primer then paint over them with your paint? Link to comment Share on other sites More sharing options...
bassanclan Posted July 14, 2017 Author Share Posted July 14, 2017 45 minutes ago, iSelfBuild said: Can you not just spray the beads with plastic etching primer then paint over them with your paint? The etching primer instructions generally say to abrade the surface with sandpaper/scotchpad etc to get the shine off the upvc. This would take a decent amount of time. I would also need a clear coloured etch primer and have to hope it didn't attack the surrounding render (I presume it contains acid) Link to comment Share on other sites More sharing options...
bassanclan Posted July 20, 2017 Author Share Posted July 20, 2017 So a couple of renderers came to look at how to fix it. Neither were willing to give a price because they didn't know how much work would be involved once they started hacking of the dodgy areas. So I paid a surveyor to come and give an expert opinion - £5000-£7000 to fix it! Link to comment Share on other sites More sharing options...
Onoff Posted July 20, 2017 Share Posted July 20, 2017 EWI? Link to comment Share on other sites More sharing options...
jack Posted July 20, 2017 Share Posted July 20, 2017 On 7/14/2017 at 08:37, bassanclan said: The etching primer instructions generally say to abrade the surface with sandpaper/scotchpad etc to get the shine off the upvc. Grinder + wire brush? If it works, it could be very quick. Link to comment Share on other sites More sharing options...
bassanclan Posted July 20, 2017 Author Share Posted July 20, 2017 I had intended to leave the render unpainted, but I'm now going to give it a coat of cream self cleaning paint (after priming the beads). I can't do much until I get the repairs done Link to comment Share on other sites More sharing options...
bassanclan Posted July 20, 2017 Author Share Posted July 20, 2017 i wish i had ewi, it seems pretty much any clown can throw that up, but apparently forming a freehand wet external corner is beyond the skill level of many-a-renderer Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now