Sagging, sopping wet sand cement in 1 area

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loky11

Well-Known Member
Just rendered an extension but 1 area was sopping wet literally like piss and kept slumping, wasnt on thick at all in fact was probably the thinest part of the render, scraped it off and put fresh stuff on, every where else was spot on but this 1 particular area. Does any one know what causes it ? Cheers
 
Just rendered an extension but 1 area was sopping wet literally like piss and kept slumping, wasnt on thick at all in fact was probably the thinest part of the render, scraped it off and put fresh stuff on, every where else was spot on but this 1 particular area. Does any one know what causes it ? Cheers

Where abouts was it in relation to the building?
 
No suction, low temp cold spot, contaminated with water replant , block soaking holding to much water ?
 
No suction, low temp cold spot, contaminated with water replant , block soaking holding to much water ?

Feck knows mate, scratch coat was all sound like i said every where else was spot on floated and sponged nicely apart from this certain area that would not go off.
 
Feck knows mate, scratch coat was all sound like i said every where else was spot on floated and sponged nicely apart from this certain area that would not go off.

I've had it a few times, usually external in winter, if scratch coat flick a bit of cement on it and leave it long as possible b4 flatten, but float coats a pain, scrape and dry wall with newspaper and slightly stiffer gear on and leave long as poss b4 rubbing up, sponge will take some water out early on.
 
I've had it a few times, usually external in winter, if scratch coat flick a bit of cement on it and leave it long as possible b4 flatten, but float coats a pain, scrape and dry wall with newspaper and slightly stiffer gear on and leave long as poss b4 rubbing up, sponge will take some water out early on.

Its a pain in arse, i managed to gently float it, couldnt sponge as way too wet and dont fancy hanging around till midnight, so im hoping i can give it a hard float early morning.
 
Was scratched on friday so wasnt bone dry some areas had dried but not all of it. Didnt hose down, just whacked it on as it was only a small area.

Im guessing then just an area that may have taken up some water in the blockwork and scratch coat and was just sitting on the surface.

Ive had it before where gone from blockwork to bricks.

Could even be an area with to much waterproofer in the mix possibly?
 
Im guessing then just an area that may have taken up some water in the blockwork and scratch coat and was just sitting on the surface.

Ive had it before where gone from blockwork to bricks.

Could even be an area with to much waterproofer in the mix possibly?

When i scraped it off it was soaking, i wiped it down with a sponge before putting fresh stuff on, this stopped it from sagging but still wasnt nippin up.
 
Another quick question, will this effect how well top coat keys to scratch coat? Really dont want it blowing.
 
Once cold months come in I stop layingl before 2pm, had one patch couple years back hanging for hours, I even put lamp up to it for heat to dry it a bit, but was ok next morning and rubbed in well.
 
When i scraped it off it was soaking, i wiped it down with a sponge before putting fresh stuff on, this stopped it from sagging but still wasnt nippin up.

Ive had the same problem before exactly like you have described.

And this was even in the summer!
 
Another quick question, will this effect how well top coat keys to scratch coat? Really dont want it blowing.

I've got into habit that an old plasterer I worked with did, wet down with paddle brush with sbr in the water, not sure why he did it but not had any blow so far, touch wood.
 
It can if it has been pushed and pulled about too much.

Oh hell, thats what i dont want to hear, but thanks for the info, will see how it is in morning, will have to patch it if necessary, not ideal i know but under the circumstances i dont know what else to do.
 
The maternal instinct
More like the nosey b*****d instinct!

Hey Jo, look what I’ve achieved today!! Dropped this screw from the ceiling and landed it like a ninja with an arrow! Massive chuffties happening here in fallowfield!!
:numberone:

image.jpg
 
I did a dashing job December 23 1989. Out of the whole job I had a 1m2 area that not only remained wet but seemed to get wetter. Dashed the wall at around 10.30am but this particular patch was still wet at 3pm! Going dark so managed to get it done after blotting it with loads of newspapers.

But out of curiosity I called by next morning and it was still wet! Not enough to be able to dash but not set. Every where else was set.

I can only think water was running out of the mortar and ended up in one spot. I drive past this property most days as it’s in my neighbourhood and is still there but never had a job like it since.

Wavy scratch and wire comb.
 
I did a dashing job December 23 1989. Out of the whole job I had a 1m2 area that not only remained wet but seemed to get wetter. Dashed the wall at around 10.30am but this particular patch was still wet at 3pm! Going dark so managed to get it done after blotting it with loads of newspapers.

But out of curiosity I called by next morning and it was still wet! Not enough to be able to dash but not set. Every where else was set.

I can only think water was running out of the mortar and ended up in one spot. I drive past this property most days as it’s in my neighbourhood and is still there but never had a job like it since.

Wavy scratch and wire comb.
Wonder if it’s dried out now!
 
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