Hi paving experts.
So i have recently completed a fossil mint patio (on the weekend), which looks great. The patio is at my own house, it is not yet pointed, layed on a fresh concrete slab, with a bedding mix of 4:1:1 stone dust, sand, cement with pleanty of waterproofer and plastisiser.
However, when reading about sealing and effervescent I came across reflective staining. I am now concerned that I didn't lay on a completely solid bed of mortar, but a very generous dotted bed and a ring. I also only coated with a good PVA (i now know SBR slurry in hindsight). I have laid a number of Green Raj patios this way with no issues, but the spunge like quality of the mint is causing me concern.
I am looking for advise, do I apply a preemptive coat of permeable sealer when the weather turns, to prevent capillary action, or is this likely to cause other issues?
Also cement, resin pointing or cango?
Happy slabbing, thanks in advance Welshhero
Did i balls up my fossil mint sandstone - Sealing to prevent reflective staining
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dig dug dan
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Why waterproofer and plasticiser? And why pva? And why no full bed?
Mint fossil is the worst slab to absorb spills, algae bbq fat etc, so it would have to be sealed somehow, just not sure you wont have along term problem if its not been laid correctly.
You may want to leave it to see if the slabs have fully bonded before you start pointing in case it has to come up and be re laid
Mint fossil is the worst slab to absorb spills, algae bbq fat etc, so it would have to be sealed somehow, just not sure you wont have along term problem if its not been laid correctly.
You may want to leave it to see if the slabs have fully bonded before you start pointing in case it has to come up and be re laid
Dan the Crusher Man
01442 212315
www.crusherhire.co.uk
"a satisfied customer? we should have them stuffed!"
01442 212315
www.crusherhire.co.uk
"a satisfied customer? we should have them stuffed!"
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Welshhero
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- Joined: Wed Apr 29, 2020 11:06 pm
- Location: Wales
Unfortunately I didn't do my research before laying, and im just a DIY'er who enjoys the work. I have done a few of my own patios before with no problems but using much better slabs.
The seller specifically told me not to seal untill all the salts had come out, which I now know is poor advice. It seems the best advice would have been buy something else.
I used the PVA simply for priming the stone and additives for durability and workability. I am not overly concerned about the spot bedding because it was very generous applied and compacted that I am confident most will have a full bed.
The advice I am after is will properly sealing the stones early prevent wicking of bedding mix, or is this likely to make the situation worse.
The seller specifically told me not to seal untill all the salts had come out, which I now know is poor advice. It seems the best advice would have been buy something else.
I used the PVA simply for priming the stone and additives for durability and workability. I am not overly concerned about the spot bedding because it was very generous applied and compacted that I am confident most will have a full bed.
The advice I am after is will properly sealing the stones early prevent wicking of bedding mix, or is this likely to make the situation worse.
Welshhero
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Tony McC
- Site Admin
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- Location: Warrington, People's Republic of South Lancashire
- Contact:
PVA - water soluble so a complete waste of time and money on any project where it is used in near permanent damp conditions.....such as paving!
The spot/ring bedding is very naughty and you should be pelted with nuggets of cow dung by nubile virgins for committing such a heinous offence. It is very, VERY liklely, almost a certainty, that you will get reflective staining on that godawful Mint skip-filler over the next 2-3 months. Applying a sealant will simply seal in the problem and do sweet FA to prevent it. In fact, it's a waste of money because the flags are likely to be ruined by reflective staining, so why spend yet more money on a sealant when you may well have to replace the flags?
The seller was, technically, correct in advising stone should not be sealed until there has been adequate time for salts and other minerals to vent and weather-out, but with some of these highly vulnerable stones, such as Mint, Rainbow, Teak, etc., the risk of stain damage during installation is so high (regardless of how careful is the installer) that pre-sealing is becoming commonplace. It can, with some stones, bring its own problems, but it's a judgement call: only the installer can decide what is best.
All you can really do for now is sit back and wait for the inevitable to hit the fan...and then see what's the best thing to do to rectify: allow it to weather over 3-4 years or rip it up and start again, armed with all this wonderful new knowledge.
The spot/ring bedding is very naughty and you should be pelted with nuggets of cow dung by nubile virgins for committing such a heinous offence. It is very, VERY liklely, almost a certainty, that you will get reflective staining on that godawful Mint skip-filler over the next 2-3 months. Applying a sealant will simply seal in the problem and do sweet FA to prevent it. In fact, it's a waste of money because the flags are likely to be ruined by reflective staining, so why spend yet more money on a sealant when you may well have to replace the flags?
The seller was, technically, correct in advising stone should not be sealed until there has been adequate time for salts and other minerals to vent and weather-out, but with some of these highly vulnerable stones, such as Mint, Rainbow, Teak, etc., the risk of stain damage during installation is so high (regardless of how careful is the installer) that pre-sealing is becoming commonplace. It can, with some stones, bring its own problems, but it's a judgement call: only the installer can decide what is best.
All you can really do for now is sit back and wait for the inevitable to hit the fan...and then see what's the best thing to do to rectify: allow it to weather over 3-4 years or rip it up and start again, armed with all this wonderful new knowledge.
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