Weber Pral M Render Issues - Help please for best way forward

JamesD

New Member
Hi All,

This is my first post here and I would be very grateful of any advice on the best way forward regarding some weber pral m render that was applied to 3 walls on a kitchen extension in August last year that has a number of issues and needs to be sorted. With better weather and longer days it is time to put it right and it would be great to hear from some of you guys who have experience with weber products.

The render is quite uneven in places. By 15mm in one area where you can just about see a pink mesh in the very centre where presumably it has been scratched back too much.

Some small holes are appearing, particularly on one corner of the property where feedback from the builder after being in contact with weber technical support advised that the mix had not been mixed enough before application.

There are also a number 'halo's' across all 3 walls.

Below are some pictures that might help.

Firstly the uneven application:
unevenrender.jpg


Secondly the holes that are appearing (pic 1):
IMG_20170419_202156.jpg


Holes (pic 2):
IMG_20170419_202225.jpg


Some of the halos: (halo 1)
IMG_20170419_202328.jpg


Halo 2:
IMG_20170419_202319.jpg


This halo above is the one that has a centre where you can just make out the mesh and has a dip of more than 15mm in the middle between the window and the corner of the wall (see below pic):
pic3.jpg


Some untidy edges:
IMG_20170419_202237.jpg


Is it a case that the whole thing needs to be taken down or is there an alternative? Could it be treated as a very expensive base layer with something added on top to hide the halo's and cover up the holes and generally improve the overall appearance?

Thanks a lot in advance for any advice given.

James
 
Wow that's bad the sun does show up slight defects but that's a joke and on such a small area that is even easier to get flat for the layman.
 
Hi flynnyman,

Thanks for the reply. This type of light does show the worst and would be hard to be perfect but I was hoping for better.

Cheers,

James
 
Hi flynnyman,

Thanks for the reply. This type of light does show the worst and would be hard to be perfect but I was hoping for better.

Cheers,

James

Thats the worst I've ever seen,must of been there first attempt,did they do any plastering inside?
 
Thanks for the reply. Inside plastering is very good. I am happy with the finish on all the work inside. It is just the render outside which really doesn't match the quality of the rest. Does it all have to come off or can anything go over the top? Thanks.
 
Thanks for the reply. Inside plastering is very good. I am happy with the finish on all the work inside. It is just the render outside which really doesn't match the quality of the rest. Does it all have to come off or can anything go over the top? Thanks.

I've a feeling they had no experience with the outside work.
To save taking it off you could use a modified base coat to flatten what's there then a thin coat render to finish.
Your adding more weight which isn't the best but really your only option.

Not sure what Webers equivalent of Parex Matie is but that's the base coat id use.

Or if your set on a monocouche finish and you've got enough overhang on the window sills etc I'd use Parex Microgobetis bonding agent then 10mm beads and Parex EHI lightweight mono to get it looking better.

Again not sure on the Weber equivalent.

Or knock it off and start again.




Sent from my iPhone using Tapatalk
 
Thanks a lot for all the advice so far.

How big a job is it to remove monocouche once it is already on? This seems like the best solution but am I right in thinking also the most costly.

Secondly, if you go over it again with something and the current base layer isn't strong enough I presume there is a risk the whole thing could come off? This would be a concern where the holes were appearing as this wasn't mixed correctly.

Thirdly, if you go over it with something what do you do with the edges? Currently there is the edging strips attached to the original brick work which the monocouche butts up to. If you add more of something on top, would you not need more edging strips and how are these bonded to the current edges?

Sorry for all the questions. I just want to make sure I'm as well informed as I can be so that when we get the work done we don't have to go back through all this again.
 
It's just fellas not knowing what they are doing, I dare say they set off with good intentions but didn't really understand the application of the product.
There's various ways of tackling it,
I wouldn't remove it, I'd put a thin coat system over the top of it.
I'd recommend you consult Weber, they'd advise further on products available as well as give you some samples.
 
If you are not bothered about the flatness you could just patch the holes with sand and cement, prime it, then spray 1.0mm silicone over the top.

Rough as f**k that...if that was my first attempt I would have re done it no questions asked.
 
If you are not bothered about the flatness you could just patch the holes with sand and cement, prime it, then spray 1.0mm silicone over the top.

Rough as f**k that...if that was my first attempt I would have re done it no questions asked.

looks like a typical "quick before it rains"
 
That looks dog s**t to me. I'd rather knock it off and start again as with that standard? I'd be dubious going over that as I wouldn't trust those other guys prep etc as your going over a potential banana skin
 
If you decide to keep it on then a thin coat system as Owls above has said.

You may get someone who could dub out the hollows a bit but it will still show some waves for 1 hour of the day.

Weber lac with a tf150 finish. Only a few mm thick and sticks like s*!t to a blanket.
 
If you decide to keep it on then a thin coat system as Owls above has said.

You may get someone who could dub out the hollows a bit but it will still show some waves for 1 hour of the day.

Weber lac with a tf150 finish. Only a few mm thick and sticks like s*!t to a blanket.
@Rigsby the render guru here
 
If you have depth on he sills and sufficient drip on the roof line.

Micro primer and 6mm beads!
As long as it is isn't blown or hollow.

I have done that process before system had yet to fail neither have I EVER rubbed through at that thickness.

