Burnt sand mastic & UPVC

[Kilt]

I’ve been led to believe that burnt sand mastic is detrimental to upvc, and shouldn’t be used. 
however I’m struggling to find any factual basis to back this up.

 

does anyone know if this is true?

 

I’m trying to marry up old wonky stone work and seal some newly installed windows. 
 

[markc]

I’ve never heard this and can’t imagine why it would or could be true

[TonyT]

Just buy the ready made version of trowelling mastic .  
 

You don’t want to ruin the oven?

[Kilt]

1 hour ago, markc said:

I’ve never heard this and can’t imagine why it would or could be true

I’m assuming it’s the oil, if some of the ready-mix stuff use petroleum oil, rather than a natural base like linseed.

Purely speculating. 
 

The only thing I’ve found is on a Everbuild Site for their trowel mastic, which states:

”LIMITATIONS
▪ Unsuitable for plastic frames heat absorbing glass.”

 

but that’s petroleum based. 

Edited October 19, 2021 by Kilt

[markc]

24 minutes ago, Kilt said:

I’m assuming it’s the oil, if some of the ready-mix stuff use petroleum oil, rather than a natural base like linseed.

Purely speculating. 
 

The only thing I’ve found is on a Everbuild Site for their trowel mastic, which states:

”LIMITATIONS
▪ Unsuitable for plastic frames heat absorbing glass.”

 

but that’s petroleum based. 

I can see trowel mastic being a problem but that has a very specific use.

when you think about it, most cars have panels and trim bonded with mastic, and mastic is also used for sealing rainwater goods etc.

a quick check of the particular data sheet should avert your fears

[Kilt]

14 minutes ago, markc said:

I can see trowel mastic being a problem but that has a very specific use.

when you think about it, most cars have panels and trim bonded with mastic, and mastic is also used for sealing rainwater goods etc.

a quick check of the particular data sheet should avert your fears

Masons-mortar use 'Rosin oil' in their burnt sand. Sadly no data sheet, so will give them a call later today.

 

Not come across 'Rosin' before, but a terrible google search pulls up not to use on plastic due to leaching (which I guess it damaging plastic), but that's if you're planning on eating the Rosin!

[markc]

22 minutes ago, Kilt said:

Masons-mortar use 'Rosin oil' in their burnt sand. Sadly no data sheet, so will give them a call later today.

 

Not come across 'Rosin' before, but a terrible google search pulls up not to use on plastic due to leaching (which I guess it damaging plastic), but that's if you're planning on eating the Rosin!

Ahh yes Rosin is definitely not good for plastic.

that’s why you should never put one of those car air freshener things onto your dash or centre consul …. The plastic or vanilla gets eaten away. Luckily mastics and sealers are rarely rated on their fresh mountain odour ?

[Kilt]

5 minutes ago, markc said:

Ahh yes Rosin is definitely not good for plastic.

that’s why you should never put one of those car air freshener things onto your dash or centre consul …. The plastic or vanilla gets eaten away. Luckily mastics and sealers are rarely rated on their fresh mountain odour ?

I talked to Masons Mortar and they said no, can't be used with UPVC.

 

I have been trying to avoid using cement on the property (18th Century, lime etc) but at this time of year, don't really know what the options are to fill the 2-30/40mm gaps.