Fireplace Recess Prep for Wood Stove - Hearth Paint and Whether to Remove Black "Stuff"?

[slim reaper]

The mortar used in pointing is sacrificial so   should always be weaker than what its holding apart .

[topchippyles]

On 04/02/2021 at 12:26, slim reaper said:

I bought premixed pointing mortar from Ty Mawr Lime in Brecon and you can pack that in, if necessary smash small bits of stone and ram them in.

Ty Mawr Limes down in llangorse will make you a batch up and even match old colours if you take a sample down.Used then many times 

[carbs for arbs]

56 minutes ago, slim reaper said:

The mortar used in pointing is sacrificial so   should always be weaker than what its holding apart .

 

Funnily enough, I was reading an article earlier which said exactly this.  Made so much sense and seemed obvious once I'd read it, but I'd never thought of it like that...  I guess there is sacrificial and sacrificial though, and in the case of pointing it is quite a long terms sacrifice!  We're not actually pointing though, just filling a few gaps, and the main reason - which may or may not seem daft - is to stop the heat going into the gaps (would prefer it to come into the room!).

 

5 minutes ago, topchippyles said:

Ty Mawr Limes down in llangorse will make you a batch up and even match old colours if you take a sample down.Used then many times 

 

Thanks   Yes, they're on our radar for several potential jobs, like when we do the full repointing, and also if we have to lime externally once the concrete render comes off.  But because this is such a small job, and won't be seen, I'm not sure if that's necessary tbh.   So long as a standard mortar will handle the heat and not fall out after a few weeks, then we're good with that; although still not sure what mix to use, what sand, whether to use plasticiser, etc.  

 

Thanks for the post   

[topchippyles]

1 minute ago, carbs for arbs said:

 

Funnily enough, I was reading an article earlier which said exactly this.  Made so much sense and seemed obvious once I'd read it, but I'd never thought of it like that...  I guess there is sacrificial and sacrificial though, and in the case of pointing it is quite a long terms sacrifice!  We're not actually pointing though, just filling a few gaps, and the main reason - which may or may not seem daft - is to stop the heat going into the gaps (would prefer it to come into the room!).

 

 

Thanks   Yes, they're on our radar for several potential jobs, like when we do the full repointing, and also if we have to lime externally once the concrete render comes off.  But because this is such a small job, and won't be seen, I'm not sure if that's necessary tbh.   So long as a standard mortar will handle the heat and not fall out after a few weeks, then we're good with that; although still not sure what mix to use, what sand, whether to use plasticiser, etc.  

 

Thanks for the post   

Really good setup down there and very helpful.

[carbs for arbs]

Quick reply to say we found a bit of an unlikely solution for darkening / staining the hearth....   Coffee!  We used it on some of the lighter bits of mortar too and are really pleased with how it's come out.  Free, no chemicals, and a couple of days buzzing my tits off from the extra caffeine