The ripples aren't from the application so say, more the finish. Scraped certain areas in longer periods than others. Didn't use I bar
 
What cause these hole things on picture 2 ?
IMG_4669.JPG

Tbh I hate these threads when they pop up I always check them quickly to see if it's one of mine or @algeeman that we done
 
Powder which hasn't mixed properly. After it's been scraped instead of digging it out and putting wet scrape material in its been left. Probably next day scrape and was on the hard side to do anything with. Rain gets onto the powder drives it out
 
Without all the bullshit just take it off and go again. It's not a big job. Don't need meny bags of mono. If it was over 100m2 I'd say go over it. But looks small in the pictures.
 
Thanks for all the replies folks. Really useful. I sent pictures to Weber support and they have fully confirmed that this was due to application errors. The whole area is fairly large. It is 3 walls. The wall you can see most clearly in the photo is the smallest side.

To confirm some of the posts above, the previous attempt was applied by hand, done all in 1 day with temperatures well above 20 degrees. Yourselves and weber have confirmed that the holes are through incorrectly mixed render. The rings / halo's are through applying a 2 coat application rather than 1 which weber says is possible as long as you do not scrape through to the first which is what has happened.

Weber have said that they would advise the following:
• Brush the area down and remove any loose materials, clean with a mild detergent or biocide wash if needed, allow to dry.
• Re-set details utilising a 10mm profile bead, fix with weberend bead adhesive
• Apply weberend aid at 2-3mm and stipple using a brush or loaded roller, allow to cure for at least 48 hours.
• Apply a 10mm-12mm pass of weberpral M and finish accordingly.

I have had someone over to give advice on the job and they had suggested the same thing which was re-assuring. They were really helpful. They also said that they would use a pump rather than apply by hand and a single coat over the weberend. I like the sound of this as it would fit with webers description of a 1 coat application.

How many of you use a pump? Is a pump the way forward for a good result? If this cannot be resolved with the company that originally applied the render I want to approach other companies and I'm sure some will say they will apply by hand etc and just want to be well informed.

Thanks a lot everyone.

James
 
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Have a look at your window and door reveals to see if they will look ok with an extra 10mm on? If they will look too narrow or disappear then hack the render off the reveals.

Sprayed on imo will give the same mix throughout so even colouring.

Rendaid stippled will most likely come out onto the surface when scratched back and look like grey spots. My suggestion is key with a wire scratcher.
 
Have a look at your window and door reveals to see if they will look ok with an extra 10mm on? If they will look too narrow or disappear then hack the render off the reveals.

Sprayed on imo will give the same mix throughout so even colouring.

Rendaid stippled will most likely come out onto the surface when scratched back and look like grey spots. My suggestion is key with a wire scratcher.

Thanks for that. Very useful. Most windows look like they will be fine. A couple are cutting it pretty fine though. When you say hack back the render on the reveals what would you do with the edge. Can a new bead be added to the exposed block work after hacking back that has a thicker profile than before and then double up the mono on that part to level with the rest? I hope that makes sense.
Thanks.
 
Thanks for that. Very useful. Most windows look like they will be fine. A couple are cutting it pretty fine though. When you say hack back the render on the reveals what would you do with the edge. Can a new bead be added to the exposed block work after hacking back that has a thicker profile than before and then double up the mono on that part to level with the rest? I hope that makes sense.
Thanks.

@Rigsby just incase you missed it :D
 
If you are putting a 10mm bead on then put a coat of rendaid on the reveal substrate then stick you 10mm bead on. If you need to bring it out to the pre existing 15mm build it up with rendaid.

A good bead of silicone around the windows can hide any staining.
 
do not use this weber monocouche k rend. We were promised no maintenance, now changed to low maintenance . After a few years it is totally unsightly with red and black algae all over it. It appears cleaning at a cost of about £750 every about every 2-3 years will be required. I can send photos.
 
do not use this weber monocouche k rend. We were promised no maintenance, now changed to low maintenance . After a few years it is totally unsightly with red and black algae all over it. It appears cleaning at a cost of about £750 every about every 2-3 years will be required. I can send photos.

unfortunately that is the case... down here on the coast it does not look good very quickly. I cant believe that it was sold as no maintenance though
 
do not use this weber monocouche k rend. We were promised no maintenance, now changed to low maintenance . After a few years it is totally unsightly with red and black algae all over it. It appears cleaning at a cost of about £750 every about every 2-3 years will be required. I can send photos.
Use a quality sealer when it’s cleaned next time.
 
do not use this weber monocouche k rend. We were promised no maintenance, now changed to low maintenance . After a few years it is totally unsightly with red and black algae all over it. It appears cleaning at a cost of about £750 every about every 2-3 years will be required. I can send photos.

You could get that with any product. PFT Wales sells a product that will clean monocouxhe but if you have good insulation then the green can come back. Moisture in the cold months hangs onto the surface for 24/7 with there being low temperatures and the air moisture laden. With no heat loss this gives time for algae to grow. The North and East sides suffer the most.

You could consider a clean then treat with a Nanotechnology treatment. Weber, K Rend and Parex make them. It will help to resist the algae.
 
Wasn’t the whole idea of this stuff to save you painting, now you have to clean it and seal it, think I would rather have flat render and paint it when needs be
 
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